WO2000072042A1 - Orientation dependent radiation source - Google Patents
Orientation dependent radiation source Download PDFInfo
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- WO2000072042A1 WO2000072042A1 PCT/US1999/011449 US9911449W WO0072042A1 WO 2000072042 A1 WO2000072042 A1 WO 2000072042A1 US 9911449 W US9911449 W US 9911449W WO 0072042 A1 WO0072042 A1 WO 0072042A1
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- radiation
- mask
- source
- axis
- orientation
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S5/00—Position-fixing by co-ordinating two or more direction or position line determinations; Position-fixing by co-ordinating two or more distance determinations
- G01S5/16—Position-fixing by co-ordinating two or more direction or position line determinations; Position-fixing by co-ordinating two or more distance determinations using electromagnetic waves other than radio waves
- G01S5/163—Determination of attitude
Definitions
- the present invention relates to radiation sources, and more particularly to an orientation dependent radiation source, the orientation of which may be determined about one or more axes of rotation.
- Conventional radiation sources include "primary" sources, such as acoustic or electromagnetic wave transmitters, as well as “secondary” sources of radiation, such as reflectors which reflect radiation based on some incident radiation. While both conventional primary and secondary radiation sources are employed in a wide variety of applications, many conventional sources are not constructed so as to facilitate a determination of an orientation of the source, or an orientation of an object to which the source is coupled, with respect to some reference position. In particular, conventional primary orientation dependent sources which direct radiation to a particular observation area and facilitate the determination of the orientation of the source from the observation area are not known. Moreover, conventional orientation detection systems, which employ secondary radiation sources such as reflectors, are mostly limited to the determination of orientation in a single dimension, or about one axis of rotation.
- orientation detection systems including those systems which are constructed so as to facilitate a determination of orientation in more than one dimension, typically employ complex image processing techniques and equipment which process signals that are received from a group of radiation sensors arranged in a line, or dispersed throughout an observation area. Such radiation sensing configurations are often expensive and may require large observation areas for deployment, rendering such orientation detection systems impractical for many applications.
- the present invention is directed to methods and apparatus for producing orientation dependent radiation, and orientation detection systems employing such methods and apparatus.
- an orientation dependent radiation source includes a first mask to substantially block radiation, wherein the first mask defines an observation surface and includes a first plurality of openings through which radiation is capable of passing.
- the orientation dependent radiation source also includes a second mask coupled to the first mask.
- the second mask includes a second plurality of openings offset relative to the first plurality of openings such that radiation passing through at least the first plurality of openings produces an orientation dependent radiation pattern on the observation surface.
- the orientation dependent radiation pattern has at least one detectable centroid that varies in position across the observation surface based on a rotation angle of the first and second masks about at least one axis of rotation.
- an orientation detection system includes one or more orientation dependent radiation sources to direct orientation dependent radiation to an observation area.
- Each orientation dependent radiation source is constructed and arranged so as to facilitate a determination, from the observation area, of a rotation angle of the source about at least one axis of rotation based on the orientation dependent radiation.
- the system also includes one or more radiation sensors located within the observation area to detect the orientation dependent radiation.
- each orientation dependent radiation source includes a primary radiation source.
- a method for producing an orientation dependent radiation pattern on an observation surface includes a step of varying a surface area of a radiation source exposed through the observation surface, in response to a rotation of the observation surface about at least one axis of rotation, to produce at least one detectable centroid having a position that varies across the observation surface corresponding to the rotation.
- FIGS. IA, IB, and 1C are diagrams showing top views of an orientation detection system according to one embodiment of the invention.
- Fig. ID is a front view of an orientation dependent radiation source according to one embodiment of the invention.
- Fig. 2 is an enlarged front view of a portion of the orientation dependent radiation source shown in Fig. ID;
- Fig. 3 is a side view of the orientation dependent radiation source shown in Fig. ID according to one embodiment of the invention.
- Figs. 3A-F are side views of the orientation dependent radiation source shown in Fig. ID, according to other embodiments of the invention.
- Fig. 4 is a top view of the orientation dependent radiation source shown in Fig. ID;
- Figs. 5 A and 5B are front views of the orientation dependent radiation source of Fig. ID, illustrating orientation dependent radiation patterns produced in response to a rotation about an axis;
- Fig. 5C is a graphical representation of the radiation patterns shown in Figs. 5 A and 5B as a function of rotation about the axis;
- Fig. 6 is a top view similar to that of Fig. 4, showing an orientation dependent radiation source having a curved geometry according to one embodiment of the invention
- Figs. 7, 8, 9, and 9A are top views showing several modifications of the orientation dependent radiation source of Fig. 4, according to various embodiments of the invention;
- Fig. 9B is a back view of the orientation dependent radiation source shown in Fig. 9A;
- Fig. 10 is a front view similar to that of Fig. ID, showing examples of different mask geometries according to various embodiments of the invention.
- Figs. 11A-C are front and side views of an apparatus according to one embodiment of the invention suitable for providing orientation dependent radiation patterns based on a rotation about two orthogonal axes;
- Figs. 12A-C are diagrams showing a relative position of two-dimensional patterns formed by first and second mask openings, respectively, in the apparatus of Figs. 11 A-C;
- Figs. 12D-E are front views of an apparatus similar to that shown in Figs. 11 A-C. having an elliptical observation surface according to one embodiment of the invention
- Fig. 13 is a top view similar to that of Fig. 4, showing another embodiment of an apparatus according to the invention which includes one or more color filters;
- Figs. 14A-C are diagrams showing a variation of the color of the radiation pattern produced by an apparatus similar to that shown in Figs. 11 A-C. according to one embodiment of the invention.
- Figs. 15A-D are diagrams showing an orientation dependent reflector suitable for a determination of orientation in one dimension, according to one embodiment of the invention
- Figs. 16A-C are diagrams showing an orientation dependent reflector suitable for a determination of orientation in two-dimensions, according to one embodiment of the invention
- Fig. 17 is a diagram similar to that of Figs. IA, IB. and 1C, showing an orientation detection system according to another embodiment of the invention.
- Fig. 18 is a top view similar to that of Fig. 4, showing an orientation dependent radiation source including a liquid crystal display, according to one embodiment of the invention:
- Fig. 19 is a diagram of an example of a volumetric orientation dependent radiation source according to one embodiment of the invention.
- the present invention is directed to methods and apparatus for producing orientation dependent radiation, and orientation detection systems employing such methods and apparatus.
- An orientation dependent radiation source produces orientation dependent radiation and directs the orientation dependent radiation to an observation area to facilitate a determination of the orientation of the source from the observation area.
- an orientation dependent radiation source produces a radiation pattern having at least one detectable centroid that varies in position across an observation surface of the source, as observed from the observation area, based on a rotation angle of the source about one or more axes of rotation.
- the orientation dependent radiation source may include one or more primary radiation sources such as acoustic or electromagnetic wave transmitters, or secondary sources such as reflectors.
- one or more orientation dependent radiation sources may be employed in a system which includes one or more radiation sensors located in the observation area to detect the orientation dependent radiation from the one or more orientation dependent radiation sources. Additionally, the orientation dependent radiation produced by an orientation dependent radiation source according to one embodiment of the invention may be visibly observable, allowing an observer to qualitatively determine the orientation of the source from the observation area.
- Fig. 1 A is a diagram showing a top view of an orientation detection system according to one embodiment of the invention.
- an orientation dependent radiation source 500 directs orientation dependent radiation 104 to an observation area 502.
- the orientation dependent radiation source 500 is constructed and arranged so as to facilitate a determination of a rotation angle 516 of the source 500 about at least one axis of rotation, based on the orientation dependent radiation 104 as observed and/or detected from the observation area 502.
- the system of Fig. IA also includes at least one radiation sensor 65 located within the observation area 502 to detect the orientation dependent radiation 104.
- Fig. IA shows two orthogonal axes 18 and 19 passing through the orientation dependent radiation source 500.
- the axis 19 passes through the orientation dependent radiation source 500 "vertically” into the plane of the figure, and is indicated in Fig. 1 A by an encircled dot on a top surface 16c of the source 500.
- the axis 18 passes through the orientation dependent radiation source 500 "horizontally,” in the plane of the figure.
- the rotation angle 516 is indicated for purposes of illustration about the vertical axis 19, although in other embodiments the orientation dependent source may be rotated about one or both of the horizontal axis 18 and the vertical axis 19, as discussed further below.
- the orientation dependent radiation source 500 shown in Fig. IA has an observation surface 106 from which the orientation dependent radiation 104 is directed to the observation area 502.
- the observation area 502 is located at a radius 508 from the vertical axis 19.
- the orientation dependent radiation source 500 has a reference position 506 about the vertical axis 19, indicated in Fig. 1 A as 0°.
- the observation area 502 is located at the radius 508 along a reference position normal 514 extending from the observation surface 106 when the orientation dependent source 500 is in the reference position 506.
- Fig. 1 A shows that the observation area 502 spans an observation angle 510, relative to the reference position 506, about the vertical axis 19.
- two observation angles 510a and 510b are indicated about the reference position 506, angle 510b indicating a clockwise rotation about the vertical axis 19 and angle 510a indicating an equivalent counterclockwise rotation about the vertical axis 19.
- the observation angle 510a or 510b is in a plane orthogonal to the vertical axis 19, which in the example of Fig. 1 A is given by the plane of the figure, and includes the reference position normal 514.
- Fig. 1 A also shows that an orientation detection system according to one embodiment of the invention may include one or more orientation independent radiation sources 30 to direct orientation independent radiation 105 to the observation area 502. While Fig. IA shows two orientation independent radiation sources 30 separate from the orientation dependent radiation source 500. in other embodiments one or more orientation independent radiation sources 30 may be coupled to the orientation dependent radiation source 500, as discussed further below.
- the one or more orientation independent radiation sources 30 direct the orientation independent radiation 105 to the observation area 502 substantially independently of the rotation angle 516 of the orientation dependent source 500.
- the orientation independent radiation 105 may be a function of the rotation angle 516 to some extent, it is so to a substantially lesser extent than the orientation dependent radiation 104.
- the orientation independent radiation 105 may serve as a reference for the orientation dependent radiation 104, as discussed further below in connection with Figs. 5A-C, and as described in U.S. Application No. 08/698,357, referenced above.
- the radiation sensor 65 located in the observation area 502 detects both the orientation dependent radiation 104 and the orientation independent radiation 105.
- Figs. IB and IC are diagrams similar to that of Fig. IA. illustrating rotation angles 520a and 520b, respectively, of the orientation dependent radiation source 500 about the vertical axis 19.
- the rotation angles 520a and 520b represent maximum rotation angles, counterclockwise and clockwise, respectively, of the orientation dependent radiation source 500 about the vertical axis 19.
- the source 500 is capable of producing orientation dependent radiation 104 which may be observed or detected from the observation area 502.
- the actual rotational angles 520a and 520b shown in Figs. IB and IC are for purposes of illustration only, and are not intended to be limiting. Examples of maximum rotation angles according to various embodiments of the invention at which the source 500 is capable of directing orientation dependent radiation 104 to the observation area 502 include, but are not limited to, angles in a range of from 45° to 90°.
- the physical movement of the source 500 is not necessarily limited by the maximum rotation angles 520a and 520b shown in Figs. IB and IC, and that according to some embodiments, the source 500 may freely rotate one or more times clockwise and counterclockwise about one or more axis of rotation.
- the rotation angles 520a and 520b are respectively indicated in Figs. IB and IC between the horizontal axis 18 of the orientation dependent radiation source 500 when the source 500 is in the reference position 506 and the rotated horizontal axes 18a and 18b.
- the rotation angles 520a and 520b are also indicated between the reference position normal 514 and rotated normals 514a and 514b, respectively, to the observation surface 106.
- the observation angle 510a or 510b which is spanned by the observation area 502 is substantially less than the maximum rotation angle 520a and 520b of the orientation dependent radiation source 500.
- the orientation dependent radiation source 500 is capable of directing the orientation dependent radiation 104 to the observation area 502 at a plurality of first rotation angles 516 about the vertical axis 19 up to the maximum rotation angle 520a or 520b.
- the observation area 502 and hence the radiation sensor 65 located within the observation area 502 may occupy a much smaller area than would be required, for example, to observe a conventional primary or secondary source emitting radiation in a direction substantially normal to an observation surface, at any angle of rotation.
- Figs. IA, IB, and IC indicate that the orientation independent radiation sources 30 are stationary with respect to the rotatable orientation dependent radiation source 500, in other embodiments one or more orientation independent radiation sources 30 may be coupled to the orientation dependent radiation source 500, and rotate with the orientation dependent radiation source 500. Notwithstanding the rotation, the orientation independent radiation sources 30 direct orientation independent radiation 105 to the observation area 502 essentially independently of the rotation angle 516.
- Figs. IA, IB, and IC each show a top view of an orientation detection system according to one embodiment of the invention, according to another embodiment these same figures may be used to describe a side view of the orientation detection system, in which the axes 18 and 19 are exchanged.
- the orientation dependent radiation source 500 may be rotated similarly about the horizontal axis 18, and hence facilitate a determination of orientation in two dimensions, or about two axes of rotation.
- the observation area 502 in such a "two-dimensional" embodiment would span a second observation angle about the horizontal axis 18 relative to the reference position 506, wherein the second observation angle is in a plane orthogonal to the horizontal axis 18 and includes the reference position normal 514.
- the orientation dependent radiation source 500 may have second maximum rotation angles clockwise and counterclockwise about the horizontal axis 18, and the second observation angle of the observation area would be substantially less than the second maximum rotation angles about the horizontal axis 18.
- the orientation dependent radiation source 500 would nonetheless be capable of directing the orientation dependent radiation 104 to the observation area 502 at a plurality of rotation angles about the horizontal axis 18 up to the second maximum rotation angles.
- the system may include one or more additional orientation independent radiation sources 30 positioned along the vertical axis 19 in a manner similar to that shown for the orientation independent sources 30 positioned along the horizontal axis 18 in Figs. lA-C. Any additional orientation independent radiation sources 30 positioned along the vertical axis 19 may or may not be coupled to the orientation dependent radiation source 500.
- Figs. ID, 2, 3, and 4 show various views of the orientation dependent radiation source 500 according to one embodiment of the invention.
- Fig. ID is a front view of the orientation dependent radiation source 500, looking onto the observation surface 106, in which the axis 18 is indicated horizontally.
- Fig. 2 is an enlarged front view of a portion of the orientation dependent radiation source 500 shown in Fig. ID.
- Fig. 3 is a side view of the orientation dependent source 500, looking onto a plane defined by an end surface 16b.
- Fig. 4 is a top view of the orientation dependent source 500 similar to that of Figs. 1A-C, looking onto a plane defined by a top surface 16c.
- source radiation refers to radiation provided by one or more primary “supply” sources, such as acoustic or electromagnetic wave transmitters, as well as radiation provided by one or more secondary “supply” sources of radiation, such as reflectors which reflect radiation based on some incident radiation.
- source radiation is generally indicated in the drawings by reference character 70.
- orientation dependent radiation refers to radiation produced by the orientation dependent radiation source 500 and emitted from the observation surface 106, and is generally indicated in the drawings by reference character 104, as shown, for example, in Figs. IA - IC.
- Figs. ID, 2, 3, and 4 show that the orientation dependent radiation source 500 according to one embodiment of the invention includes a first mask 24 to substantially block source radiation.
- Source radiation 70 is shown specifically in the views of Figs. 3 and 4. and as discussed above may be either acoustic or electromagnetic in nature, and may be in a variety of wavelength (or frequency) ranges of interest, for example, ultrasound, infrared, visible, ultraviolet, x-ray, etc.
- the first mask 24 may be made of a variety of materials that at least partially absorb, or do not fully transmit, a particular wavelength range or ranges of source radiation 70.
- first mask materials suitable for purposes of the invention include, but are not limited to. any number of acoustic and/or electromagnetic absorbers having a variety of physical sizes and forms.
- first mask materials suitable for purposes of the invention may include a variety of thin films which at least partially absorb, or do not fully transmit, the source radiation 70.
- the first mask 24 defines the observation surface 106 of the orientation dependent radiation source 500.
- the first mask 24 includes a number of openings 28 through which the source radiation 70 is capable of passing.
- the first mask 24 may include a number of mask portions 24a, 24b, 24c, etc., separated by the openings 28 and coupled together via a support structure 10.
- the support structure 10 may be a frame-like structure around a perimeter of the orientation dependent radiation source 500, to which the portions of the first mask 24 are coupled.
- the support structure 10 may be constructed and arranged as a system of beams, or as a trellis, to which the portions of the first mask 24 may be affixed in a "fence-like" manner.
- the support structure 10, as shown in Figs. ID, 2 , 3, and 4. is preferably constructed and arranged so as not to obstruct the source radiation 70 passing through the openings 28 of the first mask 24.
- the support structure 10 may be a solid substrate which is substantially transmissive of the source radiation 70.
- a transparent substrate support structure 10 may be formed from a solid material that allows substantially undistorted transmission of the source radiation 70 through the substrate support structure 10.
- the first mask 24 may include a continuously connected piece of mask material, formed on the substrate support structure 10, having a number of openings 28 formed through the mask material.
- Figs. ID, 2, 3, and 4 also show that the orientation dependent radiation source 500 according to one embodiment of the invention includes a second mask 20, generally indicated in the figures by areas shaded with vertical lines.
- the second mask 20 may be coupled to the first mask 24, for example, via the support structure 10.
- the second mask 20 may be made of a variety of materials, and includes a number of openings 27.
- the openings 27 are offset relative to the openings 28 of the first mask 24 such that the source radiation 70 passing through the openings 28 produces the orientation dependent radiation 104 shown in Figs. 1 A-C, and in particular, produces an orientation dependent radiation pattern on the observation surface 106.
- the orientation dependent radiation pattern produced on the observation surface 106 of the orientation dependent radiation source 500 by virtue of the relatively offset openings 27 and 28, includes one or more detectable centroids of radiation.
- the detectable centroids vary in position across the observation surface 106 based on the rotation angle 516 of the first and second masks 24 and 20, respectively, about at least the vertical axis 19.
- the second mask 20 is separated from the first mask 24 by a distance 23, which, as shown in the figures, may correspond to a thickness of the support structure 10.
- the area corresponding to the distance 23 between the first mask 24 and the second mask 20 may be occupied by, for example, a gas, liquid, or solid which is substantially transmissive of the source radiation 70.
- the support structure 10 may be a solid substrate which is transmissive of the source radiation 70, as discussed above.
- Figs. 3 and 4 show that the first mask 24 may be coupled to a front surface 12 of a transparent substrate support structure 10, while the second mask 20 may be coupled to a back surface 14 of the transparent substrate support structure 10.
- the second mask 20 may be arranged substantially parallel to the first mask 24, although other embodiments may not require this. Additionally, in one embodiment of the invention the distance 23 separating the first and second masks may be variable.
- Figs. 3A and 3B are side views similar to Fig. 3 which show that one or both of the first mask 24 and the second mask 20 may be coupled to a translational controller 522.
- the translational controller 522 may serve as the support structure 10 itself, as shown in Fig. 3A, or may be coupled to the support structure 10. as shown in Fig. 3B.
- the translational controller 522 may be operated to vary the distance 23 between the first and second masks.
- the support structure 10 may include an expandable and retractable cavity 524 containing a fluid or gas 526 substantially transmissive of the source radiation.
- a volume of the fluid or gas 526 in the cavity 524 may be controlled by a controllable valve 528 which couples the cavity 524 to a fluid or gas source, such as, for example, reservoir 530.
- the controllable valve 528 is operated to vary the volume of fluid or gas 526 in the cavity 524 such that the distance 23 between the first and second masks is variable.
- the substrate 10 may include a temperature sensitive material 534 such that the distance 23 varies with a substrate temperature.
- the temperature of the substrate may be controlled by a temperature controller 532.
- the temperature controller 532 controls the distance 23 based on the expansion or contraction of the temperature sensitive material 534.
- a temperature sensitive material 534 suitable for purposes of the invention includes, but is not limited to, a temperature sensitive polymer.
- the orientation dependent radiation source 500 may also include one or more orientation independent radiation sources 30, which are shown in Figs. ID and 4 as coupled to the support structure 10 to produce an orientation independent radiation pattern on the observation surface 106.
- one or more orientation independent radiation sources 30 are preferably positioned adjacent opposing end surfaces 16a and 16b of the support structure 10.
- the orientation independent radiation sources 30 may be primary radiation sources, or alternatively, may be secondary radiation sources such as reflectors.
- the orientation independent sources 30 may be reflective patches having a rectangular shape.
- one or more orientation independent sources 30 may be placed on at least one of the end surfaces 16a and 16b of the orientation dependent source 500 according to one embodiment of the invention.
- Figs. 3E and 3F which are side views similar to Fig. 3, at least a portion of one of end surfaces 16b and 16a may include one or more orientation independent radiation sources 30.
- each end surface 16a and 16b may be divided into one or more regions, and different regions on opposing end surfaces may include one or more orientation independent sources 30.
- 3E and 3F and similar embodiments having orientation independent sources on lateral surfaces, are useful in applications that require information in connection with a count or a number of full rotations of the orientation dependent radiation source 500, or alternatively, a rotation speed of the orientation dependent radiation source 500.
- the orientation dependent radiation source 500 may also include a supply radiation source 100 to emit source radiation 70, wherein the second mask 20 is disposed between the supply source 100 and the first mask 24 to substantially block the source radiation 70 except in the areas of the openings 27.
- the supply source 100 may be coupled to the support structure 10 via a variety of coupling apparatus 102, which may be selected based at least in part on the type, size and shape of the supply source 100.
- the supply source 100 may be a primary source of radiation, such as a point source that radiates the source radiation 70 multidirectionally.
- a primary supply source 100 suitable for purposes of the invention include, but are not limited to, incandescent lamps, light-emitting diodes, ultrasound transducers, antennas, and the like.
- an amount of radiation emitted by a primary or secondary supply source 100 may vary along one or more directions parallel to the horizontal axis 18 and the vertical axis 19.
- the amount of radiation emitted by the supply source 100 may vary radially from a point on the supply source 100, for example, a geometric center of the supply source, which may in some cases substantially correspond to a geometric center of the observation surface 106.
- the supply radiation source 100 shown in Figs. 3 and 4 may be a secondary radiation source, such as a reflector.
- a reflector serving as the supply source 100 may be a retro-reflector, which has the property of returning incident radiation in a direction parallel to the incident radiation.
- incident radiation is directed towards the observation surface 106 by a primary radiation source, as discussed below in connection with Fig. 7.
- the radiation incident to the observation surface 106 passes through openings 28 and 27, respectively, is incident upon the reflector serving as the supply source 100, is reflected therefrom as radiation 70, and passes through openings 27 and 28, respectively, to produce an orientation dependent radiation pattern on the observation surface 106, as discussed further below in connection with Figs. 5A-C.
- the orientation dependent radiation source 500 shown in Figs. ID, 2, 3, and 4 functions as follows. With reference again to Fig. ID, which is a front view of the orientation dependent source 500 looking on to the observation surface 106. the openings 28 of the first mask 24 are offset relative to the openings 27 of the second mask 20. which is located behind mask 24 in Fig. ID. With reference now to Figs. 5A and 5B.
- Figs. 5 A and 5B depending on the rotation angle 516 of the orientation dependent source 500 about the vertical axis 19.
- FIGs. 5 A and 5B as a z-axis orthogonal to the horizontal axis 18, only specific surface areas of the supply radiation source 100 (not shown in the view of Figs. 5A-B) are exposed through the openings 27 and 28.
- This exposure of only specific surface areas of the supply source 100 produces an orientation dependent radiation pattern on the observation surface 106 which includes one or more centroids 32, or maximum intensity radiation spots, as shown in Figs. 5A and 5B.
- the orientation dependent source 500 As the orientation dependent source 500 is rotated about the vertical axis 19, the surface areas of the supply source 100 which are exposed through the offset openings 27 and 28 changes, and as a result, the one or more centroids 32 vary in position across the observation surface 106 based on the rotation angle 516. Accordingly, by observing the position of the one or more centroids 32 along the longitudinal axis 18, the rotation angle 516 of the source 500 about the vertical axis 19 may be determined.
- the orientation dependent radiation source 500 is constructed and arranged such that at least one centroid 32 appears approximately at a geometric center of the source 500 when the rotation angle 516 is 0° and the orientation dependent radiation 104 emitted by the source 500 is viewed from a position normal to the observation surface 106.
- Fig. 5A illustrates the movement of the position 34a of the centroid 32a on the observation surface 106 as the source 500 is rotated counter-clockwise by a rotation angle 516a about the vertical axis 19, similar to the rotation shown in Fig. IB.
- two orientation independent radiation sources 30 can be seen to produce individual radiation patterns at the opposing ends 16a and 16b of the orientation dependent source 500. These orientation independent radiation patterns may serve as references for the position 34a of the centroid 32a.
- Fig. 5A illustrates the movement of the position 34a of the centroid 32a on the observation surface 106 as the source 500 is rotated counter-clockwise by a rotation angle 516a about the vertical axis 19, similar to the rotation shown in Fig. IB.
- two orientation independent radiation sources 30 can be seen to produce individual radiation patterns at the opposing ends 16a and 16b of the orientation dependent source 500. These orientation independent radiation patterns may serve as references for the position 34a of the centroid 32a.
- FIG. 5B illustrates the movement of the position 34b of the centroid 32b along the horizontal axis 18 of the observation surface 106 as the orientation dependent source 500 is rotated clockwise by a rotation angle 516b about the vertical axis 19, similar to the rotation shown in Fig. IC.
- Fig. 5C shows graphical representations of the orientation dependent radiation 104 in view from the observation area 502. including the centroids 32a and 32b formed by the surface areas of the supply radiation source 100 that are exposed at the particular rotation angles 516a and 516b, corresponding to Fig. 5 A and Fig. 5B, respectively.
- the orientation dependent radiation 104 corresponding to the rotation angle 516a depicted in Fig. 5A is indicated in Fig. 5C by dashed lines, showing the centroid 32a at the relative position 34a on the observation surface 106.
- the orientation dependent radiation 104 corresponding to the rotation angle 516b depicted in Fig. 5B is illustrated in Fig. 5C by solid lines, showing the centroid 32b at the relative position 34b on the observation surface 106.
- the fraction of orientation dependent radiation 104 in view along the observation surface 106 from the exposed surface areas of supply radiation source 100 decreases gradually away from the centroids 32a and 32b along the horizontal axis 18.
- a specific radiation pattern having one or more detectable centroids 32 is produced at one or more unique positions 34 on the observation surface 106.
- the number of detectable centroids 32 for a given rotation angle 516 is based at least in part on the manner in which the openings 28 and 27 of the first and second masks 24 and 20, respectively, are offset from each other, and the overall dimensions of the orientation dependent radiation source 500, as discussed further below.
- orientation dependent radiation source 500 shown in Figs. 1-4 has a substantially elongated shape, as indicated by horizontal axis 18, an orientation dependent radiation source according to various embodiments of the invention may have a number of geometric shapes and sizes, depending at least in part on the application for which the orientation dependent radiation source is used.
- an orientation dependent radiation source may be as small as a quarter, and may be fabricated using conventional semiconductor fabrication techniques. According to other embodiments of the invention, an orientation dependent radiation source may be as large as a conventional billboard. Additionally, an orientation dependent radiation source may have a substantially rectangular or square-shaped observation surface 106, as in one embodiment of the invention discussed below in connection with Figs. 1 1 and 12 for applications in which the rotation angle 516 may be determined about two axes of rotation. Similarly, according to other embodiments, the observation surface 106 may have a circular or elliptical shape. Moreover, an orientation dependent source itself may have a curved shape, and may be spherically or elliptically volumetric in form, as discussed further below in connection with Figs. 6 and 19.
- orientation dependent radiation source including, but not limited to, high precision orientation measurements for sporting or movement training activities, package or object orientation identification for assembly line applications, holographic memory, and topography measurements of surfaces, including ocean floors and/or land masses, which techniques may employ supply sources and radiation sensors located above the earth, such as on a satellite.
- Fig. 4 shows that the orientation dependent source 500 may have an essentially rectilinear geometry, wherein the first mask 24 is substantially planar and the second mask 20 and supply source 100 are arranged substantially parallel to the first mask
- Fig. 6 shows an example of the apparatus of Fig. 4 having a curved geometry. While Fig. 6 shows that each of the first mask 24, the support structure 10, the second mask 20, and the supply source 100 are similarly curved and substantially parallel to each other, a combination of planar and various curved geometries amongst the first mask 24, the second mask 20, and the supply source 100 may be appropriate for various applications according to other embodiments.
- orientation dependent radiation source 500 shown in Fig. 6 has a primarily convex shaped observation surface 106
- the source 500 may be constructed and arranged such that the observation surface 106 has a primarily concave shape.
- a convex or concave shape of the support structure 10 itself may enable the support structure 10 to function as a lens.
- the supply radiation source 100 may be a secondary radiation source such as a reflector.
- Fig. 7 shows such an embodiment of the apparatus shown in Fig. 4, in which the supply source 100 is a reflector.
- the orientation dependent source 500 of Fig. 7 additionally includes several features directed to "bias" or tailor the source radiation 70 reflected from the supply source reflector 100.
- a surface of the second mask 20 facing the reflector 100 may include a reflective coating 108.
- the reflector 100 may include a pattern of surface perturbations 1 10 and 1 12 arranged in a predetermined manner relative to the openings 27 of the second mask 20 and the openings 28 of the first mask 24.
- the surface perturbations may include one or more curved bumps 110 and/or one or more triangular bumps 112.
- One or both of the reflective coating 108 and the surface perturbations 110 and/or 1 12 may be employed to "condition" radiation 70 such that the orientation dependent radiation pattern including one or more detectable centroids 32 produced on the observation surface 106 is tailored in a predetermined manner.
- a combination of reflective coating 108 and surface perturbations 110 and 1 12 may be employed to enhance the reflective properties of reflector 100 by providing for multiple reflections between the second mask 20 and reflector 100 so as to increase an intensity of one or more of the detectable centroids on the observation surface 106 for particular rotation angles.
- the orientation dependent source 500 which include a reflector as the supply source 100.
- the reflector may be fabricated such that a reflectance of the reflector varies along one or both of a direction parallel to the horizontal axis 18 or a direction parallel to the vertical axis 19. In this manner, as described above in connection with Fig. 7, the orientation dependent radiation pattern produced on the observation surface 106 may be tailored so as to increase an intensity of the radiation pattern for particular rotation angles.
- the reflector 100 may be fabricated such that a granularity of the reflector varies in one or more directions parallel to the horizontal axis 18 and the vertical axis 19, such that the source radiation 70 is a specular reflection that varies in one or more directions parallel to the horizontal and vertical axis.
- the reflector 100 may be formed such that various reflective properties of the reflector vary radially from a point on the reflector 100, for example, a geometric center of the reflector 100, which may in some cases essentially correspond to a geometric center of the observation surface 106. In this manner, an intensity of the orientation dependent radiation pattern on the observation surface 106 can be made to vary radially with rotation angles about both the horizontal axis 18 and the vertical axis 19.
- the reflector 100 may also include at least one retro-reflector.
- the reflector 100 may be formed of retro-reflective material.
- retro-reflectors and retro-reflective material are distinctive property of retro-reflectors and retro-reflective material.
- a distinctive property of retro-reflectors and retro-reflective material is that radiation incident to the retro-reflector or retro-reflective material is returned in a direction parallel to the incident radiation.
- retro-reflectors and retro-reflective materials are commercially available and are suitable for purposes of the present invention.
- retro-reflectors are manufactured as thin films and may have adhesive surfaces such that the retro- reflectors may be used as strips of reflective tape.
- Other forms of retro-reflecting materials include spreadable mixtures including suspended retro-reflective particles, wherein the spreadable mixture is readily adherable to a variety of surfaces.
- Fig. 8 shows an example of the apparatus of Fig. 4 according to one embodiment of the invention, in which a secondary supply radiation source such as reflector 100 is coupled as a sheet of material to the second mask 20.
- the sheet reflector 100 may be made of retro-reflective material, as discussed above, and/or may be adhesively coupled to the second mask 20. Additionally, the sheet reflector 100 may include a retro-reflective pattern or may include a pattern of surface perturbations, as discussed above in connection with Fig. 7.
- Fig. 9 shows an example of the apparatus of Fig. 4 according to yet another embodiment, in which the reflector 100 is formed by a spreadable mixture applied over the second mask 20, wherein the spreadable mixture includes suspended retro-reflective particles.
- Figs. 9A and 9B illustrate another embodiment of an orientation dependent radiation source according to the invention in which the second mask 20 may include a plurality of polygon-shaped rods 560.
- Each polygon-shaped rod 560 shown in Figs. 9A and 9B for purposes of illustration as triangular-shaped rods, may have a plurality of faces 566, 568, and 570.
- Each rod 560 is aligned essentially parallel to the vertical axis 19 and is translatable along a direction parallel to the observation surface 106, or horizontal axis 18. Additionally, each rod 560 is rotatable about a rod axis 562 passing through a geometric center of the rod 560.
- Fig. 9A shows a top view similar to that of Fig. 4, while Fig. 9B shows a rear view of the apparatus shown in Fig. 9A.
- the embodiment of an orientation dependent radiation source 500 shown in Figs. 9A and 9B includes at least one translational and rotational controller 564 to independently rotate each rod 560 about a respective rod axis 562.
- the one or more translational and rotational controllers 564 additionally translate each rod 560 independently along a direction parallel to the observation surface 106 such that the openings 27 are offset relative to the openings 28 of the first mask 24 to provide an orientation dependent radiation pattern on the observation surface 106, as discussed above in connection with Figs. 5A-C.
- each rod 560 may be a triangular-shaped rod having three faces, 566, 568, and 570.
- a first face of each rod may include a reflector
- a second face of each rod may include a retro-reflector
- a third face of each rod may include a non-reflective material.
- the one or more translational and rotational controllers 564 may be operated such that a same face of each rod is parallel to the observation surface at any given time; namely, the second mask 20 may be formed by all the same faces of each rod 560.
- the supply radiation source 100 as shown in Fig. 4 may include a controllable, movable, micro-mirror assembly.
- a controllable movable micro-mirror assembly suitable for purposes of the invention is given by, but is not limited to, a Digital Micromirror DeviceTM (DMDTM) manufactured by Texas Instruments, and described in the Texas Instruments publication "Current Status and Future Applications for DMDTM -Based Projection Displays," authored by Larry J. Hombeck.
- DMDTM Digital Micromirror DeviceTM
- a reflective array of fast, digital light switches are monolithically integrated onto a silicon address chip (memory cell).
- Each digital light switch is an aluminum micro-mirror that can reflect light in one of two directions, depending on the state of an underlying memory cell.
- the micro-mirrors are rotated by electrostatic attraction produced by voltage differences developed across an air gap between each micro-mirror and its associated memory cell.
- the first and second masks 24 and 20, respectively are shown as essentially rectilinear structures including similar patterns of openings 28 and 27, respectively.
- Fig. 10 illustrates that, according to other embodiments of the invention, the masks 24 and 20 and their corresponding openings 28 and 27 may have a variety of arbitrary geometric shapes which are relatively offset and have a desired spatial relationship such that an orientation dependent radiation pattern is produced on the observation surface 106 having one or more detectable centroids that vary in position across the observation surface 106 based on a rotation angle of the first and second masks about one or more axes of rotation.
- Fig. 10 which is a front view of the orientation dependent radiation source 500 similar to that of Fig.
- the openings 27 and 28 are shown with a variety of shapes or profiles, including both rectilinear and curved shapes. Additionally, some or all of the openings 27 and 28 may be circular, and some or all of the openings 27 and 28 may or may not be identical, according to various embodiments.
- Figs. 12A-C serve to clarify the relative positions of the openings 27 of the two-dimensional pattern 44 and the openings 28 of the two-dimensional pattem 42. In particular, Fig. 12C shows an overlay of the two-dimensional pattern 42 on the two-dimensional pattern 44 as viewed looking on to the observation surface 106 of the apparatus shown in Fig. 11 A.
- Figs. 11 and 12 show rectilinear structures and patterns
- a variety of geometric shapes and dimensions may be suitable for both the observation surface 106 of the apparatus shown in Figs. 1 1A-C, as well as the openings 27 of the two- dimensional pattern 44 or of the openings 28 of the two-dimensional pattern 42, as discussed above in connection with Fig. 10.
- the selection of geometric shape and dimension for any of the foregoing parameters, including the arrangement of openings 27 and 28 in the patterns 44 and 42, may be dictated at least in part by the application for which the apparatus according to the invention is used.
- the observation surface 106 may have a rectangular, circular or elliptical shape.
- the patterns 42 and 44 including the shapes and positions of the openings 27 and 28, may be configured such that a first sensitivity of the position of one or more radiation centroids along the horizontal axis 18 based on a rotation of the apparatus about the vertical axis 19, is greater than a second sensitivity of the position of the one or more centroids along the vertical axis 19 based on a rotation of the apparatus about the . horizontal axis 18.
- the patterns 42 and 44 may be configured and arranged such that the converse is true.
- Figs. 12D and 12E show orientation dependent radiation sources with observation surfaces 106 having elliptical shapes, according to one embodiment of the invention.
- the horizontal axis 18 serves as a major axis of the elliptical observation surface
- the vertical axis 19 serves as the major axis of the observation surface.
- the patterns 42 and 44 may be configured and arranged such that the centroid 32 moves a first vertical distance 538a as a result of a rotation 517 about the axis i 18 that is less than a first horizontal distance 536a traveled by the centroid 32 as a result of a same amount of rotation 516 about the axis 19.
- the pattems 42 and 44 may be configured and arranged such that the centroid 32 moves a second vertical distance 538b as a result of a rotation 517 about the axis 18 that is greater than a second horizontal distance 536b traveled by the centroid 32 as a result of an equivalent rotation 16 about the axis 19.
- any of the foregoing parameters including the arrangement of openings 27 and 28 in the patterns 44 and 42. may be dictated at least in part by the application for which the apparatus according to the invention is used.
- the observation surface 106 may have a rectangular, circular or elliptical shape.
- the patterns 42 and 44 including the shapes and positions of the openings 27 and 28, may be configured such that a first sensitivity of the position of one or more radiation centroids along the horizontal axis 18 based on a rotation of the apparatus about the vertical axis 19, is greater than a second sensitivity of the position of the one or more centroids along the vertical axis 19 based on a rotation of the apparatus about the horizontal axis 18.
- the patterns 42 and 44 may be configured and arranged such that the converse is true.
- Figs. 12D and 12E show orientation dependent radiation sources with observation surfaces 106 having elliptical shapes, according to one embodiment of the invention.
- the horizontal axis 18 serves as a major axis of the elliptical observation surface
- the vertical axis 19 serves as the major axis of the observation surface.
- the patterns 42 and 44 may be configured and arranged such that the centroid 32 moves a first vertical distance 532a as a result of a rotation 517 about the axis 18 that is less than a first horizontal distance 530a traveled by the centroid 32 as a result of a same amount of rotation 516 about the axis 19.
- a "horizontal sensitivity" of the centroid 32 is greater than a "vertical sensitivity" of the centroid 32.
- the patterns 42 and 44 may be configured and arranged such that the centroid 32 moves a second vertical distance 532b as a result of a rotation 517 about the axis 18 that is greater than a second horizontal distance 530b traveled by the centroid 32 as a result of an equivalent rotation 516 about the axis 19.
- a horizontal sensitivity of the centroid 32 is less than a vertical sensitivity of the centroid 32.
- Fig. 13 shows yet another embodiment of an orientation dependent radiation source according to the invention, which has particular utility for applications in which the source radiation 70 is visibly observable.
- Fig. 13 which is similar to the top view of Fig. 4. shows that the orientation dependent source 500 may include one or more color filters 120. While Fig. 13 shows that one or more color filters 120 may be disposed between the second mask 20 and the supply source 100, the support structure 10 may be a substantially transparent substrate to which the first mask 24 and the second mask 20 are coupled, as discussed above, and the substrate support structure 10 may include one or more color filters alternatively to. or in addition to, the color filter 120 shown in Fig. 13. Furthermore, at least one of the first mask 24 and the second mask 20 may include a color filter. With reference again to Figs.
- a color filter 120 is preferably constructed and arranged such that a color 132 of the detectable centroid 32 varies as the position 34 of the detectable centroid 32 varies across the observation surface 106 of the orientation dependent source 500. as the source 500 is rotated about one or more axes of rotation.
- the color 132a of the centroid 32a varies from left to right along the horizontal axis 18 of the observation surface 106.
- the color 132A of centroid 32a of Fig. 5 A at position 34a in Fig. 5 A may be red
- the color 132b of centroid 32b at position 34b in Fig. 5B may be blue.
- one or more color filters 120 may be constructed and arranged such that the color 132 of the centroid 32 varies radially along the observation surface 106 from a point on the observation surface, such as, for example, a geometric center 140 of the observation surface 106.
- the color 132c of centroid 32c shown in Fig. 14A may be red, corresponding to a particular rotation about the horizontal and vertical axes and, hence, a particular position on the observation surface 106
- the color 132d of centroid 32d shown in Fig. 14B may be blue, corresponding to a different rotation about the axes 18 and 19 and a different position.
- Fig. 14C shows one example of a color filter 120 that may be suitable for purposes of the apparatus shown in Figs. 11A-C, and other "two-dimensional" embodiments of the invention.
- the color filter 120 of Fig. 14C includes a number of concentric regions 122, 124, 126 and 128, as in a "dart-board" configuration, each region corresponding to a particular color, for example, red, yellow, green and blue, respectively.
- the color filter 120 may provide a radially graduated spectrum of color from a point on the filter, such as the geometric center 140, to a periphery of the color filter 120.
- color filters 120 suitable for purposes of the invention include, but are not limited to, diffraction gratings, colored glass-like materials or plastics, and thin films containing a variety of dyes.
- an orientation dependent radiation source may include one or more non- uniform polarizing filters.
- non- uniform polarizing filters While a non- uniform polarizing filter is not explicitly shown in the figures, one or more such filters may be employed in an apparatus according to one embodiment of the invention, in place of, or in addition to, one or more color filters 120, and may be implemented in a manner similar to that of one or more color filters, as discussed above in connection with Figs. 13 and Figs. 14A-C.
- a non-uniform polarizing filter may be disposed between the second mask 20 and the supply source 100 or may be implemented within a substrate support structure 10.
- One or more non-uniform polarizing filters may be constructed and arranged such that a polarization of one or more detectable centroids varies as a position of the one or more centroids varies across the observation surface 106 corresponding to a rotation about one or both of the horizontal axis 18 and the vertical axis 19.
- a non-uniform polarizing filter suitable for purposes of the invention may include a number of concentric regions, wherein each region corresponds to a particular polarization.
- a non-uniform polarization filter may be radially graduated from a point on the filter, such as a geometric center, to a periphery of the polarization filter.
- non-uniform polarization filters suitable for purposes of the invention include, but are not limited to, materials incorporating birefringent crystals, retardation plates such as quartz or mica retardation plates, and dichroic sheet polarizers incorporating materials such as polymers and plastics and/or organic dyes.
- an orientation dependent radiation source may include one or more neutral density (wavelength invariant) filters having a variety of absorption and transmittance properties, or radiation densities.
- neutral density filters wavelength invariant filters having a variety of absorption and transmittance properties, or radiation densities.
- a neutral density filter is not explicitly shown in the figures, one or more such filters may be employed in an apparatus according to one embodiment of the invention, in place of, or in addition to, one or more color and/or non-uniform polarizing filters, and may be implemented in a manner similar to that of one or more color filters, as discussed above in connection with Figs. 13 and Figs. 14A-C.
- one or more neutral density filters may be disposed between the second mask 20 and the supply source 100 or may be implemented within a substrate support structure 10.
- One or more neutral density filters may be constructed and arranged such that an intensity of one or more detectable centroids varies as a position of the one or more centroids varies across the observation surface 106 corresponding to a rotation about one or both of the horizontal axis 18 and the vertical axis 19.
- a neutral density filter suitable for purposes of the invention may include a number of concentric regions, wherein each region corresponds to a particular absorption or transmittance.
- a neutral density filter may be radially graduated from a point on the filter, such as a geometric center, to a periphery of the neutral density filter.
- neutral density filters suitable for purposes of the invention include, but are not limited to, thin metallic films such as iconel, chromium, and nickel, which are particularly insensitive to wavelength.
- an orientation dependent radiation source 500 may include a lens 130 coupled to the observation surface 106.
- lens 130 may be used to adjust the observation angle 510, or "breadth" of observation area 502 from which the observation surface 106 is observed, as a function of the distance 508 between the orientation dependent source 500 and the observation area 502. While Fig. 13 shows that lens 130 has an essentially convex shape, a variety of lens types may be employed with an apparatus according to various embodiments of the invention to facilitate a variety of focusing applications.
- Figs. 15 and 16 illustrate two additional embodiments of an orientation dependent radiation source according to the invention.
- Figs. 15 A-D show an orientation dependent reflector 5 constructed and arranged similarly to the apparatus shown in Figs. ID, 2, 3, and 4.
- the specific embodiment of the orientation dependent reflector 5 shown in Figs. 15A-D includes a transparent substrate 10 having a front surface 12, a back surface 14, and opposing end surfaces 16a and 16b.
- the transparent substrate 10 is formed from a material exhibiting a hardness and smoothness suitable for depositing material thereon by way of standard thin and thick film processes commonly used in industry.
- the transparent substrate 10 may be textured so as to exhibit retro-reflecting properties (not shown) or may be sufficiently smooth to readily accept adhesive sheet portions of a large sheet of retro-reflecting material (not shown), as discussed above in connection with Fig. 8.
- a retro-reflective pattern 20 including a plurality of retro-reflecting patches 22 which are parallel aligned and rectangular in shape.
- the plurality of retro-reflecting patches 22 are positioned spatially along and perpendicular to the longitudinal axis 18 of the transparent substrate 10.
- the retro- reflecting patches 22 are formed from a spreadable suspension of retro-reflecting particles which is readily adherable to the back surface 14.
- the retro-reflecting patches 22 may be formed by portions of a retro-reflective material in sheet form.
- an opaque filter 24 which may be formed by an opaque film layer 26 having a plurality of openings 28 therein.
- the plurality of openings 28 allow radiation to pass through the transparent substrate 10 and reflect off of the plurality of retro-reflecting patches 22 positioned on the back surface 14.
- the plurality of openings 28 are in the form of parallel slits aligned perpendicular to and spatially along the longitudinal axis 18 of the transparent substrate 10.
- the plurality of openings 28 is offset relative to the retro-reflective pattern 20 formed by the retro- reflecting patches 22 to provide a reflection having one or more detectable centroids that vary in position across the front surface 12 based on the rotation of the transparent substrate 10 about at least one axis of rotation.
- only specific retro-reflecting patches 22 are exposed thereby producing the centroid of reflection, as discussed above in connection with Figs. 5A-C.
- An example of one possible construction of the orientation dependent reflector 5 shown in Figs. 15A-C is dimensionally described as follows:
- Width 0.5 (cm)
- Transparent substrate thickness 280 ( ⁇ m) Number of openings: 30
- Sensitivity 330 ( ⁇ m/deg) Percent area exposed through openings: 10% Total number of retro reflecting patches visible at one time: 1 1 Effective number of retro reflecting patches reflecting: 6.4 Effective orientation dependent reflector area: 1.06 (sq mm)
- Figs. 16A-C show another embodiment of an orientation dependent reflector 40 according to the invention which may be used to determine orientation in two dimensions or about two axes of rotation.
- the orientation dependent reflector 40 is formed similarly to orientation dependent reflector 5, shown in Figs. 15A-D.
- the plurality of openings 28 in the opaque film layer 26 are in the form of a two-dimensional pattern 42.
- the plurality of retro-reflecting patches 22 are in the form of a two-dimensional pattern
- the two-dimensional pattern 42. or the plurality of openings 28, are designed to cooperate with the two-dimensional pattern 44 of the plurality of retro-reflecting patches 22 such that exposure thereof co-varies with a specific angular orientation about one or more axes. Accordingly, for a specific angular orientation, the orientation dependent reflector 40 provides a radiation pattern across the observation surface 106 of opaque film layer 26 having one or more detectable centroids that vary in position across the observation surface, based on a rotation of the orientation dependent reflector 40 about one or both axes of rotation.
- the offset nature of the plurality of openings 28 relative to the plurality of retro-reflecting patches 22 is further evident in Figs. 16B and 16C.
- Fig. 17 shows another example of an orientation detection system according to one embodiment of the invention.
- the orientation dependent reflector 5 of Figs. 15A-D is shown coupled to an object 50.
- the system of Fig. 17 includes a primary radiation source 60 and a radiation sensor 65.
- the radiation source 60 is preferably capable of transmitting radiation indicated by arrows 70 of sufficient strength, such that reflected radiation 104 forms a radiation pattern on the observation surface 106 of orientation dependent reflector 5 having one or more centroids that are detectable by the sensor 65.
- the sensor 65 may be any one of a number of conventional sensors available for different types and ranges of radiation and, in particular, may be a human eye.
- the second mask 20 and a secondary supply source or reflector 100 may be any one of a number of conventional sensors available for different types and ranges of radiation.
- the region 552 in which the second mask 20 is formed may be constructed and arranged as a cell formed between two glass or glass-like plates, each plate having a conductive coating.
- the cell 552 is filled with a liquid crystal material.
- the liquid crystal state is a phase of matter which is exhibited by certain materials, in particular organic materials, over a particular temperature range. At one end of the temperature range, the liquid crystal material becomes a crystalline solid, while at another end of the temperature range it changes into a clear liquid.
- a primary characteristic of liquid crystal materials is the rod-like shape of their molecules. The application of electric fields to such materials tends to align the molecules in an ordered fashion to selectively allow radiation to pass through the cell 552.
- the controllable liquid crystal display 550 of the orientation dependent radiation source 500 may include one or more color filters 120. as discussed above in connection with Fig. 13 and Figs. 14A-C. In addition to, or in place of, one or more color filters 120, the controllable liquid crystal display 550 may include one or more non-uniform polarizing filters. Additionally, as an alternative to the color filters described in connection with Fig. 13 and Figs. 14A-C, the controllable liquid crystal display 550 may include other means for varying a color of one or more detectable centroids across the observation surface 106.
- the primary supply source 100 may include a pixel-oriented-type color source, such as would be employed in a computer or digital television monitor.
- a variety of commercially available color controllable transmissive liquid crystal displays may be suitable for purposes of the invention.
- Fig. 19 shows another embodiment of the invention which combines concepts and features of the invention discussed above in connection with Figs. 6, 1 1A-C, and 12A-C.
- an orientation dependent radiation source 500 may be constructed and arranged to have a spherical or elliptical volumetric shape.
- Fig. 19 shows the orientation dependent radiation 500 in the shape of a spherical volume which may be rotated about either the horizontal axis 18 or the vertical axis 19.
- a left portion of the sphere shown in Fig. 19 illustrates the first mask 24 having openings 28 arranged in a first surface pattern 542, while a right portion of the sphere shown in Fig. 19 as a cutaway view illustrates the second mask 20, including openings 27 arranged in a second surface pattern 544.
- the first and second masks 24 and 20, respectively, may be constructed and RECTIFIED SHEET (RULE 91 ) ISA EP 552 is filled with a liquid crystal material.
- the liquid crystal state is a phase of matter which is exhibited by certain materials, in particular organic materials, over a particular temperature range. At one end of the temperature range, the liquid crystal material becomes a crystalline solid, while at another end of the temperature range it changes into a clear liquid.
- a primary characteristic of liquid crystal materials is the rod-like shape of their molecules. The application of electric fields to such materials tends to align the molecules in an ordered fashion to selectively allow radiation to pass through the cell 552.
- the controllable liquid crystal display 550 of the orientation dependent radiation source 500 may include one or more color filters 120. as discussed above in connection with Fig. 13 and Figs. 14A-C. In addition to, or in place of, one or more color filters 120, the controllable liquid crystal display 550 may include one or more non-uniform polarizing filters. Additionally, as an alternative to the color filters described in connection with Fig. 13 and Figs. 14A-C, the controllable liquid crystal display 550 may include other means for varying a color of one or more detectable centroids across the observation surface 106.
- the primary supply source 100 may include a pixel-oriented-type color source, such as would be employed in a computer or digital television monitor.
- a variety of commercially available color controllable transmissive liquid crystal displays may be suitable for purposes of the invention.
- Fig. 19 shows another embodiment of the invention which combines concepts and features of the invention discussed above in connection with Figs. 6, 1 1 A-C. and 12A-C.
- an orientation dependent radiation source 500 according to the invention may be constructed and arranged to have a spherical or elliptical volumetric shape.
- FIG. 19 shows the orientation dependent radiation 500 in the shape of a spherical volume which may be rotated about either the horizontal axis 18 or the vertical axis 19.
- a left portion of the sphere shown Fig. 19 illustrates the first mask 24 having openings 28 arranged in a first surface pattern 542, while a right portion of the sphere shown in Fig. 19 as a cutaway view illustrates the second mask 20, including openings 27 arranged in a second surface pattern 544.
- the first and second masks 24 and 20, respectively may be constructed and arranged as concentric spherical shells, wherein the second mask 20 has a smaller radius than the first mask 24.
- the first and second masks may be constructed and arranged as elliptical shells.
- the orientation dependent source 500 may include a primary supply source or a secondary supply source "inside" the spherical or elliptical volume.
- such an apparatus may include a point source located within the shells, for example, at a geometric center of the concentric spherical shells formed by the first and second masks, respectively, wherein the point source supplies radiation multi-directionally to "backlight" the first and second masks.
- the apparatus may include a reflected spherical or elliptical shell coupled to one or both of the first and second masks.
- a reflective spherical shell may be concentric with the first and second masks and have a smaller radius than the second mask.
- an orientation dependent radiation source 500 may have an elliptical volumetric shape, as discussed above, or a variety of rectangular or other polygon volumetric shapes.
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- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Engineering & Computer Science (AREA)
- General Physics & Mathematics (AREA)
- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Investigating Or Analysing Materials By Optical Means (AREA)
- Length Measuring Devices By Optical Means (AREA)
Abstract
Description
Claims
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
AU42006/99A AU4200699A (en) | 1999-05-24 | 1999-05-24 | Orientation dependent radiation source |
EP99925788A EP1210616A1 (en) | 1999-05-24 | 1999-05-24 | Orientation dependent radiation source |
JP2000620376A JP2003500657A (en) | 1999-05-24 | 1999-05-24 | Azimuth-dependent radiation source |
PCT/US1999/011449 WO2000072042A1 (en) | 1999-05-24 | 1999-05-24 | Orientation dependent radiation source |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
PCT/US1999/011449 WO2000072042A1 (en) | 1999-05-24 | 1999-05-24 | Orientation dependent radiation source |
Publications (1)
Publication Number | Publication Date |
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WO2000072042A1 true WO2000072042A1 (en) | 2000-11-30 |
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Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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PCT/US1999/011449 WO2000072042A1 (en) | 1999-05-24 | 1999-05-24 | Orientation dependent radiation source |
Country Status (4)
Country | Link |
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EP (1) | EP1210616A1 (en) |
JP (1) | JP2003500657A (en) |
AU (1) | AU4200699A (en) |
WO (1) | WO2000072042A1 (en) |
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US20120114130A1 (en) * | 2010-11-09 | 2012-05-10 | Microsoft Corporation | Cognitive load reduction |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3648229A (en) * | 1970-03-23 | 1972-03-07 | Mc Donnell Douglas Corp | Pulse coded vehicle guidance system |
US3662180A (en) * | 1969-11-17 | 1972-05-09 | Sanders Associates Inc | Angle coding navigation beacon |
FR2723208A1 (en) * | 1986-06-17 | 1996-02-02 | Thomson Csf | Location/direction detection system for pilot helmet sights |
US5828447A (en) * | 1994-08-29 | 1998-10-27 | Centre National D'etudes Spatiales | Orientation location system of an observation instrument |
-
1999
- 1999-05-24 WO PCT/US1999/011449 patent/WO2000072042A1/en not_active Application Discontinuation
- 1999-05-24 JP JP2000620376A patent/JP2003500657A/en active Pending
- 1999-05-24 EP EP99925788A patent/EP1210616A1/en not_active Withdrawn
- 1999-05-24 AU AU42006/99A patent/AU4200699A/en not_active Abandoned
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3662180A (en) * | 1969-11-17 | 1972-05-09 | Sanders Associates Inc | Angle coding navigation beacon |
US3648229A (en) * | 1970-03-23 | 1972-03-07 | Mc Donnell Douglas Corp | Pulse coded vehicle guidance system |
FR2723208A1 (en) * | 1986-06-17 | 1996-02-02 | Thomson Csf | Location/direction detection system for pilot helmet sights |
US5828447A (en) * | 1994-08-29 | 1998-10-27 | Centre National D'etudes Spatiales | Orientation location system of an observation instrument |
Also Published As
Publication number | Publication date |
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JP2003500657A (en) | 2003-01-07 |
AU4200699A (en) | 2000-12-12 |
EP1210616A1 (en) | 2002-06-05 |
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