WO2007053478A2 - Ensemble d'antenne optique - Google Patents

Ensemble d'antenne optique Download PDF

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Publication number
WO2007053478A2
WO2007053478A2 PCT/US2006/042123 US2006042123W WO2007053478A2 WO 2007053478 A2 WO2007053478 A2 WO 2007053478A2 US 2006042123 W US2006042123 W US 2006042123W WO 2007053478 A2 WO2007053478 A2 WO 2007053478A2
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WO
WIPO (PCT)
Prior art keywords
optical antenna
antenna elements
optical
antenna assembly
assembly
Prior art date
Application number
PCT/US2006/042123
Other languages
English (en)
Other versions
WO2007053478A3 (fr
Inventor
W. Daniel Hillis
Nathan P. Myhrvold
Clarence T. Tegreene
Lowell L. Wood Jr.
Original Assignee
Searete Llc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from US11/263,539 external-priority patent/US7957648B2/en
Priority claimed from US11/263,554 external-priority patent/US20070210956A1/en
Priority claimed from US11/263,540 external-priority patent/US20060239686A1/en
Priority claimed from US11/263,656 external-priority patent/US7489870B2/en
Application filed by Searete Llc filed Critical Searete Llc
Publication of WO2007053478A2 publication Critical patent/WO2007053478A2/fr
Publication of WO2007053478A3 publication Critical patent/WO2007053478A3/fr

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Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q3/00—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system
    • H01Q3/26—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system varying the relative phase or relative amplitude of energisation between two or more active radiating elements; varying the distribution of energy across a radiating aperture
    • H01Q3/2676—Optically controlled phased array
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q23/00—Antennas with active circuits or circuit elements integrated within them or attached to them

Definitions

  • the present application relates, in general, to antennas and related components and systems, at or near, optical frequencies.
  • FIG. 1 is a schematic diagram of one embodiment of an optical antenna assembly that is configured to receive optical energy
  • FIG. 2 is a schematic diagram of another embodiment of an optical antenna assembly that is configured to emit light
  • FIG. 3 is a generalized cross sectional diagram of a portion of one embodiment of an optical antenna assembly
  • FIG. 4 is a perspective view of a portion of another embodiment of an optical antenna assembly
  • FIG. 5a is an isometric representation of a portion of another embodiment of an optical antenna assembly that is produced with nanotubes
  • FIG. 5b is a top view of one of the optical antenna elements of the optical, antenna assembly that is shown in FIG. 5 a;
  • " " ⁇ FIG. 6 is a Yiew of one embodiment of an interference pattern created by a plurality of optical antenna elements;
  • FIG. 7 is a view of another embodiment of an interference pattern created by the plurality of optical antenna elements of FIG. 6, in which that relative phase of one of the optical antenna elements is shifted;
  • FIG. 8 is a side view of one embodiment of the optical antenna element and an associated detector, in which the detector is configured as a diode;
  • FIG. 9 is a side view of- another embodiment of the optical antenna element and an associated detector, in which the detector is configured as a transistor;
  • FIG. 10 is a side view of yet another embodiment of the optical antenna element and an associated detector, in which the detector is configured as a Scliottky diode;
  • FIG. 11 is a general schematic view of one embodiment of an oscillator circuit that can be used to produce a signal
  • FIG. 12 is a schematic-diagram of feedback element
  • FIG. 13 is a diagrammatic representation of a portion of an optical antenna assembly having separate optical antenna elements positioned to receive a reference signal
  • FIG. 14 is a- schematic diagram of one embodiment of an array of receiving optical antenna elements
  • FIG. 15 is a schematic diagram of one embodiment of an array of generating optical antenna elements
  • FIG. 16 is a schematic diagram of another embodiment of optical antenna elements, including a reference planar waveform generator
  • FIG. 17 is a top view of one embodiment of an optical antenna assembly;
  • FIG. 17 is a top view of another embodiment of an optical antenna assembly;
  • FIG. 18 is a top view of yet another embodiment of an optical antenna assembly
  • FIG. 20 is a schematic diagram of one embodiment of an optical antenna controller
  • FIG. 21 is a view of one embodiment of an illumination system
  • FIG. 22 is a diagrammatic representation of one embodiment of optical antenna element arrangements.
  • FIG. 23 is a schematic diagram of one embodiment of an arrangement of optical antenna elements according to grid.
  • the optical antenna assembly may include an array of the optical antenna elements.
  • Such arrays of optical antenna elements may, in certain embodiments, be spatially arranged in either a non-uniform or uniform pattern to provide the desired optical antenna assembly characteristics and/or generate or receive light having a desired response.
  • the configuration of the arrays of optical antenna elements within the optical antenna assembly may affect the shape, strength, operation, and characteristics of the waveform received by, or generated by, the optical antenna assembly.
  • Optical antenna elements may be configured to either generate or receive light.
  • the physical structure of a generating optical antenna element can be identical to that of a receiving optical antenna element.
  • a single optical antenna element, or an array of such elements can be used to generate and/or receive light.
  • This disclosure thereby includes a description of the structure or the associated characteristics of a number of embodiments of generating and receiving optical antenna assemblies.
  • the receiving optical antenna assembly as described with respect to FIG. I 3 acts to convert received light (of the visible ' or near-visible spectrarn) into an electrical signal.
  • the generating optical antenna element as described with respect to FIG. 2, converts an electrical signal into corresponding generated light.
  • optical antenna indicates that the antenna generates or receives energy, or otherwise interacts with energy, at or near optical frequencies. This light and/or energy can be converted to/from electrical signals that can be transported along conductive- or similar pathways. The fundamental physics of such optical antenna elements can therefore rely upon the conversion of energy between electromagnetic waves that travel through a medium such as • air or a vacuum, and electrical signals that travel along an electrically conductive or similar pathway, and/or vice versa.
  • a number of publications that relate to nanostructures are described in the publication: "NANO- OPTICS Publications 1997 - 2005"; printed on December 22, 2004; pp. 1-7; Nanooptics Publications; located at: http://nanooptics.uni- graz. at/ol/ol jDublihtml.
  • optical antenna assemblies include, but are not limited to, cameras, telescopes, beamfo ⁇ ners, solar cells, detectors, projectors, and light sources.
  • the terms “visible” or “optical” light, or simply “light” also relate in this disclosure to so-called “near-visible” light such as ⁇ that in ' the near infrared, infra-red, far infrared and the near and far iiltra- ⁇ violet spectrams.
  • near-visible light such as ⁇ that in ' the near infrared, infra-red, far infrared and the near and far iiltra- ⁇ violet spectrams.
  • many principles herein may be extended to m ⁇ my spectra of electromagnetic radiation where the processing, electronic components, or other factors do not preclude operation at such, frequencies;, including frequencies that may be outside ranges typically -considered to be optical frequencies.
  • the term "regular”, when referring to a plurality or array of optical antenna elements, is not limited to substantially evenly spacing between or among various components. Moreover, regular spacing may be satisfied at the points of attachment, or other locations of components, that may not extend in parallel. Further 5 the dimensions of individual components may be small in many embodiments, and minor deviations from exact placement or separation may still be considered regular. Further, regular may -pertain to spacings, features, separations, or other aspects of individual or groups of components.
  • the term "uniform" does not require exact uniformity of size, features, spacing, distribution or other aspects that may be considered to be uniform. Altering a configuration of optical antenna elements by reducing the probability of optical antenna elements forming thereat, forming shorter optical antenna elements in a particular region, removing optical antenna elements from a particular region, etc. can have the effect of altering the optical characteristics of the of the optical antenna assembly.
  • the effective lengths of the • optical antenna elements usually equal some integer multiple of quarter wavelengths of the generated or received light ( ⁇ /4).
  • the physical length, dimension of single wavelength versions of the optical antenna elements can approximately equal the effective wavelength of the generated or received light. Due to the minute wavelength of many of the relevant ranges of light, many embodiments of the optical antenna elements can be fabricated to be minute (e.g. such as within or nano-scale), and still allowing the antenna elements to couple with the electromagnetic radiation that occurs at similar light wavelengths such as within the visible spectrum.
  • optical antenna assemblies can " be designed to provide a variety of efficiencies based largely on coherency of light produced by multiple included optical antenna elements and their coherencies.
  • Light from multiple coherently generating or receiving optical antenna elements may be in phase at a number of locations or at various angular ranges. In such configurations, their wave amplitude may add or interfere coherently at one or more-locations or angles relative to the array of optical antenna element.
  • an optical antenna assembly may be desirable to configure to generate light that is out of phase at one or more spatial locations or angular ranges relative to the optical antenna assembly, and therefore generate or receive substantially incoherent light or partially coherent light at some or all spatial locations or angular ranges relative to the array.
  • the relationship between two adjacent optical antenna elements such, as exists in an antenna array is described herein to indicate how the light from arrays of optical antenna elements constructively or destructively interfere.
  • This constructive and destructive interference is often relevant to such optical antenna assembly issues as wave phases, beamfo ⁇ ning, and bearnsteering as described in this disclosure.
  • The' relationship between the two adjacent optical antenna elements can be extended in principle to either uniform or non-uniform arrays depending upon the desired waveform.
  • While such principles can be relevant to the operation, understanding, and/or characteristics of many embodiments;, a variety of other design principles may be employed in such designs or analyses.
  • antenna elements can destructively interfere at a number of locations relative to the optical antenna elements, and light can constructively interfere at other spatial locations.
  • the . respective generating or receiving optical antenna elements can generate or receive light from one or more spatial locations or angular ranges.
  • the relative phase relationships of the light that is generated or received by the optical antenna element largely dictates those spatial locations, relative to the array, where the combined optical signal is mostly in phase and therefore the amplitude of the combined signals from the array of optical antenna elements contribute to be of the
  • Destructive interference between proximate parrs of optical antenna elements can produce a reduced amplitude or gain in corresponding regions.
  • Adjusting the relative phases of the generating or receiving optical antenna elements can control gain along respective paths relative to the optical antenna assembly at which the light is generated or received.
  • the phases may be controlled to produce a relatively high gain along a limited range of directions. •
  • this process may be referred to as "beamfomiing”.
  • An associated process involves changing the direction of gain. This process may be referred to as "beam steering”.
  • Many embodiments of the optical antenna assembly can be phased array optical devices that utilize beamfomiing and/or beadgingering techniques. In many embodiments, an optical antenna assembly 100 as described with respect to both FIGS.
  • optical antenna elements 102 includes a number of the optical antenna elements 102 that can be arranged in a substantially planar array to form the optical antenna assembly 100, though the structures methods and systems described herein are not limited to embodiments having planar or substantially planar arrangements.
  • the arrangement of optical antenna elements 102 can be either regular or non-regular and can be two- dimensional, or three-dimensional In one approach, a three dimensional arrangement may be achieved by stacking two or more two-dimensional arrays.
  • the arrangements of antenna elements and the configuration of individual optical antenna elements may be varied according to the principles described herein to produce a variety of frequency responses, beam patterns, or other operational properties.
  • This portion of the disclosure describes a number of embodiments of a receiving optical antenna assembly as described with respect to FIG. 1.
  • a subsequent portion of the disclosure describes a number of embodiments of a generating optical antenna assembly, as described with respect to FIG. 2.
  • Several embodiments of optical antenna assemblies, including embodiments according to FIGs. 1 and 2 can be arranged in either a receiving or generating configuration, as described with respect to FIGs. 1, 2, 3, 4, 5a, or 5b.
  • the relevance of having the arrays of optical antenna elements unifomily or non-uniformly spaced within the optical antenna assemblies is described in this disclosure.
  • Certain embodiments of the detector and light source configurations, by which light transitions to, or is transitioned from, electrical signals are also described herein.
  • Tlie optica] antenna assembly 1 C)O that is configured as a receiver can be applied to a number of different applications including, but not limited to, a light detector, a light sensor, a camera, etc.
  • the optical antenna assembly 100 that is configured as a receiver includes a plurality of optical antenna elements 102 that can be each individually coupled to a respective phase adjust (" ⁇ -adjust") 104 via a respective guiding structure, represented as an individual electrical conductor 105. Electrical signals can transit along the guiding structure from the ⁇ - adjust 104 to a combiner 106.
  • materials that may be characterized as dielectrics or conductors at one frequency may operate very differently at other frequencies.
  • the actual material that carries or guides electrical signals or waves will depend upon a variety of factors, including the frequency of the energy propagating. Nevertheless, for clarity of the presentation for the current portion of this description, the various guiding structures are represented diagrammatically and referred to herein as the electrical conductor 105, though the term conductor should not be considered to be limited to materials typically considered to be electrical conductors at relatively low frequencies.
  • the ⁇ -adjust 104 for each light-receiving optical antenna element 102 is capable of adjusting the relative phase of the electrical signal relative to light that is received as a signal formed by each particular optical antenna element 102 at the combiner 106.
  • the ⁇ -adjusts 104 are presented diagrammatically in Figs. 1 and 2 for clarity of presentation.
  • One skilled in the art will recognize that a variety of structures may be implement the ⁇ - adjust 104 functionality, including, in a relatively straightforward implementation, waveguides having materials with fixed or electrically controllable effective dielectric constants and/or optical transmission distances.
  • Other various exemplary embodiments of the ⁇ -adjust 104 will be described in more detail hereinbelow.
  • the ⁇ -adjust 104 controls the effective time required for a signal to travel from the particular optical antenna element 102 to the combiner 106, and therefore the relative phase of a signal carried by the electrical conductor 105.
  • the relative phases of the signals that can be applied from the optical .antenna elements 102 to the combiner canbe adjusted.
  • signals output from each ⁇ -adjust 104 arrive at the combiner 106 for each receiving optical antenna assembly 100.
  • One ⁇ - adjust 104 is associated with eacli light-receiving optical antenna element 102, and the ⁇ -adjust 104 is configured to adjust the relative phase of light being produced or received by functioning as a fixed or variable delay element.
  • each ⁇ -adjust 104 can be configured as a signal-delay component that delays the duration required for a signal to pass through the ⁇ -adjust 104 by some percentage of a wavelength of the light that is to be received or ' generated by other corresponding optical antenna elements 102, thereby alternating the relative phases of the signals produced by the different optical antenna elements.
  • the embodiments of the receiving optical antenna assembly 100 as described with respect to FIG. 1 include the combiner 106 that mixes or otherwise combines signals from the different optical antenna elements, to provide an output signal (not shown) corresponding to the amount of light energy received at the respective optical wavelength of each optical antenna element 102.
  • the combiner 106 is presented diagrammatically as an operational block coupled to the ⁇ -adjusts 104, one skilled in the art will recognize that a variety of configurations may achieve the functionality realized by the combiner. Some such configurations may even employ free- space optical or E-F (radio frequency) techniques to produce a signal that is a function of the signals from the ⁇ -adjusts 104. In some configurations, the signal may be a combination of the signals from the ⁇ -adjusts 104 or may be a nonlinear, square law or other function of such signals, such as a down converted, square law combination,, phase or frequency modulated version, or even an integrated sum of such signals.
  • E-F radio frequency
  • the combiner 106 can be configured to include an adder circuit, a multiplier circuit, a mixer circuit, or some other arithmetic configuration depending upon the functionality of the optical antenna assembly 100.
  • the combiner can also include a signal amplifier that - • amplifies the signal strength that is applied to the combiner 106 to a level (e.g., for certain prescribed frequencies) that is sufficient to transmit the signal to another device, or to an image processor that may identify information represented by the various signals.
  • the combiner 106 can be associated with, or integrated into, a computer device such as a signal processing portion of an analog or digital computer.
  • the computer device functions as a signal processor to analyze, evaluate, store, or otherwise process signals corresponding to the light received from the different optical antenna elements 102.
  • a computer device can be integrated with the combiner 106, and in certain embodiments the computer device can be configured as a full-sized general purpose computer such as a personal computer (PC), a laptop, or a networked computing device.
  • the computer device that is included as portion of the combiner 106 can be configured as a microprocessor, a microcomputer, an application-specific integrated circuit (ASIC), a devoted analog or digital circuit, or other such device.
  • ASIC application-specific integrated circuit
  • the computer device can therefore be configured as a general-purpose computer, a special-purpose computer, or any other type of computer that is configured to deal with the specific task at hand.
  • the combiner 106 includes a multiplexer and/or a downconverter that combines one or more aspects of signals from a plurality of optical .antenna elements 102 or a plurality of sets , of optical antenna elements 102. " While the combiner 106 downconverter is presented diagrammatically herein, a number of structures or materials can operate as combiners;, multiplexers, or downconverters, typically ihiOiigh a nonlinear or linear mixing of signals.
  • Examples of signal downconverters thai operate at or near optical frequencies are described by: J. Ward, E. Schlecht, G. Chattopadhhyay, ⁇ . Maestrini, J. GiIl 3 F. Marwald, H. Javadi, and I. Melidi; "Capability of THz sources based on Scliottky diode frequency multiplier chains"; 2004 IEEE MTT-S Digest; January, 2004; pp. 1587-1590 J. Ward, G. Chattoppadhyay, A. Maestrini, E. Schlecht; J. Gill, H. Javadi, D. Pukala; F. Maiwald; I. Mehdi; "Tunable AH-Solid-State Local Oscillators to 1900 GHz”; December 22, 2004, each of which is incorporated herein by reference.
  • the one or more aspects of the signals can be characterized by a plurality of frequency ranges, a plurality of time samples, or a plurality of other separable or distinguishable features for the signals that originate from pluralities of optical antenna elements into a single signal that can be transmitted to a remote location for processing, or alternatively the processing can be performed in situ.
  • the output from the combiner 106 can " be transferred to a remote location, such as would occur if the optical antenna assembly 100 is configured as part of a network, in certain embodiments of the optical antenna assembly, a variety of components can be operably coupled downstream or upstream of the combiner 106 to assist in the handling or transmission of data signals produced by the combiner.
  • a downconverter includes an optical down- converter that, like other forms of downconverters, decreases the frequency of signals.
  • an optical downconverter is an optical device that mixes the signal to be downconverted with a second optical signal, as may be generated by an associated oscillator 107. Mixing of optical signals to produce a lower frequency indicator of information carried by one or more signals is known.
  • An example of such mixing in polymer based materials is described in Yacoubian, et al, E-O Polymer Based Integrated Optical Acoustic Spectrum Analyzer, IEEE Journal of Selected Topics in Quantum Electronics, Vol. 6, No. 5 September/October 2000
  • the down-converter may be interposed between the optical antenna elements 102 and the ⁇ -adjusts 104, may be interposed between the ⁇ -adjusts 104 and the combiner 106, or may itself include the ⁇ -adjusts 104.
  • the down-converter can be operably coupled to the combiner, wherein the frequency of the electromagnetic radiation that is applied to the combiner 106 is reduced to a level that can be propagated along electrical conductor.
  • a mixer may be applied downstream of the combiner 106.
  • a wavefront 120 indicates a generally planar orientation of light waves arriving at, and/or received by, the respective receiving, optical antenna assembly 100. While the incoming wave in this description is presented as planar for clarity of presentation, the embodiments herein may be configured for operation with a variety of input wave formats, including non-colierent waves and non-planar waves. Moreover, in the disclosure, the term "planar" as applied to . waveforms is not limited to the strictest definitions of planar and may include any substantially planar surface, including those that do not have infinite radii of curvature or those that may, for example,, have slight surface irregularities. For the receiving optical antenna assembly 100, the wavefront 120 is illustrated as moving in a downward direction as indicated by the arrow 124.
  • the receiving optical antenna assembly 100 converts the light energy of the wavefront 120 to electrical energy that travels along an electrically conductive path or other signal transmissive path.
  • the receiving optical antenna assembly 100 can fhereby be considered as an optical transducer that converts received light energy into a different form.
  • the sensitivity, directionality, gain, or other aspects of the optical antenna assembly 100 can be controllably varied, hi certain generating embodiments, this can provide a beainforming and/or beamsteering function.
  • the ⁇ -adjusts 104 may also be configured to selectively block or diminish signals from their respective optical antenna element, as will be described below. Therefore, in certain embodiments, the ⁇ -adjusts 104 can functionally alter the light-generating or light-receiving effects of a particular optical antenna element 102. Removing (or decoupling) certain optical antenna elements from certain arrays of optical antenna elements can make an otherwise regularly-spaced array more non- regulaiiy spaced or more sparse. Alternatively, removing selected, elements can functionally control the gain of the optical antenna assembly along selected paths, vary the width of the center lobe and/or the side lobes, or alter some other characteristics that may be dependent upon frequency. Design considerations relating to the number, position, spacing, and other aspects of the optical antenna elements will be described hereinbelow.
  • each of the optical antenna elements 102 can be configured to receive signals that vary in amplitude or phase at different spatial directions across the array. Examples include, but are not limited to, a telescope, a camera, an image detector, a receiving portion of a facsimile machine, a communications receiver, an image copier, or the like.
  • receiving optical antenna assembly can be arranged to receive a substantially uniform image across the entire face of the display.
  • examples of these embodiments include, but are not limited to, motion detectors, presence detectors, time of day detectors, timing detectors associated with sports- events, or the like.
  • the particular configuration of the various ' components, such as the combiner, can be designed to take into account the type of waveform images that can be received by the optical antenna assembly 100, as well as the uniformity of the waveform image.
  • any configuration of such optical antenna assemblies that produces an electrical signal responsive to received light may be within the intended scope of the receiving optical antenna assembly.
  • FIG. 2 shows a schematic diagram of one embodiment of a generating optical antenna assembly 100 that is configured to emit either coherent light energy or incoherent right energy.
  • a generating optical antenna assembly 100 that is configured to emit either coherent light energy or incoherent right energy.
  • Many of the components and techniques that are .described in this disclosure with respect to receiving optical antenna assemblies also apply to the generating optical antenna assemblies, and vice versa.
  • Different embodiments of the generating optical antenna assembly 100 can be used in a variety of applications that include, bat are not limited to a light source, a display, and/or a variety of other applications that involve directing light toward spatial-locations relative to that array.
  • the receiving and generating embodiments of trie optical antenna assembly 100 can be provided with many identical reference characters since many of the components of both configurations may be identical or similar, and in some cases, both configurations may actually be used interchangeably.
  • certain components of the generating optical antenna assembly may be configured differently for the remaining optical antenna assembly (e.g., such as having differing circuitry and/or different biasing) to provide for different operational characteristics.
  • the optical antenna assembly 100 may be configured to generate coherent radiation at certain locations similarly to laser or holographic devices, other embodiments of the optical antenna assembly may produce incoherent light. Such a light source could be steerable and controllable to produce coherent or incoherent light at different tirnes and or different spatial locations or along selected paths.
  • the plurality of optical antenna elements 102 included within the generating optical antenna assembly 100 can be arranged in an array.
  • the optical antenna assembly 100 may. include one, or a number of, discrete optical antenna elements 102. Each optical antenna element 102 can be individually attached or operably coupled via a distinct ⁇ -adjust 104. The embodiment of the generating optical antenna assembly 100, as described with respect to FIG.
  • the signal splitter 205 includes the one or more optical antenna elements 102, corresponding ⁇ -adjusts 104, the electrical conductors 105, and signal splitter 205.
  • the signal splitter 205 diagrarnmatically represents a component or set of components that distribute signals among the various optical antenna elements 102.
  • the signal splitter 205 may actually includes functions such as signal combining in some embodiments.
  • the signal splitter 205 may combine selected signals with signals from an associated oscillator 206.
  • the signal splitter 205 outputs an electrical signal that is a combination of an information signal and the signal from the oscillator. 206.
  • the ⁇ -adjust 104 produces a phase adjusted, version of the signal to drive the respective optical antenna element 102.
  • the output of the optical antenna element 102 thus corresponds to the information signal and the oscillator signal.
  • a varying, or consistent, level of iHumination can be created across all of the optical antenna elements 102 within the optical antenna assembly 100.
  • each of the optical antenna elements 102 may generate relatively broadband light at its respective spatial location.
  • the optical antenna elements 102 may be matched to selectively produce light in one or more narrow bands or one or more substantially discrete frequencies. Where the light is in one or more narrow bands, the optical antenna elements 102 may be sufficiently matched to generate coherent light energy.
  • the intensity of the signal from each of the optical antenna elements 102 may be controlled on an individual element basis or according to groupings of elements to provide controllable illumination at respective spatial locations. Where the pattern of the illumination matches a selected image, the emitted light energy may produce a viewable display.
  • the optical antenna elements 102 may be configured to emit light at one or more visible wavelengths so that viewable image may be directly viewable or viewable on an image surface, such as a screen or diffuser.
  • the emitted light may be at frequencies not directly viewable by humans and converted to visible light through wavelength conversion, hi one simple approach to wavelength conversion, the emitted light strikes a phosphor, which may be upconverting or downconverting depending upon the configuration, and the phosphor emits visible light with an energy level corcespondiiig to the to level of the emitted non-visible light.
  • the gain may be controlled as described herein to directionally control beam gain, to produce a scanning beam display.
  • the ⁇ -adjusts 104 effectively adjust the relative transit time for a signal (in either direction) between the respective optical antenna element ] 02 and the corresponding signal splitter 205.
  • the ⁇ -adjust 104 can thereby alter the relative phase of the light that is generated by the respective generating optical antenna elements.
  • phase control may allow the generating optical antenna assembly 100 to act as a beamsteerer and/or beamformer to control the directionality or angular gain relative to the array of optical antenna elements 102.
  • the oscillator 206 In the embodiment of the optical antenna assembly 100 as described with respect to FIG. 2 5 the oscillator 206 generates an electrical or optical signal that can be supplied to the respective optical antenna element 102, If the signal that is generated from the oscillator 206 is an electrical signal, the signal may directly drive the optical antenna element 102 or the frequency may be lower than that to be emitted by the optical antenna element 102. In such configurations, an Tip-converter, as will be described below, can convert the frequency of the electrical signal into the frequency of the light from each optical antenna element. Signals output from each, oscillator 206 can therefore be applied to one or more respective ⁇ -adjusts 104 that are associated with each generating optical antenna assembly 100. Each ⁇ - adjust 104 may then adjust the relative phase of the light to be generated by each respective optical antenna element 102. As such, each ⁇ -adjust 104 acts as a variable delay element for signals applied to the optical antenna element 102.
  • the signal splitter 205 is shown in FIG. 2 as being associated with the oscillator 206.
  • Some embodiments of the optical antenna assembly 100 use an oscillator 206 to generate a signal, that may he sinusoidal, of a particular frequency that may then form a reference or earner signal.
  • the oscillator 206 can be configured in a number of different embodiments, as described below with respect to FIGS. 11 , 12, and 13. It is emphasized that the different embodiments of the oscillator as described in this disclosure are illustrative in nature, and are not intended to be limiting in scope. As such., other embodiments of oscillators can be considered to be within the intended scope of the present disclosure.
  • a single oscillator 206 can generate a signal, which may be sinusoidal, that can he applied to individual, multiple, or all of the optical antenna elements 102 within the optical antenna assembly 100.
  • each of the array of display picture elements (pixels) may be defined by one or more optical antenna elements 102, such that each of (or each group of) the optical antenna elements 102 is associated with a distinct oscillator 206. If substantially uniform levels of illumination are to be provided across multiple optical antenna elements, then fewer oscillators 206 that each supply a consistent signal to multiple optical antenna elements may be used.
  • the signal combiner 205 can be configured with one oscillator circuit which applies an identical input signal to each of the generating optical antenna elements 102.
  • the signal splitter. 205 is . functionally configured to split an input signal, such as the information signal into two or more output signals that may be identical.
  • Each of the output signals drive a respective generating optical antenna element 102 or may form a carrier signal that may be combined with another signal (such as a signal from the oscillator 206) to drive the respective optical antenna element 102.
  • Such an embodiment may still employ ⁇ -adjusts 104.
  • each ⁇ -adjust 104 adjusts the time for the oscillator's signal to reach the corresponding optical antenna element 102, and therefore the relative phase of that optical antenna element.
  • the ⁇ -adjusts 104 in the generating configuration of their respective optical antenna elements 102 and thereby alter the phase of the light generated across the array of elements within the optical antenna assembly 100.
  • phase control can employ known techniques ,to control the effective direction of , emitted energy for localized or directional illumination.
  • Certain embodiments of the generating optical antenna assembly 100 may include an up-converter that is associated with the signal splitter 205.
  • the up-converter acts to transition light to the frequency of a received electrical signal, such as may be modulated according to information content into a signal at optical frequencies.
  • Such an up-converter is typically a nonlinear, square law or similar device that produces an output that is a function of the information bearing signal and a second signal, such as may be provided by the oscillator 206.
  • An example of a non-active form of up- converter can be found in T. J. Yen, WJ. Padilla. N. Fang, D. C. Vi er, D. R. Smith, J.B. Peiidry, D.N. Basov, X. Zhang; "Terahertz Magnetic Response from Artificial Materials”; Science Magazine Reports; March.5, 2004; pp. 1494-1496; Volume 303; which is incorporated herein by reference. .. .
  • generating optical antenna assembly 100 include an oscillator that generates signals at optical frequencies directly, thereby bypassing the need for a separate up-converter. It is also envisioned in certain embodiments that a mixer circuit, multiplier, nonlinear circuit, or other suitable frequency conversion configuration, can up-co ⁇ vert or downconvert the frequency of the electrical signal that is to be transmitted or received by the signal combiner 205 from optical frequencies to frequencies that may be handled more easily by conventional circuitry.
  • An example of a device that generates harmonics of an input signal is described in the article: S. Takahashi, A. V. Zayats; "Near-field second ⁇ harmonic generation at a metal tip apex"; Applied Physics Letters; May 13, 2002; pp. 3479-3481; Volume 80, Number 19; American Institute of Physics, incorporated herein by reference.
  • any configuration of optical antenna assembly that generates light in response to a- received electrical signal may be within the intended scope of the generating optical antenna assembly.
  • each receiving or generating optical antenna element 102 is configured to respectively receive light or .generate light within the visible as well is near-visible light- spectrum.
  • visible wavelengths are on the order of 400-700nni.
  • near visible wavelengths can be considered to be from about 300nm up to about l,900ni ⁇ i.
  • other optical ranges may be applicable.
  • the principles and structures described herein may be extended in some cases to substantially shorter wavelengths, such as those of known photolithographic techniques.
  • Such wavelengths can be currently on the order of a few tens of nanometers, e.g., 40Hm 5 although future production techniques can be expected to reduce these to the single nanometer ranges, or even smaller.
  • the principles herein should be adaptable to such dimensions, taking nanoscale effects into account.
  • the upper wavelength (lower frequency) limits are not necessarily limited to visible or near visible wavelengths.
  • the principles, structures, and methods herein may be applicable at wavelengths in the near infrared (e.g., about 700-5000 nm), mid-infrared (e.g., about 5000nm-25 micron), or far infrared (e.g., about 25-350 micron ranges).
  • the upper end of the inid.-ir ⁇ fra.red range is sometimes defined as about 30 or 40 microns and the upper end of the far infrared is sometimes defined as about
  • a quarter-wave optical antenna element 102 has an effective length substantially equal to one-quarter the wavelength of the received/generated light for the corresponding medium.
  • a half-wave optical antenna element 102 has an effective length substantially equal to one-half the wavelength of the received/generated light, for the corresponding medium!
  • the wavelength depends upon the configuration and associated media, including the effective dielectric constant of the media through which the signals propagate. . . . .
  • the individual optical antenna elements 102 can be arranged in arrays to form the optical antenna assemblies, and hence the optical antenna elements may be fabricated within the nano- or micro-scale. It is therefore envisioned that many optical antenna assembly applications will involve a large number of the optical antenna elements that can be arranged in an array. As such, one fabrication approach employs semiconductor processing techniques to produce a number of elements having well controlled positioning and/or dimensions.
  • Such fabrication approaches may be selected in cases where there are little operation and configuration variations between the individual optical antenna elements, though other systems may also employ such techniques.
  • Appropriate semiconductor processing techniques include, but are not limited to, lithography (such as photo-lithography, e-beam lithography), nanot ⁇ be growth, self assembly, or fabrication of other nano structures.
  • lithography such as photo-lithography, e-beam lithography
  • Other known techniques that can be used to produce large arrays of optical antenna elements can be within the intended scope of the present disclosure.
  • the different embodiments of the optical antenna assembly 100 can therefore be considered as an optical antenna that "captures” or “generates” light energy, as described respectively with respect to FIGS. 1 and 2.
  • phase control of the individual optical antenna elements may allow the gain of the optical antenna assembly to be defined independently of conventional optical focusing or processing techniques, such as with lenses, or of diffractive, refractive, or reflective elements, including left handed materials.
  • the principles, structures, and methods described herein do not necessarily exclude use with more conventional optical focusing, shaping, processing or other techniques, such as lenses, diffractive elements, phase plates, filters, apertures, polarizers
  • optical antenna assembly 100 Typical analysis of photon emitters or receivers traditionally has been considered under the domain of quantum physics, as often characterized by Schroedinger's equations. While such analysis may be applic ⁇ ible to many aspects of the devices and systems described herein, the design and characteristics of the optical antenna assembly 100 will typically involve more Maxwellian analysis and design. As such, many of the antenna techniques and equations that apply to antenna design, wave propagation, coupling, and other aspects of the microwave, and other, electromagnetic radiation spectra may be applied relatively directly to the designs and systems described herein. For example, optical antenna assembly designs, concepts and analysis may use phased-array techniques for synthetic apertures or other antenna-related concepts to detect, generate, direct, or otherwise interact with energy at optical frequencies.
  • FIG. 3 shows diagrammatically a side view of one generalized embodiment of the optical antenna assembly 100 as described with respect to FIGS. 1 and/or 2.
  • the optical antenna assembly 100 can be fabricated using a variety of semiconductor processing techniques or other suitable techniques.
  • the substrate 202 or supporting body carries such elements as the ⁇ -adjust 104, the combiner 106, the signal spUtter 205, or the oscillator 206 as described in either FIG. 1 or FIG. 2, though these are omitted from FIG. 3 for directness of presentation.
  • the term "carries" in the physical, rather than signal carrying, context may apply to a component, such as the optical antenna element, being individually attached or operably coupled to the substrate 202, integrated into or contained within the substrate, operably coupled to some intermediate structure that attaches the optical antenna element to the substrate, or any other type of arrangement where the substrate can be said to carry or support.
  • the substrate 202 can be configured considerably differently than conventional semiconductor substrates. For example, materials such as polymers, metals, rubber, glasses, or minerals can form the substrate that carries the optica] antenna elements.
  • some type of field can be established to maintain the optical antenna element in position with respect to each other in addition to or independent of physical structural support.
  • the substrate may also include additional components in some configurations, such as up-converters, down-converters, mixers, and/or de- mixers that are described with respect to certain of the figures).
  • a row of optical antenna elements 102 may be positioned behind or beside each optical antenna element 102 shown in FIG, 3, thereby creating a two- dimensional array of optical antenna elements 102.
  • the elements 102 can be positioned in a relatively stacked arrangement, multiple substrates, or one or more layers formed on substrates that each contain a two-dimensional array of optical antenna elements can be positioned in fixed or variable positions relative to each other.
  • the two dimensional arrangements can be accomplished by variable spacing between the rows of optical antenna elements 102 or other nonuniform arrangements.
  • Such two dimensional arrangements may be stacked, deposited, formed or otherwise assembled or fabricated with a stacked, layered, or other three dimensional arrangement to form a three-dimensional array of optical antenna elements.
  • Such three-dimensional arrays can- be used for a variety of purposes, for example as a group of cooperating optical antenna elements.
  • one or more of the layers of optical antenna elements may operate as a reference waveform generator.
  • the reference wave may provide a driving signal for down converting or mixing, may operate as a relative phase control, or may provide a reference w 7 ave against which incoming or outgoing waves can be compared.
  • the energy of the reference wave may be applied simultaneously with that of an incoming wave to produce an electrical signal that corresponds to a linear or nonlinear combination of the incoming and reference waves.
  • the electrical signal corresponds to the sum of the amplitudes of the reference wave and the incoming wave. If the two waves are at substantially the same frequency, the sum may be a coherent sum and provide relative phase information.
  • each row and/or column of optical antenna elements 102 is relatively uniform to produce regular arrays of optical antenna elements 102.
  • each one of the optical antenna elements may be irregularly spaced to produce relatively non-uniform arrays of optical antenna elements.
  • a variety of regular or irregular arrays of optical antenna elements can be selected depending upon the desired antenna gain and beam pattern. Where the relative phases of rncorning or outgoing waves can be determined or controlled, the gain or directionality of the optical antenna assembly can be controlled using beamfo ⁇ ning and beamsteering concepts. The design, material, or the configuration of the optical antenna elements may be selected based upon the particular design or application of the array of the optical antenna element.
  • lithographical approaches can produce a large number of different embodiments of arrays of optical antenna elements 102, or discrete optical antenna elements.
  • the complexity of each optical antenna element ranges from relatively simple dipole optical antenna element configurations, including for example, nanotubes or conductive or dielectric pillars, to those including bends, curves, discontinuities, or other irregular configurations.
  • Lithographic techniques can be used to pattern the optical antenna elements or other parts of the optical antenna assembly into a more complex shape to form, for example, curves, angles, or discontinuous structures such as may be used to produce impedance matching structures ; , phase control structures, diodes, transistors, capacitive structures, inductive structures, resistive structures, vias, or other structures, including those that can be more complex or include combinations of such structures.
  • phase control structures, diodes, transistors, capacitive structures, inductive structures, resistive structures, vias, or other structures including those that can be more complex or include combinations of such structures.
  • nanotube-based structures have been developed with integral bends that have been shown to be capable of providing nonlinear electrical responses. Such, structures ma ⁇ ' act simultaneously as optical antenna elements and nonlinear devices. Lithographic techniques can therefore be used to repetitively produce a number of arrays of similar or dissimilar components quickly and accurately.
  • a protective photoresist layer is deposited atop a substrate or other planar object that is formed from a semiconductor material or metal.
  • the photoresist layer is patterned such as is generally known, with a variety of photo-based development processes.
  • An exposed portion of the material is then etched or otherwise removed, for example, through ion beam or e-beam milling.
  • a number of other fabrication techniques may be appropriate. For example, direct e-beam lithography, lift-off techniques, iiano growth or other techniques may be selected, depending upon the particular configuration, application, dimensions, or other factors.
  • FIG. 4 shows an embodiment of an optical antenna assembly 100, in which ring shaped optical antenna elements 102 are formed on the substrate 202 using lithographic techniques, such that the materials may be deposited according to known techniques. Deposition may be appropriate in a variety of configurations, including those where the optical antenna elements 102 can be on the order of some fraction of the wavelength of the incoming or outgoing light.
  • optical antenna elements 102 of FIG. 4 are presented as ring shaped, other geometric or non-geometric shapes may also be selected.
  • each optical antenna element 102 may be formed with metals as gold, silver, aluminum, or copper.
  • the antenna element material may be provided, for example, by electrochemical deposition, physical-vapor deposition, chemical vapor deposition, or may be grown in a variety of manners.
  • the optical antenna elements may also be formed from semiconductor or similar materials such as carbon or silicon based materials that can be typically doped or otherwise combined with additional materials.
  • the metal and/or semiconductor materials of the optical antenna element can be selected to have a relatively high electron mobility. High electron mobility materials have been developed to operate at relatively high frequencies. For example, terahertz band high electron mobility devices have been reported.
  • optical antenna elements Minimum achievable dimensions of features produced by semiconductor or similar fabrication techniques are steadily decreasing.
  • the current level of dimensions can produce many embodiments of the optical antenna elements.
  • integrated circuit manufacturers have released commercial devices with dimensions below lOOrrm and have announced plans for dimensions to a few tens of nanometers. It is expected that the precision, dimensional control, manufacturability and other aspects of the structures and methods described herein may benefit from such technological developments.
  • Such technological developments may be expected to produce optical antenna elements having dimensions on the order of a few tens of nanometers.
  • optical antenna elements can have high vertical aspect ratios, for example 10: 1 or greater
  • a dipole optical antenna element, or a non-regular antenna, of 700 mn, BSOnin, or 175nm is therefore realizable using current technologies.
  • e-beam lithography Another technique that can be used to generate a number of embodiments of optical antenna elements is e-beam lithography.
  • e-beam lithography Another technique that can be used to generate a number of embodiments of optical antenna elements.
  • the user can precisely control the shape and dimensions of a feature that is being produced.
  • Many embodiments of e-beam techniques provide for higher precision than current lithographic techniques, and provide for forniing features having dimensions down to a couple of nanometers.
  • One relatively straight-forward One relatively straight-forward .
  • the technique involves fabricating the optical antenna elements as metal lines on a substantially uniform semiconductor silicon substrate, or alternatively on a complex substrate such as a silicon- ⁇ n-insulator (SOI) substrate, a silicon- on-sapphire substrate, a silicon-on-diamond substrate, or any other suitable configuration of substrate (or other item that is configured to maintain the relative position of the ' optical antenna elements) using conventional semiconductor manufacturing approaches.
  • SOI silicon- ⁇ n-insulator
  • SOI silicon- ⁇ n-insulator
  • silicon- on-sapphire substrate silicon-on-diamond substrate
  • Other materials including semiconductors, dielectrics, or conductors can form the substrate.
  • FIGS. 5a and 5b show one embodiment of the optical antenna assembly 100, including each of a plurality of nanotubes that form the array of optical antenna elements 102 -as carried by the substrate 202.
  • Optical antenna assemblies can include a large number and variety of configurations of optical antenna elements, and can be formed as dipoles, curved structures, discontinuous structures, etc. can be grown using carbon-based nanostructure technology (e.g., using carbon-based or other nanotiibes).
  • a large number of nanotubes can be grown to form an array of optical antenna elements using nano-str ⁇ cture techniques by, for example, having minute depressions initially being formed as a pattern upon a substrate using such techniques as lithography.
  • the locations of the one or more depressions correspond to the desired locations of the nanotubes to be grown.
  • the patterned substrate is then located in a deposition chamber for as long as desired depending upon the length of the nanotubes.
  • the locations of the patterned . depressions can be referred to in this disclosure as "seed regions" since the nanotubes can be selectively grown at the location of the patterned depressions.
  • nanotubes form as thin structures, ranging from one to tens of molecules hi diameter for different embodiments of the nanotubes.
  • each optical antenna element 102 may be grown at the location of a defect in a substrate.
  • the nanotubes can be grown at an angle with respect to the surface (including parallel to the surface).
  • Each optical antenna element can have different, or even random, angular orientation with respect to the surface of the substrate.
  • each nanotube can be fabricated straight, or fabricated as having some curvature. In this disclosure, the curvature can be considered as a non-regular antenna configuration that is differentiated from the regular dipole antenna configuration.
  • the duration of growth and the rate of growth determine the resulting desired height, angle, and curvature of each nanotube.
  • certain nanotubes can be even crossed or crossed and joined to form an intersection point.
  • the nanotube can be allowed to grow for a prescribed time duration corresponding to that length and rate of growth.
  • Such approaches have been applied to produce nonlinear devices such as transistors, diodes, and field emission structures, as described for example in M. Ahlskog, JR. Tarkiainen, L. Roschier, and P. Hakonen.
  • FIG. 5b shows a top view of one embodiment of the nanot ⁇ bes as shown in FIG. 5a.
  • Multiple nanotubes that form an array can be grown to a uniform height, or different heights, as desired.
  • Many embodiments of the nanotubes can be carbon-based, although any suitable material that can be used and is within the intended scope of the present disclosure.
  • the array of the optical antenna elements 102 as described with respect to FIGs. 5a and 5b can therefore be arranged in a one-dirnensional, two-dimensional, or three dimensional nano-stracture pattern, and may be either formed in a regular or an irregular pattern.
  • the embodiments of optical antenna elements 102 that are described with respect to FIGS. 3, 4, and 5a may be used to fabricate either the generating or receiving optical antenna elements 102 within the respective generating or receiving optical antenna assembly 100.
  • a number of the different embodiments.. of .the patterns of optical antenna elements 102 that form an array in the optical antenna assembly 100 are described later in this disclosure.
  • nanot ⁇ be-based optical antenna element fabrication techniques can use crystalline procedures, can use polymers, or even can use biologically inspired polymers (such as deoxyribonucleic acid (DNA) or proteins).
  • the structure of the resulting nanotubes can be crystalline.
  • nanotubes can be conceptually formed as a crystalline structure by forming a planar graph graphene sheet into a cylinder, and capping the ends of the cylinder with a semi-spherical "buckyball".
  • Other configurations of, and processes for, forming nanotubes or similar structures can also be "within the intended scope of the present disclosure.
  • the crystalline approaches might be more suitable to optical antenna elements that can he arranged in a pattern perpendicular to the plane formed by the waveform, either for a generating or receiving optical antenna element.
  • optical antenna assembly designs can leverage existing knowledge of optical systems that operate, for example, in the microwave or millimeter range.
  • optical antenna assemblies could be applied to either broadband or narrowband antenna applications.
  • a number of different configurations of receiving optical antenna assembly configurations can operate as detectors.
  • One embodiment of trie optical antenna assembly simulates human vision by providing three arrays of tuned optical antenna elements, with each one of the three arrays being optimized or tuned for operation at the light frequencies that is particularly detectable by human vision (red, green, and blue wavelengths of light).
  • Each- of the three arrays of optical antenna elements can be formed as -a distinctive ring.
  • three arrays of optical antenna elements 102 form three concentric ring arrays (or other shapes of arrays) that can each be configured/colored as red, green, and blue light-receiving rings (not shown).
  • the receiving optical antenna assembly that detects a plurality of light frequencies corresponding to colors such as red, green, and blue; it is also within the intended scope of the present disclosure to provide multi-colored generating optical antenna assemblies that generate or receive other ranges of multi-colored light.
  • Such multi-colored generating or receiving optical antenna assemblies may be applicable to display and projector applications, such as is likely for next generation television, display, projector, computer, theater, or other similar applications.
  • the multi-color or dual-color receiving or generating optical antenna assemblies may be configured to operate in other visible light ranges, or infrared or ultraviolet ranges.
  • Generating or receiving optical antenna assemblies may be configured to generate/receive light of a variety of distinct frequencies, frequency ranges, or combination of frequencies or frequenc ⁇ ' ranges, while remaining within the scope of the present disclosure.
  • it may be desired to use optical antenna elements that can generate or receive light in the near infrared or near ultraviolet light spectrum, as may be useful for a variety of applications, including thermal imaging, ultraviolet illumination or detection, or any other appropriate application.
  • Such transmission or detection may provide more selectivity, simplified detection, synchronous operation, and/or reduced cost or complexity.
  • the particular light application should be considered when determinhig the frequency of the generated or received optical energy. Examples of Optical Antenna Phase Techniques
  • FIG. 6 displays one embodiment of signals, which may be sinusoidal, being generated by a plurality of optical antenna elements 102a and 102b that together forms an associated signal-strength graph.
  • FIG. 7 displays one embodiment of FIG. 6 in which the highest amplitude generated light is beamsteered upwardly by a few degrees with respect to FIG. 6. WMIe an array of optical antenna elements 102 would typically include a large number of elements; only two optical antenna elements 102a and 102b are illustrated in FIGs, 6 and 7 for clarity in describing certain beamfo ⁇ ning and beamsteering techniques. These concepts can be extended to much larger arrays of optical antenna assemblies 100, Each optical antenna element 102a and 102b radiates signal patterns such as are illustrated in FIGs. 6 and 7 as respective signal lines 702a and 702b.
  • the respective signal lines 702a and 702b generated by the optical antenna elements 102a and 102b are represented in the drawing as being radiated in a generally hemispherical pattern.
  • the actual emission pattern from each of the elements may depend upon the configuration of the individual antenna element and on the materials and/or structures of, surrounding, or near the individual elements.
  • patterns other than hemispherical may be within the scope of this disclosure, though hemispherical is selected for clarity of presentation of the concepts herein.
  • the description of propagation and interaction of waves herein is simplified to a case where the waves are typically of the same wavelength. This aspect lends itself in many cases to coherent wave interaction.
  • variations in frequency, differences in frequency, non-coherent concepts, and other types of interaction and related techniques and principles may be applicable for certain configurations or applications of the methods and structures described herein.
  • each signal line 702a and 702b represents, for example, a crest of a sinusoidal pattern that is formed by respective optical antenna elements 102a and 102b.
  • the location where the signal lines 702a and 702b intersect represents those phase intersection points 704 where the signal lines 702a and 702b correspond to ea ⁇ h other (are both at a crest), and therefore can be in phase.
  • FIGS. 6 and 7 illustrate a number of phase intersection lines 706 that pass through many of the phase intersection points 704.
  • the largest and, typically, the strongest of the phase intersection lines 706a corresponds to a main lobe 708 as shown in the signal strength plot
  • phase intersection lines 706a, 706b, and 706c deterrnine the locations where waves constructively add to form amplitude peaks.
  • Two additional phase intersection lines 706b and 706c correspond to side lobes 710 in the signal strength plot in FIGS. 6 and 7.
  • the signals from both optical antenna elements 102a and 102b add constructively.
  • the phase intersection lines 706a, 706b, and 706c typically correspond to the highest light amplitude regions of the optical antenna assembly.
  • FIGS. 6 and 7 present a simplified presentation of coherent interaction, and demonstrate how formation of the main lobe 708, as well as the side lobes 710, or the general direction of the phase intersection lines 706a, 706b, and 706c follow antenna pattern techniques and concepts, the availability of many elements and the control of element positioning will often permit much more flexibility in relative position, number, orientation, and other characteristics of the antenna assembly. Designs utilizing such flexibility can be developed using conventional analytical or computer based techniques for designing or analyzing arrays of antenna elements.
  • FIGs. 6 and 7 illustrate either generating antenna patterns according to the generating optical antenna elements 102a and 102b, such antenna pattern concepts can be also applicable to receiving optical antenna elements.
  • Antenna patterns, for both the generating and receiving optical antenna elements 102a and 102b, correspond largely to the relative phase and amplitude of the light- waves as indicated by the respective signal lines 702a and 702b.
  • FIG. 7 shows that changing the phases of the respective signal lines 702a and 702b can change the location of the phase intersection lines 706a, 706b, and 706c as well as the characteristics of the main lobe 708 and the side lobes 710 (characterized by the location, relative magnitude, width, or other features).
  • FIG. 7 illustrates the effect of shifting the phase of the wave generated or received by the lower optical antenna elements by some amount with respect to the waves generated/received by the upper optical antenna element.
  • phase of the lower optical antenna element 102b is altered (e.g. steered ahead) with respect to the phase of the upper optical antenna element 102a by 180 degrees.
  • This process of sMftiirg the phase of the signal that is generated by at least one of the optical antenna elements 102 with respect to another of the optical antenna elements to control directionality of the optical antenna assembly is referced to herein as beamsteering for convenience, though the concept of controlling the structure, direction and/or shape of the antenna pattern may be addressed in contexts other than directing a beam of energy.
  • Beamsteer ⁇ ig can also shift the relative positions of the main lobe 708 and the side lobes 710 with respect to the optical antenna elements 102a and 102b. Note, for example, that the main lobe 708 and the side lobes 710 as described with respect to FIG. 7 are rotated in a ; generally counter-clockwise direction when compared to FIG. 6. In a simplistic example, increasing a gradient of the phase difference between waves from different optical antenna elements increases shifting of the main lobes and/or the side lobes. While the concept of beamsteering may become more computationally involved as the number of the optical antenna elements in an array is increased, conventional approaches can still be used.
  • This disclosure provides a number of embodiments of techniques by which beamsteering, beamfo ⁇ ning, antenna pattern control, or other adaptive antenna techniques can be applied to optical antenna assemblies 1-00.
  • Other embodiments of beamsteering and beamforrning techniques across a variety of arrays of optical antenna elements 102 may be within the intended scope of the present disclosure.
  • the optical antenna elements may be fabricated according to photolithographic or similar techniques and may be on the order of a portion of an optical -wavelength or a few optical wavelengths. Consequently, in some configurations an optical antenna assembly may include a large number, several thousand or even millions of antenna elements 102.
  • a 1,000 by 1,000 element array may have a cross-sectional area on the order of lmm by 1mm.
  • Such a small assembly may be useful as a component of a variety of light capturing devices or systems, such as cameras, copiers, scanner, optical detectors, or may be useful in many other light capturing configurations. Additionally, components of such size may be useful in light emissive applications ranging from illumination to coherent beam generation.
  • While compact assemblies may have inter-element spacings on the order of a portion of a wavelength to a few wavelengths, in some applications it may be desirable to have larger inter-element spacings.
  • Such arrangements with increased spacing between the optical antenna elements may he applied to such applications as synthetic aperture radar (SAR) systems, sparse antenna arrays, radio telescopes, or the like.
  • SAR synthetic aperture radar
  • the signals include any propagation, includhig polaritons and phononic.
  • propagation when reference is made to energy traveling or propagating along an electrical path, it is intended that the propagation can include within, adjacent to, outside of, parallel to, through, and any other known conduction mechanism relative to an electrical path.
  • volume 68 Number 15; The American Physical Society; and N. Stoyanov, D. Ward, T. Feurer, K. Nelson; "Terahertz polariton propagation in patterned, materials ' "; Nature Materials-Letters; October 2002; pp. 95-98; Volume 1; Nature Publishing Group, ; and J.P. Kottmarrn, Olivier J.F. Martin; "Plasmon resonant coupling in metallic nanowires"; Optics Express; June 4, 2001; pp. 655-663; Volume 8 5 Number 12 5 each, of which is incorporated herein by reference.
  • Ebbesen "Surface Plasmon Polaritons and Their Role in the Enhanced Transmission of Light through Periodic AiToys of Suhwavelength Holes in a Metal Film”; Physical Review Letters; March 12, 2004; pp. 107401-1/107401-4; Volume 92, Number 10; The American Physical Society; H. Ditlbacher, J.R. Kre ⁇ n. G. Schider, A. Leitner; F. R. Aussenegg; "Two-dimensional optics with surface plasmon polaritons”; Applied Physics Letters; September 2, 2002; pp. 1762-1764; Volume 81, Number 10; American Institute of Physics, H.
  • such analyses may be applied to negative refractive or left-handed materials, as described in R. Rirppin; "Surface polaritons and extinction properties of a left-handed material cylinder”; Journal of Physics: Condensed Matter; August 13, 2004; pp. 5991-5998; Volume 16; IOP Publishing Ltd, and T. J. Yen, WJ. Padilla, N. Fang, D. C. Vier, D. R. Smith, IB. Pendry, D.N. Basov, X. Zhang; "Terahertz Magnetic Response from Artificial Materials”; Reports; March 5, 2004; pp. 1494- • 1496; Volume 303; Science Magazine; each of which is incorporated herein by reference.
  • energy may considered to be propagated adjacent, internal, and/or external to a guiding surface, such as a metal, nanotube, photonic crystal, or other material.
  • the relatively high frequency of the light will impact the analysis and design.
  • Light having a . wavelength of, e.g., 500 run has a frequency of approximately 600Thz, while light having a wavelength of 30 microns has a frequency of about 10 THz and light having a wavelength of 300 microns has a frequency of about 1 . THz.
  • many commercially available components typically used for lower frequency assemblies may not yet be available at optical frequencies.
  • the capacitance, inductance, and other parameters will also scale.
  • operational frequencies of available components rise, the simplicity and manufacturability of such devices is expected to improve. More details regarding operation of certain embodiments of such components are discussed below with reference to mixing.
  • Antenna elements with integrated nonlinear devices can operate as either or both of optical antenna elements 102 and mixers.
  • the electrical energy may be mixed or otherwise compared to a second electrical signal produced in response to a reference optical • signal.
  • a high frequency signal is mixed with a reference signal in a nonlinear device, such as a diode or transistor to produce signals having a frequency corresponding to a difference between the high, frequency signal and the reference signal.
  • the reference signal is generated with a local oscillator, according to techniques such as those described for example in A. Maestrrni, J.. " Ward, J. Gill; G. Chattopadhyay, F. Maiwald, K.
  • hifo ⁇ nation content of the optical signal may be detected synchronously, through optical or electrical approaches.
  • ⁇ an optical reference signal is applied to one or more antenna elements to produce a reference electrical signal.
  • the reference electrical signal and the electrical signal corresponding to the received optical signal can be mixed, in a nonlinear or similar signal processing device, such as a transistor., diode, or bolometer to produce a downconverted signal component that may be processed further.
  • a nonlinear or similar signal processing device such as a transistor., diode, or bolometer to produce a downconverted signal component that may be processed further.
  • the nonlinear device may be integral to or integrated ' with the optical antenna elements 102.
  • the antenna elements 102 convert incoiiring optical energy to electrical energy and the electrical energy is integrated or accumulated over some tune duration.
  • An example of a radiation detector that uses the bolometer effect is described in the article: G.N. Gol'tsman, A.D. Semenov; Y.P. Goixsev; MA. Zorin; IG. Gogidze; E.M. Gershenzon; P.T. Lang; WJ. Kiiott; K.F. Renk; "Sensitive picosecond NbN detector for radiation fi'om millimetre wavelengths to visible light"; Supercond. Sci.
  • the accumulated electrical energy can be detected using conventional electronic techniques.
  • electrical energy can be detected and/or measured using photonic techniques similar to those described in G. Schider, J.R. Krenn, A. Hohenau, H. Ditlbacher, A. Leitner, F.R. Aussenegg, WX. Schaich; I. Puscasu, B. Monacelli, G.. _ Boreman; "Plasnion dispersion relation of Au and Ag nanowires"; Physical Review B; 2003; pp " .
  • volume 68 Number 15; J.R. Krenn; "Nanoparticle Waveguides Watching energy transfer”; News & Views; April 2003; pp. 1-2; Volume 2; Nature Materials; or Nature Materials-Letters; September 2004; pp. 606-609; Volume 3; Nature Publishing Group, each of which is incorporated herein by reference.
  • the optical detector 804 is configured as a diode 808.
  • diodes 808 there can be variety of embodiments of diodes 808 that can he used.
  • the diode 808 is represented conventionally with a p- region 810 that is positioned adjacent to an n-region 812, though a variety of structures may be applicable.
  • Such p-regions 810 and n-regions 812 are typically formed " by doping according to known techniques.
  • diode or other nonlinear structures may be appropriate for certain applications.
  • planar diode multipliers For example, planar diode multipliers. Schottky diodes, field emission devices, and HEMT devices are described herembelow and in various references incorporated herein. In many cases the particular component may be designed specifically to interact with its respective one or more optical antenna elements 102
  • the magnitude of the electrical signal produced by the one or more of the optical antenna elements 102 corresponds to the amplitude of the optical wave interacting with it.
  • the electrical signal will propagate in a manner corresponding to its frequency and the structure of the optical antenna elements 102 and the electrical conductor.
  • the electrical signal is at very high frequencies, it is likely to be earned in the form of a plasmon.
  • the plasmon is guided by the electrical conductor or by the optical antenna element to, or near, the nonlinear component, where the plasmon may produce a change in an electric field in, around, adjacent to or otherwise interacting with the component.
  • the component responds to the interaction by producing a corresponding output electrical signal.
  • a variety of interacting approaches may be applicable.
  • the optical antenna elements and their associated signal processing components may include a nonlinear device such as a diode or transistor integrated with or coupled to optical antenna elements.
  • a nonlinear device such as a diode or transistor integrated with or coupled to optical antenna elements.
  • an n-region 807 of diode 808 carries an optical antenna element 102.
  • the n-region 807 is integrated into a substrate 202 that includes a p-region 810.
  • adjoining n and p-regions can form a diode, thus forming a nonlinear device.
  • nonlinear devices, such as diodes can form portions of rectification or signal processing circuitry. While the diagrammatic representation of FIG.
  • the diode 8 shows the diode being physically discrete from and carrying the optical antenna element 102, the diode may be incorporated into the diode as is noted hereinbelow.
  • the representational diode 808 of FIG. 8 includes a pn-junction, other configurations, such as those including Schortky diodes may be more appropriate in some configurations.
  • Such diodes and integration with waveguides, nanotubes, and other components are referred to .hereinbelow and in several of the references incorporated herein by reference.
  • an optical detector 804 that responds to the electrical signal induced in the optical antenna element 102 includes a transistor 908.
  • the embodiment of transistor 908 that is described with respect to FIG. 9 is a field-effect transistor (FET), as indicated by the identity of the terminals (a source 910, a gate 912, and a drain 914J 5 though other transistor configurations may be appropriate in some configurations, as noted below.
  • FET field-effect transistor
  • Hie optical antenna element 102 is coupled to the gate 912 and the source 910 and drain 914 can be biased in a conventional manner.
  • the details of biasing and other electronic circuitry can. be represented diagrammatically, as the details of the electronic circuitry will depend upon the application, frequency, and configuration. Specific examples of electronic circuitry coupled to transistor-like elements at far
  • the induced electrical signal in the optical antenna element 102 upon arrival of an optical wave at the optical antenna element, produces a change in a field, in the gate 912 of the transistor that produces a corresponding amplified, output according to principles of transistor operation.
  • the transistor may be configured for additional gain, selectivity, or interaction with the electronic circuitry.
  • the channel width and other parameters may be configured to be resonant at a frequency corresponding to the frequency of an input wave.
  • An example of transistors configured for resonant operation is described in V. Ryzh ⁇ , I. Khmyrova, M. Shur; "Terahertz photomixing in quantum well structures using resonant excitation of plasma oscillations";
  • the components of the traditional diode (see FIG. 8) or Schottky diode, or the transistor that is associated with the optical antenna element 102 (see FIG. 9) can either be formed either on, or in, the substrate 202 as shown in FIGS. 3, 4, 5a, and 5b.
  • the particular device that is selected to be associated with the optical antenna assembly may vary depending upon the application, configuration, frequency, fabrication considerations, or other considerations.
  • the particular processing or mixing devices described herein are illustrative in nature, and not limiting in scope,
  • optical antenna elements 102 as described relative to FIGS. 8 and 1 through 5 can be formed partially or entirety with metal, semiconductors, carbon, or other materials that may be compatible with fabrication processes for many types of electronic components. Consequently, portions of the optical antenna elements 102 can correspond to or be integral with the portions of one or more Scbottky diodes, transistors, or other components. For example, where an optical antenna element 102 is metal, it may be integral with or actually form an electrode of a Schottky diode.
  • signal processing techniques may be used to process and/or transfer information derived from one optical antenna assembly to another location.
  • One signal processing technique that is particularly applicable is conversion between the time domain and trie frequency domain.
  • the detected intensity values for a receiving optical antenna assembly can be sampled, and the quantized sampled values converted, such as with a Fourier Transform or Fast-Fourier Transform filter to obtain frequency domain information that is representative of the light received at all of the optical antenna elements across the receiving optical antenna assembly.
  • This frequency domain information can be processed, stored, or transferred to a different location depending upon the desired use of the receiving optical antenna assembly.
  • An inverse operation can generate a desired light signal or image with the transmitting optical antenna assembly applies frequency domain information to such a device, such that the device selectively emits the equivalent of a spatial Fourier transform of an intended image.
  • a conventional lens can act as a spatial Fourier transforming device and thus can convert the waves emitted by the optical antenna assembly to a "real world" image represented by the information applied to the optical antenna assembly,
  • the optical antenna controller 1700 as described with respect to FIG. 20 may generate the spatial frequency domain information to be applied to the optical antenna assembly, from conversion of a real world image, from an analytical source, such as optical design, modeling, or analysis software, or from information supplied from another source.
  • an analytical source such as optical design, modeling, or analysis software
  • electrical circuitry may generate a carrier signal (either an electrical or optical signal) that is used to produce the light.
  • a carrier signal either an electrical or optical signal
  • an oscillator may be used to produce a sinusoidal carrier signal and/or reference signal. Examples of oscillators operating at, or near optical frequencies can be found in J. C. Pearson, I. Mehdi, E. Schlecht, F. Maiwald, A. Maestrini, J. Gill, S. Martin, D. Pukala, J. Ward, J. Kawamura, " WJEL McGrath, WA. Hatch, D. Harding, H.G. LeDuc, JA. Stern, B. Bumble, L. Samoska, T.
  • FIG. 11 shows one generalized representation of a feedback system that may operate as an oscillator 1102.
  • Such basic diagrammatic structures are commonly described in a variety of technologies, such as those relating to control S3'stems 5 antenna systems, microwave systems, and analog circuits.
  • an input signal arrives at the summer ⁇ where it is combined with a feedback signal from a feedback element fi to produce an combined signal that drives a gain element G.
  • the gain element G amplifies the combined signal to produce an output signal VQ UT -
  • the feedback element f x may be a frequency filter so that the overall system oscillations are sinusoidal at a selected frequency.
  • While one basic form of the oscillator 1102 is presented diagrarnmatically hi FIG.11, one skilled in the art will recognize that the actual oscillator configuration will depend upon the particular application, including frequency of operation, type of gain element, desired or available quality factor Q of various components and filters, and other operational and design considerations.
  • the frequency may be determined in part or hi whole by a frequency selective component of the gain element G.
  • references to the feedback element I 1 herein may be applicable to the forward gain portion of the system, in lieu of, or in addition to the feedback portion of the system.
  • systems involving more than one feedback loop systems having a separate driving source for gain, and systems having the gain and feedback portions integral to a single component may be appropriate for ' certain applications.
  • oscillators or signal sources may be presented in a variety of other diagrammatic or conceptual representational approaches.
  • the oscillator output signal V O u ⁇ can drive one or more antenna elements described elsewhere herein.
  • the output signal V 0UT may provide a carrier signal, driving signal, or reference signal directly, or may be frequency converted to produce a carrier signal, reference signal, or driving signal for the optical antenna element.
  • FIG. 12 shows, representationally, one type of structure 1202 that can, in part, define the system frequency of oscillation and Q.
  • a molecule or other structure such as a quantum dot, which may be a separate element or may be incorporated into a larger structure, such as a crystal lattice, receives input energy.
  • the received energy may come in part from the system output, V out as shown hi FIG. 12.
  • the structure 1202 resonates at a frequency defined, in part, by its physical and electromagnetic characteristics, such as available quantum states of electrons or mass of molecules.
  • FIG. 12 is merely representational of molecular structures where a nucleus N is surrounded by electrons e-.
  • the energy levels, bond strengths, and other aspects of the molecular structure define resonances at which the molecule will naturally respond, and FIG. 12 is presented representationally for clarity of presentation.
  • oscillators need not rely on natural frequencies of molecules in many applications.
  • oscillators employing molecular or quantum dot based resonators have been produces at a variety of frequencies.
  • lasing based upon quantum dot oscillations is described in "Lasing from inGaAs/GaAs quantum dots with extended wavelength and well-defined harmonic-oscillator energy levels " G. Park, O. B. Shchel ⁇ n, D. L. Huffaker, and D. G. Deppe, Applied Physics Letters VoI 73(23) pp. 3351-3353. December 7, 1998 .
  • the feedback element fi may include a plurality of separate or integral structures, components, or, elements that provide feedback and/or frequency selectivity. As noted previously, such structures may be hi the feedback portion of the system, hi the forward gain portion of the system, or in both.
  • FIG. 11 presents the oscillator
  • other sources of a carrier signal, reference signal, or driving signal may be appropriate in many cases.
  • one embodiment of a system that mixes the reference signal with a received signal employs a separately generated reference signal at the optical frequency.
  • a laser such as a microlaser, laser diode, dye laser, or other type of known laser produces the reference signal.
  • the output signal is typically an optical beam, at a frequency on the order of tens to hundreds of terahertz.
  • the type of lasers selected may depend upon the desired wavelength, power, cost, portability or other aspects.
  • the signal from the reference source is directed toward one or rnoie of the optical antenna elements 102. As described previously j, the optical antenna elements convert energy in the incident reference beam into a reference electrical signal earned by a portion of the optical antenna element 102.
  • the signal from the reference source may be applied to tlie same optical element that is operating as a receiving optical antenna element to produce a response in the optical antenna element 102 that is a composite of the response corresponding to the received optical signal and the response corresponding to the reference optical signal.
  • An example of a reference optical signal mixed with a second signal to drive a dipole antenna is described in the article LC. Mayorga, M. Mikulics; M. Marso; P. Kordos; A. Malcoci; A. Stoer; D. Jaeger; R.
  • the signal from a reference source 1302 may be applied to optical antenna elements 102A different from the optical antenna elements 102 operating as receiving optical antenna elements.
  • the electrical signal corresponding to the received optical signal, and the electrical signal corresponding to the reference optical signal can then both be coupled to an electrical conductor 1304, such as a waveguide, component, or polariton propagating material, that produces an output that is a composite of the electrical signal.
  • an electrical conductor 1304 such as a waveguide, component, or polariton propagating material, that produces an output that is a composite of the electrical signal.
  • a reference signal may be formed according to optical irradiation of semiconductor or nonlinear optical materials that, in turn, produce polariton propagation as can be found in N.
  • FIG. 14 shows diagrammatically one embodiment of a phase comparator 1400 that includes a combined optical antenna element array 1402 and a reference waveform generator 1404 that produces a reference waveform 1407, presented as traveling left to right in FIG. 14.
  • a phase comparator 1400 that includes a combined optical antenna element array 1402 and a reference waveform generator 1404 that produces a reference waveform 1407, presented as traveling left to right in FIG. 14.
  • the diagrammatically represented components may form a portion of an optical antenna assembly, as described hereinabove.
  • Each optical antenna element 102 in the array may generate and/or receive any given phase with respect to the other optical antenna element in any desired spatial location. Control of the relative phases between the optical antenna elements can allow beamfo ⁇ irmg, gain control, or other features, as described previously.
  • the comparators Cx may include respective phase adjusters ⁇ ⁇ x, that shift the phases of the corresponding signals received by their respective optical antenna elements.
  • phase comparator may be integral to the optical antenna elements or combiners in some configurations and the phase adjusters may be integrated into a single component or a few components that may be separate from the combiners.
  • the comparators or phase adjusters may be active or passive structures.
  • phase adjusters may be positioned to control the phase of the reference signal in a receiving configuration or may be positioned to adjust the phase of the generated signals after the signals can be emitted by their respective optical antenna elements.
  • the reference waveform arrives from a direction substantially parallel to a plane containing the array of the optica] antenna elements (e.g., from left to right in FIG. 14) sucli that each of the optical antenna elements receives the reference planar waveform at a respective relative time.
  • the relative time difference will be, at least in part, a function of the inter- element spacing and the propagation velocity of the reference waveform.
  • the reference wave arrives at all of the optical antenna elements or combiners substantially simultaneously.
  • the reference waveform is presented as traveling parallel to the central direction of the generated or received waveform, though other orientations may be selected depending upon design considerations.
  • the applied reference waveform therefore moves in a generally upward direction as illustrated with respect to FIG. 15.
  • the reference waveform thus arrives orthogonally relative to the plane containing the optical antenna elements. Angles other than parallel or orthogonal to the plane containing the optical antenna elements may also be selected.
  • One approach to providing the reference waveform was described above with reference to FIG. 13, although the reference waveform may be a signal carried along a conductor, such as a wave of polaritons having defined relative phases.
  • FIG. 14 presents the reference signal as arriving from a direction perpendicular to a plane containing the optical antenna elements and FIG. 15 shows the reference signal as arriving from "behind" the optical antenna elements, in some approaches the reference signal may arrive from the "front" of the optical antenna elements. That is. the reference signal and the generated or received signal may arrive or depart - from the- same ⁇ general- side -of- the optical- -antenna assembly. - Moreover, other embodiments may employ more than one reference signal and may employ combinations of reference signals.
  • the reference waveform need not be a planar waveform., or even a substantially planar waveform.
  • non-planar waveforms may be desirable in some applications.
  • One relatively straightforward approach to producing a non-planar reference waveform is to insert a non-uniform phase delay structure, such as a non-unifoiTii phase plate or an active array of phase delay structures between the reference waveform generator 1404.
  • a non-uniform phase delay structure such as a non-unifoiTii phase plate or an active array of phase delay structures between the reference waveform generator 1404.
  • signals from the reference planar waveform generator 1404 received at different times (and as such, signals received hi different phases) among the different optical antenna elements may be monitored and adjusted, or otherwise considered.
  • the phase of a signal generated or received at a first optical antenna element 102 relative to the reference signal differs from the phase of a signal a second optical antenna element 102.
  • the reference waveform may be a composite formed from a set of polarit ⁇ n generators, such as a set of emissive structures or a set of apertures in a material.
  • the phase adjusters A ⁇ n can he controlled 'by an electronic controller to include, e.g., a general-purpose computer, a microcontroller, a microprocessor, an application-specific integrated circuit, or any other type of computer-based, logic-based, mechanical controller, electro-mechanical controller, or other type of a controller.
  • the controller can optionally have input from the user to control the bearofo ⁇ rung, beam steering, or other operations.
  • Phase adjusting of signals may be accomplished according to a variety of known techniques that r ⁇ ay be adapted to the frequencies herein. In a straightforward case, a fixed phase mask may be defined to provide a passive form of phase control.
  • the phase adjusters ⁇ ⁇ R of at least one of the two optical antenna elements 102 can be adjusted to reduce, eliminate, or otherwise control the in relative phases.
  • the amount, direction, and other aspect of the relative pliases can be determined according to the desired response of the antenna assembly 100. For example, pairs of elements may be excited and the relative minima and maxima of their farfield patterns may be determined.
  • the general gain of the optical antenna elements along paths may be monitored and the relative phases of one, two, or more of the optical antenna elements adjusted according to an intelligent searching approach to establish the beam pattern according to a determined set of criteria (e.g., side lobe levels, central lobe gain, or similar criteria.).
  • FIG. 16 shows another embodiment of phase comparator 1600 that compares, and adjusts, the phase of a reference signal that is generated " by multiple receiving optical antenna elements (instead of a reierence signal being received as in the embodiment of FIGS. 14 and 15).
  • the relative phases of the relative optical antenna elements 102 can be adjusted by adjusting the respective phase adjusters A ⁇ T .
  • the phase comparator 1600 of FIG. 16 differs from the phase comparator 1400 of FIG. 14 in that the reference planar waveform generator 1604 is configured to apply a reference wave that is perpendicular to the orientation of the optical antenna elements of the combined generating visible frequency element array 1602.
  • the reference waves can be received at each of the multiple receiving optical antenna elements at a different time corresponding to the time necessary for the reference wave to travel to each respective optical antenna element from a preceding optical antenna element
  • Optical antenna elements may be fabricated according to a variety of techniques including, but are not limited to, photolithography, lithography, nano structure growth, and attaching separately grown nano structures a 1 ⁇ -r substrate or other support.
  • Optical antenna elements may be classified as either regular or non-regular. As described above, with an this disclosure, ' the term "uniform”, pertains to regular or statistically regular arrays of optical antenna elements that extend substantially continuously across a portion of, or an entirety of, an optical antenna assembly.
  • optical antenna elements are those in which each optical antenna elements are uniformly spaced from the neighboring optical antenna element, and each optical antenna element extends substantially perpendicular to the substrate or other supporting member.
  • optical antenna element are typically minute spacing of the optical antenna elements may not be exactly regular.
  • regular pertains in many embodiments to the location of attachment of the optical antenna elements across the substrate.
  • growing optical antenna elements from a number of regularly spaced seed locations can produce a substantially regular array of optical antenna elements within an optical antenna assembly, even though many of the optical antenna elements may extend at angles other than orthogonal with respect to the substrate, as represented in FIG. 22.
  • the overall resulting operating characteristics of many embodiments of the optical antenna assembly may have substantially repeatable, predictable and/or determinable electromagnetic characteristics .
  • a large number of other fabrication techniques can be used to produce regular arrays of optical antenna elements, For example, lithographic patterning techniques, e-beam lithography, and nano structure epitaxial growth can be utilized. Grown nanostmctures can be separated, and reattached to the supporting member to produce a statistically regular configuration of the optical antenna elements.
  • FIG. 23 Another embodiment of regular optical antenna assembly is represented in FIG. 23, in which a number of patterned rectangles 2304 are formed in a substantially horizontal configuration across the substrate or supporting member.
  • the patterned rectangles 2304 may be formed in one embodiment using lithography, photolithography, or some other etching 5 growth or other fabrication technique.
  • the spacing and dimensions of the patterned rectangles is selected to correspond to the intended operational frequency of the optical antenna elements.
  • Typical photoconductor or processing techniques can be used to produce the structures, as are generally known by those skilled in the art of semiconductor processing.
  • FIG. 23 includes rectangular optical antenna elements 2304, a variety of other structures, including those having hexagonal, circular, elliptical, or other cross-sections may be appropriate for some configurations.
  • the optical antenna elements 2304 are represented as structures that extend from a base, other structures, such as recesses, apertures, or voids or structures that extend laterally or in other directions may be suitable.
  • a number of embodiments of optica] antenna assemblies may be operable to produce waves appropriate for interferometric applications.
  • Interferome ⁇ ic applications including interferometer-based optical imaging or measurement, include telescopes, including those that have allowed astronomers to measure the diameter of stars, distance measuring, photolithographic applications, surface topology, speed measurement, surface topology measurements, distance measurements, and a variety of other applications.
  • the configurations of such interferometers can apply similar principles to those described with respect to FIGS. 6 and 7.
  • coherent techniques can be configured to provide a variety of embodiments of a holographic projector, as described below, including holographic devices for image presentation.
  • One embodiment of optical interferometers described with, respect to this disclosure includes solid state interferometers.
  • Such solid- state optical-domain interferometers operate by rnixing the received light, and extracting phase information from the mixed signal without leaving the optical domain.
  • One aspect of certain embodiments of the optical interferometers can be characterized as operating as "digital interferometers."
  • a digital optical interferometers includes a digital computation device that selectively controls the amplitude and/or phase of a number of the optical antenna elements. The selected relative phase and/or amplitude may be determined analytically, through, calculations or other approaches, may be determined empirically, or may be retrieved from memory.
  • solid state optical-domain interferometers can be micro electromechanical system (MEMS ' ) based. In another embodiment, such solid state optical -domain interferometers can be configured to operate relying upon non-MEMS optical switching techniques.
  • MEMS ' micro electromechanical system
  • the data is generated by capturing an image, including pliase information with an optical antenna assembly-based device or other type of holographic device.
  • a variety of numerical techniques may be applied to produce the digital data for captured ; displayed, or projected images.
  • each optical antenna element produces a signal indicative of an airiving wave
  • the input is sampled, typically at a frequency approaching, substantially equaling, or exceeding the frequency of the received light, and the sampled data is processed digitally.
  • Computer techniques and hardware continue to increase processing speeds to further improve the accuracy and performance of the digital imaging.
  • the data or information may he captured at a first location, or set of locations, and then propagated to a. second location where an image is presented, as a display or holographically presented image.
  • the data or information to be generated may be compressed or replaced or supplemented by representative data to increase the speed or reduce system burden for information transmission.
  • a receiving optical antenna assembly may operate similarly to a miniaturized so-called Keck telescope or a very large array (VLA) radio telescope employing waves at optical frequencies,
  • Certain techniques described herein, relating to interferometers, can also be applied to design and construct cameras that can be configured as detectors, as described above.
  • the basic interferometer approach could therefore be applied to detectors formed from a regular or non-regular array of optical antenna elements or sets of arrays of optical antenna elements.
  • the dimensions of the array may range from postage stamp size to billboard size, and even outside of these dimensions.
  • the optical antenna elements of the optical antenna assembly can be fabricated to be self-supporting, and it may be appropriate to fabricate the substrate separately from the optical antenna elements. In other embodiments, the optical antenna elements can be supported separately from a substrate or set of substrates.
  • One embodiment of the receiving optical antenna assembly can be configured to form one embodiment of an extremely "thin" imager.
  • the operational circuitry can be disposed in a separate structure or may have integrated operational circuitry.
  • the imager may be configured as a portion of a camera that may allow the camera to have features different from conventional cameras.
  • additional portions of the optical antenna assembly such as a phase control assembly can provide directionality or gain that can supplement or replace some portion of the conventional focusing optics in a camera.
  • the imager functionality may be sufficient to completely replace the conventional optics.
  • the imager ' functionality may incorporate a combination of conventional optics and an array of optical antenna elements.
  • the optical antenna-based camera can be configured with a thickness corresponding to the thickness of a semiconductor-based chip integrated into the camera (e.g., having dimension on the order of one or a few mm), and depending upon the application may have an acceptable effective aperture size, focal length or other properties.
  • digital sampling provides an effective Fourier Transform by conttOllmg/activating selected elements or phase controls. This may allow for a self-correlating optical imaging device. " While above descriptions include periodically spaced arrays of elements, other configurations may be selected. In one embodiment, one or more optical antenna elements form an annular ring on a substrate as presented diagrammatically below with respect to FIG. 17.
  • phasel taps 1702 provides a discrete set of phase directions that can adjust the relative pJiase. This can be viewed as a phase scanning version of pixels.
  • the set of taps in effect defines the "phasels" that mix light from various parts of the ring of optical antenna elements. The number and spacing of the phasels determine the -angular resolution, in part.
  • phasels taps can be configured as the ⁇ -adjusts that rely upon delay lines ' whose delay time can be individually modified.
  • Another approach to phase control involves physically modifying the relative positions or dimensions of the optical antenna elements 102.
  • Yet another aspect of the ⁇ -adjusts 104 includes approaches that control relative, signal delays with something other than physical length (e.g., altering material properties, constructing waveguides with reduced propagation velocities, etc.).
  • an optical antenna assembly— based device employs scanning techniques.
  • an image is displayed or captured by scanning and controlling a pixel by pixel basis.
  • Scarming may. be by a physical device, such as a MEMS, acoustooptic, or similar scanner, may be implemented by controlling phase and amplitude of the signals at each respective optical antenna element, or may be a combination of both.
  • Many signal switching or modulation techniques can provide selectivity of signals from respective ones or groups of optical antenna elements.
  • one exemplary approach applies interference • of signals, with a structure such as a Mach-Zender interferometer to selectively transmit some or all of the signal from respective optical antenna elements to the respective desired locations.
  • energy is traveling, for example, from the left optical antenna ' element 102A (left to right) mixes with a signal from the right optical antenna element 102. If the signals have the same amplitude and are a half wavelength out of phase at a given location, to a first order, the net signed at the location will be substantially zero. The amplitude will vary depending upon the amplitude of the received signal relative to the amplitude of the reference signal, and/or the relative phases of the signals.
  • the optical antenna assembly may be- desired in some embodiments of the optical antenna assembly, to use a plurality of antenna assemblies, each having a respective field of regard.
  • Each of the antenna assemblies may have a fixed field of regard, or may be scannable.
  • the respective fields of regard may be non-overlapping or partially overlapping.
  • the relative phases may be varied within a smaller range as compared to the phase ranges corresponding ' to addressing a larger field of regard.
  • Directing respective optical antenna assemblies at respective orientations can allow an overall system to monitor a wide range of fields of view or to emit light over a relatively wide range.
  • the size of the arrays of optical antenna elements may allow a plurality of arrays to be assembled in a single unit or a few units. This may enable a compact system with a relatively large field of view.
  • the combiner 106 as described with respect to FIG. I 3 is configured to mix the input from any group of optical antenna elements having the desired combination of phase delays between a minimum value and a maximum value.
  • One relatively simple approach to increasing the response speed of the phasel taps includes providing each of the pliasel taps with a set of discrete phase delays, each coi ⁇ espoi ⁇ ding to respective a substantially fixed angular increment or relative phases.
  • the relative phases between respective optical antenna elements 102 can be adjusted by selectively coupling one or more of the discrete phase delays.
  • the output down- converted signal is then processed with appropriate electronic circuitry.
  • the electronic circuitry includes an analog-to- digital (A/D) converter that produces a digital signal representative of the down-converted signal. While the described rniplementation employs electronic circuitry including the A/D converter, a variety of other approaches to processing or otherwise handling downconverted signals may be appropriate, including analog filtering, sampling, or other known approaches.
  • an array of optical antenna elements may be arranged in a pattern other than an NxN matrix where each location includes one or more antenna elements.
  • an array of optical antenna elements may be arranged, according to an NxN matrix of positions, with one or more of the positions in the matrix being empty, hi some cases, a substantial portion, which may " be more than half of the positions, may be empty.
  • the positioning, response, design and other features of such a design may be determined according to techniques for sparse-array antenna structures. Examples of such analyses may be found, for example, in Athley Optimization of Element Position for Direction Finding with Sparse Arrays, self-identified as published at IEEE Proceedings of the 11 th Workshop on Statistical Signal Processing, Aug. 6-8 2001 (Singapore).
  • a less than full (two-dimensional) array of optical antenna elements may simplify fabrication ' and computation in some applications, while providing substantially the same information as a full array of optical antenna elements.
  • a more sparsely populated array may address substantially the same field of view and acquire substantially the same information by sequentially addressing a set of fields of view.
  • such an array includes a set of associated ⁇ -adjusts 104 configured as phasel taps, or individually-controllable delay lines, as described with respect to FIGS. 1 and 2.
  • the output from the different relatively few sets of the optical antenna elements can be combined to produce a set of information that approximates that of a more densely populated array.
  • a number of embodiments of the optical antenna assembly may include arrays of optical antenna elements that have periodic or aperiodic spacing of the optical antenna elements. Selection of periodic or aperiodic spacing, the inter-element spacings, or the selection of patterns may depend in part upon the shape, sidelobes, gain, complexity, or other design considerations. For example, in some approaches gain or antenna beam pattern may be directed toward high directionality to allow communication between two locations at relatively low power. This may reduce the likelihood of third part)' detection or reduce power consumption in some applications.
  • optical antenna elements may be formed directly atop a semiconductor wafer.
  • a portion of the electronic circuitry or portions of the antenna assembly may be formed integral to the semiconductor wafer.
  • a plurality of optical antenna elements may be are arranged to form a pattern that is generally in trie shape of an annular ring, which may be generally circular or another shape.
  • the ammlar ring generally follows the periphery of at least a portion of the chip, fn such a configuration some portion of the control circuitry or other portions of the antenna assembly, such as phase adjusters, mixers, or combiners, that is associated with the antenna elements is partially or wholly surrounded by the annular ring.
  • the effective diameter or other cross sectional dimension of the annular ring thereby defines the effective aperture of the optical antenna elements.
  • Regularly shaped arrays are not limited to NxN squares or MxN or NxN rectangular arrangements. Moreover, the arrangements are not limited to circular rings, squares, or rectangles. A variety of arrangements may be developed according to antenna design principles in a variety of two- dimensional or three dimensional configurations.
  • patterns of optical antenna assemblies include, but are not limited to, sets of optical antenna elements as arranged as an extended dipole, a sinusoidal shape, a repeatable curve, annular rings, or other mathematically or otherwise analytically definable arrays.
  • Other embodiments of optical antenna assembly configurations include, but are not limited to, non-repeatable curves, portions of the optical antenna assembly formed on different layers, portions of the optical at the assembly at different elevations (e.g., on a non-level layer), curved or O- shaped structures, discontinuous portions of optical antenna assemblies that form capacitive, inductive, or matching structures, etc.
  • the optical antenna elements are not necessarily limited to positioning on a single level and patterns may subtend more than one level.
  • the optical antenna elements may be arranged on different layers of substrate or may be distributed irregularly in depth.
  • FIG. 17 shows one example of an array of optical antenna elements 102 arranged in non-regular pattern.
  • the number of optical antenna elements forming the ring may range from one pair to a large number (tens, hundreds, thousands, or more), depending upon various design considerations, such as power, resolution, cost, size, manufactaability, or other factors.
  • the layouts of the optical antenna elements 102 as described with respect to FIGS. 17 to 19 may be intended to be configured as either receiving or generating optical antenna elements or element that may both generate and receive, as described with, respect to FIGS, l and 2.
  • each, optical antenna assembly 100 The diameter of the ring approximates the effective aperture of each, optical antenna assembly 100.
  • Circuitry or other elements may be located adjacent to or integral with the respective optical antenna elements in some configurations.
  • delay lines 1702 link optical antenna elements to an optical antenna controller 1700.
  • optical antenna elements that are oppositely positioned utilize respective pairs of delay lines 1702, though other arrangements may be selected.
  • the delay lines may " be fixed or may have variable , delays.
  • each dela ⁇ ? line has one or more phase! taps (e.g., the ⁇ -adjust 104 as described with respect to FIGS. 1 and 2) that can he switched on or off under control of the cental circuitry or under other control.
  • each opposed pair of optical antenna elements can be operated in tandem.
  • the optical antenna controller 1700 can operate using as many pairs of optical antenna elements 102 as are desired, from one pair to the number of pairs of optical antenna elements that can be present in the optical antenna assembly 100,
  • HG. 18 illustrates another embodiment of the optical antenna assembly 100 that includes another non-regular pattern of optical antenna elements 102 in two generally spiral-shaped patterns 1802, 1804.
  • Each- optical antenna element 102 in each spiral-shaped pattern has a respective distance from a geometric center of the pattern that increases as the distance along the spiral increases.
  • the distance to each optical antenna element generally increases as one follows each spiral-shape pattern 1802, 1804 in a counter-clockwise direction, though other spiral shapes and directions may be appropriate depending upon the configuration.
  • FIG. 19 illustrates yet another embodiment of the optical antenna
  • one pair of opposed optical antenna elements 102 can be connected or operationally coupled by respective conductors 1902 and 1904 to the optical • • antenna controller 1700.
  • ⁇ antenna elements 102 defines a first aperture spacing 1910. Another pair of opposed optical antenna elements 102 are connected or operationally coupled by respective conductors 1906 and 1908 to the optical antenna controller 1700. The spacing of the second pair of opposed optical antenna elements 102 defines a . second aperture spacing 1912. The embodiment of optical antenna assembly 100 as described with respect to FIG. 19 can therefore utilize the first aperture spacing 1910 and/or the second aperture spacing 1912.
  • optical antenna elements While the number of optical antenna elements, or pairs of opposing optical antenna elements, shown in the figures, is presented herein as a one or a few elements or pairs of elements, it is to be understood, that the number and exact configuration of the optical antenna elements within any particular optical antenna assembly is a design choice, and variations thereof are within the intended scope of the present disclosure. In addition, other regular patterns, non-regular patterns, or mixtures thereof of optical antenna elements to form an array are within the intended scope with present disclosure.
  • FIG. 20 shows one embodiment of the optical antenna controller 1700, as described above with respect to FIGS. 17, 18, and 19.
  • the optical antenna controller 1700 whose components are shown in FIG. 3, comprises a central processing unit (CPU) 2002, memory 2004, circuit portion 2006, and input output interface (I/O) 2008 that may include a bus (not shown).
  • the optical antenna controller 1700 can be a general-purpose computer, a microprocessor, a microcontroller, or any other known suitable type of computer, controller, or circuitry that can be implemented on hardware, software, and/or firmware.
  • the CPU 2002 performs the processing and arithmetic operations for the optical antenna controller 1700.
  • the optical antenna controller 1700 controls the signal processing, computational, timing, and other processes associated with generating or receiving light from the optical antenna assembly 100.
  • RAM random access memory
  • ROM read only memory
  • the bus provides for digital information transmissions between CPU 2002, circuit portion 2006, memory 2004, and I/O 2008.
  • the bus also connects I/O 2008 to the portions of the optical antenna assembly 100 that either receive digital information from, or transmit digital nrformation to, though one or more optical antenna elements 102.
  • I/O 2008 provides an interface to control the transmissions of digital information between each of the components in the optical antenna controller 1700. I/O 2008 also provides an interface between the components of the optical antenna controller 1700 and different portions of the optical antenna assembly 100.
  • the circuit portion 2006 comprises all of the other user interface devices (such as display and keyboard), hi another embodiment, the optical antenna controller 1700 can be constructed as a specific-purpose computer such as an application-specific • integrated circuit (ASIC), a microprocessor, a microcomputer, or the like.
  • ASIC application-specific • integrated circuit
  • multiple layers of the optical antenna assembly are also provided.
  • the layers may be substantial copies of each other or may have differing configurations, spacing, properties, or other features.
  • the effective width of the annular ring of the optical antenna elements can be adjusted by adjusting the number of active optical antenna elements that can be contained in each row, or alternatively by activating or deactivating certain ones of multiple annular rings of the optical antenna elements.
  • the optica] antenna controller 1700 can be configured to activate or deactivate certain ones of the optical antenna elements.
  • the configuration and element density of the array of optical antenna elements 102 within the optical antenna assembly 100 can be controlled extremely quickly by some programming of the optical antenna controller 1700.
  • Replication of certain ones of the optical antenna elements or redundancy may also provide fault tolerance, compensate for physical imperfections, reduce effects of contaminants, such, as dust or dirt, add wavelength selectivity., or provide other design freedoms.
  • Reflective, refractive, phase delay, diffractive and/or other optical techniques may be combined with the optical antenna assembly and approaches described herein.
  • refractive lenses may be positioned to provide a curvature to waves arriving at the array of optical antenna elements or a wavelength selective filter may reduce light at certain wavelengths to augment wavelength selectivity of the optical antenna assembly.
  • a scratch-proof coating above one, or an array of, the optical antenna elements to protect and ensure the continued operation of the optical antenna elements.
  • a coating of a suitable covering material such as artificial sapphire, silicon, or diamond can be deposited or otherwise positioned above a any portion of, or substantially all of, the array of optical antenna elements.
  • a coating, such as diamond may be provided over both sides while providing continued optical antenna element operation.
  • control circuitry or other circuitry may be integral to or positioned in close proximity to the antenna assembly, and subsequently protected by such coating. The concepts of the coating can be sufficiently straight-forward and self-explanatory and are not displayed in any figure.
  • An optical system 250 shown diagrammatically in FIG. 21 includes " both a generating optical antenna assembly 100, which may be the same as that described with respect to FIG. 2, that provides illumination to an object 252. Additionally, the embodiment may include a receiving optical antenna assembly 100, such as that described with respect to FIG. I 5 that can capture light that is reflected from the surface of the illuminated object 252. As represented diagrammatically in the optical system 250, light generated from a generating optical antenna element 102a illuminates an object 252. A second optical antenna element 102b then captures a portion of light reflected from the object.
  • FIG. 21 includes " both a generating optical antenna assembly 100, which may be the same as that described with respect to FIG. 2, that provides illumination to an object 252. Additionally, the embodiment may include a receiving optical antenna assembly 100, such as that described with respect to FIG. I 5 that can capture light that is reflected from the surface of the illuminated object 252. As represented diagrammatically in the optical system 250, light generated from a generating optical antenna element 102a illuminates an object 252. A
  • each optical antenna element 102a, 102b may operate as both a signal generator and a signal receiver.
  • the simplified representation is presented herein for clarity of presentation.
  • the optical antenna assembly 100a is configured to concentrate optical energy or direct optical energy toward one or more regions, as described previously, the optical antenna assembly can selectively illuminate one or more spatial locations or angular ranges.
  • the receiving optica] antenna assembly 100b can receive light selectively from one or more regions or angular ranges.
  • a single optical antenna assembly may be configured to selectively direct optical energy to and receive optical energy from selected spatial locations or angular ranges.
  • a combined illumination and reception technique using the optical antenna assemblies can be configured to operate similarly to an optical range finder or LIDAR type of system.
  • the selectivity, gain, or other operational aspects may ⁇ be adjusted by selective polarization or by adding additional optical structures, such as diffractive elements, lenses, or other known optical components. While the above embodiment has been, described in many cases as a coherent system, in some cases, an optical antenna assembly can be adapted to operate with non-coherent or only partially coherent light energy.
  • illumination or illuminated imaging in the optical domain is either broadband (e.g., a camera flash that outputs light to having a wide mixture of light frequencies such as white light), or narrowband (i.e. light produced with a laser that has one, or a small number of, frequencies).
  • an optical antenna assembly can be configured to provide or receive light selectively from two, three, or more wavelength bands.
  • the bands may be primary color bands, such as red, green, and blue wavelengths.
  • a multiband approach such as light of the visible and/or near-visible frequencies, can also be used in various image capture or sensing applications.
  • the antenna element sizes, spacings, orientations, and other characteristics can be optimized according to design criteria.
  • sets of antenna elements may be - devoted to each wavelength range.
  • wavelengths in the far- infrared and into the millimeter wavelength range may penetrate materials to depths different from and, in some cases, greater than visible wavelengths.
  • wavelength bands may be chosen for example to image objects or augment imaging of objects.
  • wavelengths on the order of one or a few millimeters may permit imaging at depths different from those of visible wavelengths.
  • photolithographic techniques or other fabrication techniques pe ⁇ nit ultraviolet implementations may be realized.
  • optical antenna elements can be included in such embodiments of the communication system as teleconiiiiunication systems, computer systems, audio systems, video systems, teleconferencing systems, and/or hybrid combinations of certain ' ones of these systems.
  • the embodiments of the status indicator as described with respect to this disclosure are intended to be illustrative in nature, and are not limiting its scope.
  • an implemeiiter determines that speed and accuracy are paramount, the implementer may opt for a mainly hardware and/or firmware vehicle; alternatively, if flexibility is paramount, the implementer may opt for a mainly software implementation; or, yet again, alternatively, the implementer may opt for some combination of hardware, software, and/or firmware.
  • the processes and/or devices and/or other technologies described herein may be effected, none of which is inherently superior to the other in that any vehicle to be utilized is a choice dependent upon the context in which the vehicle will be deployed and the specific concerns (e.g., speed, flexibility, or predictability) of the implementer, any of which may vary.
  • ASICs Application Specific Integrated Circuits
  • FPGAs Field Programmable Gate
  • a signal bearing media include, but are not limited to, the following: recordable type media such as floppy disks, hard disk drives, CD ROMs, digital tape, and computer memory; and transmission type media such as digital and analog communication links using TDM or IP based communication links (e.g., packet links).
  • recordable type media such as floppy disks, hard disk drives, CD ROMs, digital tape, and computer memory
  • transmission type media such as digital and analog communication links using TDM or IP based communication links (e.g., packet links).
  • any two components so associated can also be viewed as being “operably connected”, or “operably coupled”, to each other to achieve the desired functionality, and any two components capable of being so associated can also be viewed as being “operably couplable”, to each other to achieve the desired functionality.
  • operably couplable include but are not limited to physically mateable and/or physically interacting components structure and/or wirelessly iiiteractable and/or wirelessly interacting components or structures and/or logically interacting and/or logically iiiteractable components or structures and/or electromagnetically interactable and/or electromagnetically interacting components or structures.

Abstract

L'invention porte sur un ensemble d'antenne optique comportant plusieurs éléments d'antenne optique, chaque élément d'antenne optique étant disposé selon une répartition régulière et étant porté par un corps de support. La répartition régulière des éléments d'antenne optique n'est pas uniforme. Certains des éléments d'antenne optique sont configurés pour réagir à au moins une onde lumineuse.
PCT/US2006/042123 2005-10-31 2006-10-27 Ensemble d'antenne optique WO2007053478A2 (fr)

Applications Claiming Priority (8)

Application Number Priority Date Filing Date Title
US11/263,539 US7957648B2 (en) 2005-02-28 2005-10-31 Electromagnetic device with integral non-linear component
US11/263,540 2005-10-31
US11/263,554 2005-10-31
US11/263,656 2005-10-31
US11/263,554 US20070210956A1 (en) 2005-02-28 2005-10-31 Optical antenna with phase control
US11/263,539 2005-10-31
US11/263,540 US20060239686A1 (en) 2005-02-28 2005-10-31 Electromagnetic device with frequency downconverter
US11/263,656 US7489870B2 (en) 2005-10-31 2005-10-31 Optical antenna with optical reference

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WO2007053478A2 true WO2007053478A2 (fr) 2007-05-10
WO2007053478A3 WO2007053478A3 (fr) 2009-04-30

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US20190025408A1 (en) * 2017-07-24 2019-01-24 Samsung Electronics Co., Ltd. LiDAR SYSTEM AND METHOD OF DRIVING THE SAME
EP3435377A1 (fr) * 2017-07-24 2019-01-30 Samsung Electronics Co., Ltd. Système de lidar et son procédé de commande
CN109298427A (zh) * 2017-07-24 2019-02-01 三星电子株式会社 光检测和测距***及其驱动方法
KR20190011122A (ko) * 2017-07-24 2019-02-01 삼성전자주식회사 라이다 시스템 및 이의 구동 방법
US11119191B2 (en) 2017-07-24 2021-09-14 Samsung Electronics Co., Ltd. LiDAR system and method of driving the same
KR102434702B1 (ko) * 2017-07-24 2022-08-22 삼성전자주식회사 라이다 시스템 및 이의 구동 방법
CN109298427B (zh) * 2017-07-24 2023-09-15 三星电子株式会社 光检测和测距***及其驱动方法

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