CN208270846U - Wavefront coding imaging system with adjustable phase mask - Google Patents
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Abstract
The utility model belongs to the technical field of optics, concretely relates to phase mask adjustable wavefront coding imaging system. The system can switch the phase mask form according to actual needs, thereby allowing the system to flexibly switch between conventional maskless imaging, coded imaging and more mask coding forms, and allowing the wavefront coded imaging system to have stronger flexibility. The system comprises an imaging lens, a phase mask assembly, an image detector and an image processing unit which are sequentially arranged along the transmission direction of an optical axis; the improvement is as follows: the phase mask assembly is formed by superposing two cubic square phase plates along the transmission direction of an optical axis, and the two cubic square phase plates can form a relative rotation angle by adopting two modes.
Description
Technical field
The utility model belongs to optical technical field, and in particular to a kind of adjustable wavefront coded imaging system of phase mask
System.
Background technique
The depth of field of expansion optical system always is the hot spot of academia's research, since mid-term the 1980s, though
Right panoramic method is proposed for depth of field extension, but until doctor Dowski of Univ Colorado-Boulder USA and
After Cathey professor proposes wavefront coded concept in nineteen ninety-five, field depth extending just has breakthrough truly.
By taking one dimensional optical system as an example, defocus optical transfer function OTF can pass through the auto-correlation of generalized pupil function
Operation obtains, as follows:
Wherein, u and x is normalized spatial frequency and aperture plane lateral coordinates respectively；W20It is maximum defocus wave aberration
Coefficient；K is wave number；And f then represents phase-plate general expression.
For traditional imaging systems, the f item in above formula is not present, therefore can be readily available the specific of defocus OTF
Expression formula are as follows:
It can be seen that when system is not introduced into phase-plate, OTF is very sensitive to defocus, and can be in frequency sky
Between periodically there is zero point, to cause irreversible information loss.But once invented doctor E.R.Dowski
Cube phase-plate (f (x)=α x3) be introduced on the entrance pupil face of optical system after, by static phase approximation method we just
Available one entirely different defocus OTF, as follows:
It is clear that the mould of defocus OTF, i.e. MTF are unrelated with defocus wave aberration coefficient at this time, that is to say, that cube
Phase-plate can make system MTF insensitive to defocus；Although the phase bit position of OTF and degree of blur W20It is related, as long as but adjusting
Factor-alpha processed increases, to W20Dependency degree will significantly reduce.Simultaneously most importantly, after being added to phase-plate,
MTF only has a degree of decline within effective frequency range in amplitude, and zero point or nearly zero point, i.e. system may be not present
When there is defocus, the information beyond primal system field depth, later can by digital image restoration algorithm there is no losing
Effectively to be restored.Simultaneously as phase-plate will not all impact the light passing amount and resolution ratio of system, so wavefront is compiled
Code is a kind of novel field depth extension imaging technology for differing substantially from reduced bore method, central obscuration method or apodization.
Currently, wavefront coded imaging systems are mostly applied in a static manner.That is, phase mask component is in design typification
It just can not dynamically change its physical aspect later, the encoding characteristics of system are determining at this time.In this way, no matter target to be imaged is
The no field depth beyond original imaging system, it is necessary to the sharpening for being just able to achieve image by restoring filtering algorithm.However,
The influence that noise during image restoration amplifies to restored image quality is inevitable.Therefore, when target present position not yet
When field depth beyond original imaging system, the direct imaging without encoding What You See Is What You Get should become first choice；And work as mesh
Mark present position well beyond original imaging system field depth and when its image detail being caused seriously to be lost, coded imaging adds
Powerful depth of field expansion effect will just be played by restoring filtering.
Therefore, more advanced wavefront coded imaging systems should have such ability: switch phase according to actual needs
Position exposure mask form, to allow system in routine without flexible between exposure mask imaging, coded imaging and more exposure mask coding forms
Switching.
Utility model content
The problem of for technical background, can switch according to actual needs phase the utility model proposes one kind and cover
Form membrane, so that system be allowed to be imaged in routine without exposure mask, flexibly switch between coded imaging and more exposure mask coding forms
The adjustable wavefront coded imaging systems of phase mask.
The specific technical solution of the utility model is:
The adjustable wavefront coded imaging systems of the phase mask include the imaging lens set gradually along optical axis transmission direction
Head, phase mask component, image detector and image processing unit；
It is characterized in that:
The phase mask component by two three times rectangular phase-plate be formed by stacking along optical axis transmission direction, and two three
Secondary rectangular phase-plate can form relative rotation angle using two ways；
Rectangular phase-plate is fixed three times for mode one: one, another three times rectangular phase-plate around optical axis rotation；
Mode two: two three times rectangular phase-plate around optical axis rotation, and two rectangular phase-plate rotation position is not three times
Together；
Phase mask functional form are as follows:
Q (x, y)=f1(x,y)+f2(x,y)；
Wherein, f1(x, y)=α x3+αy3；
f2(x, y)=α (xcos θ+ysin θ)3+α(ycosθ-xsinθ)3；
In formula, α is the parameter of phase distribution function, and θ represents rectangular phase-plate f three times2Relative to rectangular phase-plate f three times1
Rotation angle and θ value range be [0,360 °], x, y be normalization aperture plane coordinate, wherein x, the value range of y are equal
For [- 1,1]；
Under the premise of α is selected, different rotation angle, θs will make phase mask function Q that classical cube exposure mask, no be presented
There are exposure mask, only cube exposure mask and only cube exposure mask and asymmetric broad sense cube exposure mask in the y-direction in the x-direction,
To realize the conventional switching without between coded imaging and the imaging of effective exposure mask respectively, allow to strengthen the direction x or y as needed
Target signature, permission system are expanded between scale and restored image signal-to-noise ratio in the depth of field and are selected；Effective exposure mask at
As including classical square coded imaging three times, only coded imaging, only coded imaging and atypical wide in the y-direction in the x-direction
Adopted cube coded imaging.
Further, the classical square coded imaging three times that above-mentioned classical cube exposure mask reaches, phase mask function
For 2 α x3+2αy3, relative rotation angle θ is 0 ° or 360 ° at this time.
Further, above-mentioned to reach conventional without coded imaging two parts in phase mask component there is no exposure mask
The phase mask of introducing is cancelled out each other, and relative rotation angle θ is 180 ° at this time.
Further, the above-mentioned only coded imaging in the x-direction that only cube exposure mask reaches in the x-direction, phase mask function
For 2 α x3, relative rotation angle θ is 270 ° at this time.
Further, the above-mentioned only coded imaging in the y-direction that only cube exposure mask reaches in the y-direction, phase mask function
For 2 α y3, relative rotation angle θ is 90 ° at this time.
Further, atypical broad sense cube coded imaging that above-mentioned asymmetric broad sense cube exposure mask reaches,
Phase mask function is
(1+cos3θ)αx3+(1+cos3θ)αy3
(-sin3θ)αx3+(sin3θ)αy3
+3αx2y(cos2θsinθ-cosθsin2θ)
+3αxy2(cosθsin2θ+cos2θsinθ)；
Relative rotation angle θ is in addition to 0 °, 45 °, 90 °, 135 °, 180 °, 225 °, 270 °, 315 ° and 360 ° at this time
Other angles.
It is hereby achieved that following conclusion:
(1) when the relative rotation angle between two parts in combined type phase mask component is in 0 ° (360 °) and 180 °
When switching between two states, system will in classical square coded imaging three times and conventional without being converted between coded imaging,
To cope with different imaging requirements.
(2) when the relative rotation angle between two parts in combined type phase mask component is in 90 ° and 270 ° two
When switching between state, system only coded imaging and will converted only between coded imaging in the y-direction in the x-direction, thus
The purpose strengthened to the target signature in the direction x or the direction y or weakened may be implemented.
(3) when between two parts in combined type phase mask component relative rotation angle selection except 0 °, 90 °,
When value except 180 °, 270 ° and 360 °, phase mask component belongs to a kind of atypical broad sense rectangular phase-plate three times.Four
The size of a phase mask coefficient is directly related with relative rotation angle θ.Why it is atypical broad sense cube coding, is
Because of the x in phase mask component at this time3With y3Coefficient, x2Y and xy2Coefficient can not all accomplish it is completely the same.At this point, working as
When relative rotation angle θ value is smaller (| θ | < 10 °), asymmetrical broad sense cube coding can be used for adjusting the height for passing letter MTF
The stability of frequency value and defocus MTF.
Utility model has the advantages that
The method of the utility model solves the problems, such as that adaptability is not strong when traditional wavefront coded imaging systems static application,
It can be switched between being imaged there is no exposure mask (conventional imaging) and effectively exposure mask, to allow wavefront coded imaging system
System has stronger flexibility.Target in original imaging system field depth is in for image-forming range, routine will be switched to
Without coded imaging state, the direct imaging of What You See Is What You Get is realized.And original imaging system depth of field model is exceeded for image-forming range
Interior target is enclosed, efficient coding state will be switched to and implement wavefront coded imaging.Additionally it is possible in specific phase mask mould
It is realized under formula and scape is emphasized to expand scale deeply or emphasizes the dynamic select between restored image signal-to-noise ratio.
Detailed description of the invention
Fig. 1 is the system diagram of the utility model.
Fig. 2 a is that relative rotation angle θ takes 0 °, and α takes 30 corresponding two-dimensional phase exposure mask function distribution maps.
Fig. 2 b is that relative rotation angle θ takes 90 °, and α takes 30 corresponding two-dimensional phase exposure mask function distribution maps.
Fig. 2 c is that relative rotation angle θ takes 180 °, and α takes 30 corresponding two-dimensional phase exposure mask function distribution maps.
Fig. 2 d is that relative rotation angle θ takes 270 °, and α takes 30 corresponding two-dimensional phase exposure mask function distribution maps.
Fig. 3 a is that relative rotation angle θ removes 45 °, and α takes 30 corresponding two-dimensional phase exposure mask function distribution maps.
Fig. 3 b is that relative rotation angle θ removes 120 °, and α takes 30 corresponding two-dimensional phase exposure mask function distribution maps.
Fig. 3 c is that relative rotation angle θ removes 210 °, and α takes 30 corresponding two-dimensional phase exposure mask function distribution maps.
Fig. 3 d is that relative rotation angle θ removes 280 °, and α takes 30 corresponding two-dimensional phase exposure mask function distribution maps.
Fig. 4 a is an imaging system application example when without coding, and image-forming range is that the corresponding transmission function of 4m changes feelings
Condition.
Fig. 4 b is an imaging system application example when without coding, and image-forming range is that the corresponding transmission function of 10m changes feelings
Condition.
Fig. 4 c is an imaging system application example when without coding, and image-forming range is the corresponding transmission function variation in infinity
Situation.
Fig. 5 a is an imaging system application example when classical cube encodes, and image-forming range is the corresponding transmission function of 4m
Situation of change.
Fig. 5 b is an imaging system application example when classical cube encodes, and image-forming range is the corresponding transmitting letter of 10m
Number situation of change.
Fig. 5 c is an imaging system application example when classical cube encodes, and image-forming range is the corresponding transmitting in infinity
Function situation of change.
Fig. 6 a is an imaging system application example when only encoding in the x-direction, and image-forming range is the corresponding transmission function of 4m
Situation of change.
Fig. 6 b is an imaging system application example when only encoding in the x-direction, and image-forming range is the corresponding transmission function of 10m
Situation of change.
Fig. 6 c is an imaging system application example when only encoding in the x-direction, and image-forming range is the corresponding transmitting in infinity
Function situation of change.
Fig. 7 a is an imaging system application example when only encoding in the y-direction, and image-forming range is the corresponding transmission function of 4m
Situation of change.
Fig. 7 b is an imaging system application example when only encoding in the y-direction, and image-forming range is the corresponding transmission function of 10m
Situation of change.
Fig. 7 c is an imaging system application example when only encoding in the y-direction, and image-forming range is the corresponding transmitting in infinity
Function situation of change.
Fig. 8 a gives y direction character and is strengthened the example in (direction x apply coding).
Fig. 8 b gives x direction character and is strengthened the example in (direction y apply coding).
Fig. 9 a is an imaging system application example when asymmetric broad sense cube encodes, when relative rotation angle is 2 °,
Image-forming range is the corresponding transmission function situation of change of 4m.
Fig. 9 b is an imaging system application example when asymmetric broad sense cube encodes, when relative rotation angle is 2 °,
Image-forming range is the corresponding transmission function situation of change of 10m.
Fig. 9 c is an imaging system application example when asymmetric broad sense cube encodes, when relative rotation angle is 2 °,
Image-forming range is the corresponding transmission function situation of change in infinity.
Figure 10 a is an imaging system application example when asymmetric broad sense cube encodes, when relative rotation angle is 5 °,
Image-forming range is the corresponding transmission function situation of change of 4m.
Figure 10 b is an imaging system application example when asymmetric broad sense cube encodes, when relative rotation angle is 5 °,
Image-forming range is the corresponding transmission function situation of change of 10m.
Figure 10 c is an imaging system application example when asymmetric broad sense cube encodes, when relative rotation angle is 5 °,
Image-forming range is the corresponding transmission function situation of change in infinity.
Figure 11 a is an imaging system application example when asymmetric broad sense cube encodes, when relative rotation angle is 8 °,
Image-forming range is the corresponding transmission function situation of change of 4m.
Figure 11 b is an imaging system application example when asymmetric broad sense cube encodes, when relative rotation angle is 8 °,
Image-forming range is the corresponding transmission function situation of change of 10m.
Figure 11 c is an imaging system application example when asymmetric broad sense cube encodes, when relative rotation angle is 8 °,
Image-forming range is the corresponding transmission function situation of change in infinity.
Appended drawing reference is as follows:
1- target, 2- imaging lens, 3- phase mask component, 4- image detector, 5- image processing unit, 6- image.
Specific embodiment
The utility model proposes a kind of adjustable wavefront coded imaging systems of phase mask.
With reference to Fig. 1, the system include the imaging lens 2 set gradually along optical axis transmission direction, phase mask component 3,
Image detector 4 and image processing unit 5；
The phase mask component by two three times rectangular phase-plate be formed by stacking along optical axis transmission direction, and two three
Secondary rectangular phase-plate can form relative rotation angle using two ways；
Rectangular phase-plate is fixed three times for mode one: one, another three times rectangular phase-plate around optical axis rotation；
Mode two: two three times rectangular phase-plate around optical axis rotation, and two rectangular phase-plate rotation position is not three times
Together；(two three times rectangular phase-plate relative rotation angle can by motor driven one of them rectangular phase-plate rotates three times,
One fixed, and the mode that difference engine can also be used drives)；
In the system that the utility model is proposed, after target 1 is by imaging lens 2 and combined type phase mask component 3,
Fuzzy intermediary image is formed on image detector 4, then image processing unit 5 carries out deconvolution processing, finally obtains focusing
Clearly image 6.
The phase mask that the utility model is proposed is adjustable wavefront coded imaging systems and traditional wavefront coded imaging systems
Maximum difference be: traditional Wavefront Coding system is mostly static application, can not change encoding state once design typification,
No matter the image-forming range of target to be imaged whether exceed the field depth of primal system all must by restore filtering eliminate it is intermediate
Image obscures, and thus influence of the bring noise amplification to picture quality is inevitable.This does not surpass image-forming range also
Out for the target of primal system field depth, a discount actually is beaten to its image quality, at this point, What You See Is What You Get
Direct imaging should be preferred；And the adjustable imaging system of phase code is due to that in no exposure mask conventional imaging and can have exposure mask coding
It is switched between imaging, so exceeding for image-forming range and can well beyond the target of primal system field depth
Prime information is gone back to the maximum extent by wavefront coding technology.This flexibility is that Most current wavefront coded imaging systems do not have
Standby.Therefore, at the image in as shown in figure 1, the phase mask that the utility model is proposed is adjustable wavefront coded imaging systems
Reason unit 5 implements deconvolution processing just for the intermediate code blurred picture obtained under effective exposure mask state.
The key that the adjustable wavefront coded imaging systems of the phase mask that the utility model is proposed are implemented is combined type
Two parts in detachable phase-plate generate controlled relative rotation.Specifically phase mask functional form are as follows:
Q (x, y)=f1(x,y)+f2(x,y)；
Wherein, f1(x, y)=α x3+αy3；
f2(x, y)=α (xcos θ+ysin θ)3+α(ycosθ-xsinθ)3；
In formula, α is the parameter of phase distribution function, and θ represents rectangular phase-plate f three times2Relative to rectangular phase-plate f three times1
Rotation angle and θ value range be [0,360 °], x, y be normalization aperture plane coordinate, wherein x, the value range of y are equal
For [- 1,1]；
Under the premise of α is selected, different rotation angle, θs will make phase mask function Q that classical cube exposure mask, no be presented
There are exposure mask, only cube exposure mask and only cube exposure mask and asymmetric broad sense cube exposure mask in the y-direction in the x-direction,
To realize the conventional switching without between coded imaging and the imaging of effective exposure mask respectively；Effective exposure mask imaging includes classics three
Secondary square coded imaging, only in the x-direction coded imaging, only in the y-direction coded imaging and atypical broad sense cube coding
Imaging.
According to the two-dimensional phase function representation of above-mentioned combined type phase mask component Q, system can be clearly provided several
Switching between kind exposure mask state, as described below:
(1) when rotating angle is 0 ° (360 °), phase mask mode is classical square three times, and phase mask function is 2
αx3+2αy3。
(2) when rotating angle is 180 °, the phase mask that two parts in phase mask component introduce mutually is supported
Disappear, it is conventional imaging systems that Wavefront Coding system, which is degenerated,.
(3) when rotating angle is 90 °, phase mask acts only on a direction, and phase mask function is 2 α y3。
(4) when rotating angle is 270 °, phase mask acts only on a direction, and phase mask function is 2 α x3。
(5) when rotation angle rotates in addition to 0 °, 45 °, 90 °, 135 °, 180 °, 225 °, 270 °, 315 ° and 360 °
Other angles when, phase mask mode be asymmetric broad sense square, phase mask function are three times
(1+cos3θ)αx3+(1+cos3θ)αy3
(-sin3θ)αx3+(sin3θ)αy3
+3αx2y(cos2θsinθ-cosθsin2θ)
+3αxy2(cosθsin2θ+cos2θsinθ)
As shown in Fig. 2 a- Fig. 2 d, composite phase plates Q is given with rotation angle, θ and changes its corresponding phase mask change
The case where change.Fig. 2 a corresponds to α=30, θ=0 °；Fig. 2 b corresponds to α=30, θ=180 °；Fig. 2 c correspond to α=30, θ=
90°；Fig. 2 d corresponds to α=30, θ=270 °.
By Fig. 2 a- Fig. 2 d it is found that when rotating angle is 0 °, 90 °, 180 ° and 270 ° of these special angles, phase
Exposure mask will be undergone without exposure mask, classical cube exposure mask and only along several states such as the direction x or y exposure masks.Wherein, no exposure mask is corresponding
In conventional imaging, Wavefront Coding system at this time will degenerate for conventional imaging systems, be mainly used in the imaging of target to be imaged
Situation of the distance still in field depth.Classical cube exposure mask is then used to inhibit defocus, it is intended to solve serious and severe from
Information caused by coke loses problem.And the coding along the direction x y is not only able to realize target a direction feature in encoding domain
Reinforcement, and realizing that the direction of coding still has the ability of field depth extending.Under these three exposure mask modes, equivalent phase
Position mask parameters numerical value is 2 α.
As shown in Fig. 3 a- Fig. 3 d, any rotation angle given in addition to 0 °, 90 °, 180 ° and 270 ° is corresponding
The two-dimensional phase of asymmetric broad sense cube phase mask is distributed signal.It can be seen that the odd symmetry phase point with Fig. 2 a classics
Cloth is compared, and in Fig. 3, no matter rotates angle is taken as how being worth, phase distribution all loses stringent odd symmetry characteristic.At this point, waiting
Valence is in classical cube coded system (α x3+αy3) in introduce additional, modulate intensity again and be total to by relative rotation angle and α
With the phase-modulation determined.It (is rotated counterclockwise in first quartile or in fourth quadrant up time when rotating angle, θ and taking lesser value
Needle rotation), α sin3θ will very small (general | θ | < 10 °), first two of asymmetric broad sense cube encoding phase function at this time
2 α x will be just approximately equal to3+2αy3, then two phase-modulation intensity is only the part of 2 α, will not pass letter to coding and produce
Raw violent influence is mainly used for adjusting coding transmission function in the MTF of high-frequency location.
Fig. 4 a- Figure 11 c gives in specific optical design example the case where using the utility model.The corresponding light of the example
Learn system parameter are as follows: focal length 35mm, F number 3.5,24 ° of field angle.
Firstly, the system just will be without coding conventional imaging and classics when relative rotation angle is respectively 0 ° and 180 °
It is switched between cube coded imaging.Fig. 4 a- Fig. 4 c and Fig. 5 a- Fig. 5 c is provided respectively without coding conventional imaging and classics
The case where MTF under cube coded imaging two states changes with image-forming range and is changed.It is clear that when system is in normal
When advising image formation state, MTF is more sensitive for the variation of image-forming range, and when system is switched to coded imaging (α=0.005mm)
When, defocus sensibility greatly reduces.
Secondly, the system is converted to only in the x-direction or only along the side y when relative rotation angle is respectively 90 ° and 270 °
It is encoded to implementation.As shown in Fig. 6 a- Fig. 6 c and Fig. 7 a- Fig. 7 c.According to the situation of change for passing letter it is found that target image edge at this time
X or y direction character such as edge will thicken, and the feature in another direction remains unchanged, and thus illustrates that phase is covered at this time
Membrane module can play the role of strengthening special characteristic.This characteristic can be used for realizing the preliminary of variety classes target in encoding domain
Identify classification, as figures 8 a and 8 b show, the edge feature of different directions has obtained apparent change.
Finally, when relative rotation angle has removed except 0 °, 90 °, 180 °, 270 ° and 360 ° several special angles, it is multiple
A kind of form of asymmetrical broad sense cube coding will be presented in box-like phase mask component.As previously mentioned, corresponding to it
In two-dimensional phase function expression, when relative rotation angle is less than 10 °, equivalent phase-modulation is the classics of 2 α of modulate intensity
Rectangular coding adds an asymmetrical coded modulation three times.Since set relative rotation angle is smaller, so at this time
Phase-modulation will primarily serve the purpose for adjusting coding transmission function defocus stability and high frequency mtf value, to allow pair
The signal-to-noise ratio of restored image carries out certain control.As shown in Fig. 9 a~Fig. 9 c, 10a~Figure 10 c and 11a~Figure 11 c, respectively
Give the biography letter situation of change that relative rotation angle takes 2 °, 5 ° and 8 °.By Fig. 9 a~Fig. 9 c, 10a~Figure 10 c and 11a
~Figure 11 c and Fig. 5 a- Fig. 5 c compares respectively it is found that when asymmetric broad sense cube coding, when image-forming range changes
When change, system modulation transmission function still has the characteristics that defocus is insensitive, but at this time between the MTF in the direction x and the direction y
Similarity will appear a degree of variation, at the same time, numerical value and similarity degree of the corresponding MTF at high frequency
Also it will appear certain variation.When needing compared with high s/n ratio imaging, the medium-high frequency numerical value needs for encoding MTF are larger, at this time
The depth of field will be sacrificed and expand range；And when needing the biggish depth of field to expand range, it is necessary to force down MTF entirety numerical value but keep compared with
High consistency.
To sum up, the NEW TYPE OF COMPOSITE phase-plate that the utility model is proposed and the wavefront coded imaging system using the phase-plate
System has the adjustable ability of phase mask mode, and is achieved in and is switching without coding conventional imaging with a variety of coded imaging modes
Purpose, greatly strengthen the application flexibility of Wavefront Coding system.
Claims (7)
1. a kind of adjustable wavefront coded imaging systems of phase mask, including the imaging lens set gradually along optical axis transmission direction
Head, phase mask component, image detector and image processing unit；
It is characterized by:
The phase mask component by two three times rectangular phase-plate be formed by stacking along optical axis transmission direction, and two cube
Shape phase-plate can form relative rotation angle using two ways；
Rectangular phase-plate is fixed three times for mode one: one, another three times rectangular phase-plate around optical axis rotation；
Mode two: two three times rectangular phase-plate around optical axis rotation, and two three times rectangular phase-plate rotation position it is different；
Phase mask functional form are as follows:
Q (x, y)=f1(x,y)+f2(x,y)；
Wherein, f1(x, y)=α x3+αy3；
f2(x, y)=α (xcos θ+ysin θ)3+α(ycosθ-xsinθ)3；
In formula, α is the parameter of phase distribution function, and θ represents rectangular phase-plate f three times2Relative to rectangular phase-plate f three times1Rotation
The value range of gyration and θ are [0,360 °], and x, y are normalization aperture plane coordinate, wherein x, the value range of y be [-
1,1]；
Under the premise of α is selected, different rotation angle, θs will make phase mask function Q that classical cube exposure mask be presented, be not present
Exposure mask, only cube exposure mask and only cube exposure mask and asymmetric broad sense cube exposure mask in the y-direction in the x-direction, thus
The target realized the conventional switching without between coded imaging and the imaging of effective exposure mask respectively, allow to strengthen as needed the direction x or y
Feature, permission system are expanded between scale and restored image signal-to-noise ratio in the depth of field and are selected；Effective exposure mask imaging packet
Include classical square coded imaging three times, only coded imaging, only coded imaging and atypical broad sense three in the y-direction in the x-direction
Power coded imaging.
2. the adjustable wavefront coded imaging systems of phase mask according to claim 1, it is characterised in that: described classical three
The classical square coded imaging three times that power exposure mask reaches, phase mask function are 2 α x3+2αy3, relative rotation angle θ at this time
It is 0 ° or 360 °.
3. the adjustable wavefront coded imaging systems of phase mask according to claim 1, it is characterised in that: described to be not present
Exposure mask reaches conventional without coded imaging, and the phase masks that two parts in phase mask component introduce are cancelled out each other, at this time
Relative rotation angle θ is 180 °.
4. the adjustable wavefront coded imaging systems of phase mask according to claim 1, it is characterised in that: described only along x
The only coded imaging in the x-direction that direction cube exposure mask reaches, phase mask function are 2 α x3, at this time relative rotation angle θ be
270°。
5. the adjustable wavefront coded imaging systems of phase mask according to claim 1, it is characterised in that: described only along y
The only coded imaging in the y-direction that direction cube exposure mask reaches, phase mask function are 2 α y3, at this time relative rotation angle θ be
90°。
6. the adjustable wavefront coded imaging systems of phase mask according to claim 1, it is characterised in that: described asymmetric
Atypical broad sense cube coded imaging that broad sense cube exposure mask reaches, phase mask function are as follows:
(1+cos3θ)αx3+(1+cos3θ)αy3
(-sin3θ)αx3+(sin3θ)αy3
+3αx2y(cos2θsinθ-cosθsin2θ)
+3αxy2(cosθsin2θ+cos2θsinθ)；
Relative rotation angle θ is its in addition to 0 °, 45 °, 90 °, 135 °, 180 °, 225 °, 270 °, 315 ° and 360 ° at this time
His angle.
7. the adjustable wavefront coded imaging systems of phase mask according to claim 1, it is characterised in that: two cube
The relative rotation angle θ of shape phase-plate is driven by motor driven or using difference engine.
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108761779A (en) * | 2018-05-31 | 2018-11-06 | 西安电子科技大学 | Wavefront coding imaging system with adjustable phase mask |
| US10795168B2 (en) | 2017-08-31 | 2020-10-06 | Metalenz, Inc. | Transmissive metasurface lens integration |
| US11906698B2 (en) | 2017-05-24 | 2024-02-20 | The Trustees Of Columbia University In The City Of New York | Broadband achromatic flat optical components by dispersion-engineered dielectric metasurfaces |
| US11927769B2 (en) | 2022-03-31 | 2024-03-12 | Metalenz, Inc. | Polarization sorting metasurface microlens array device |
| US11978752B2 (en) | 2019-07-26 | 2024-05-07 | Metalenz, Inc. | Aperture-metasurface and hybrid refractive-metasurface imaging systems |
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2018
- 2018-05-31 CN CN201820836746.XU patent/CN208270846U/en not_active Withdrawn - After Issue
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US11906698B2 (en) | 2017-05-24 | 2024-02-20 | The Trustees Of Columbia University In The City Of New York | Broadband achromatic flat optical components by dispersion-engineered dielectric metasurfaces |
| US10795168B2 (en) | 2017-08-31 | 2020-10-06 | Metalenz, Inc. | Transmissive metasurface lens integration |
| US11579456B2 (en) | 2017-08-31 | 2023-02-14 | Metalenz, Inc. | Transmissive metasurface lens integration |
| US11988844B2 (en) | 2017-08-31 | 2024-05-21 | Metalenz, Inc. | Transmissive metasurface lens integration |
| CN108761779A (en) * | 2018-05-31 | 2018-11-06 | 西安电子科技大学 | Wavefront coding imaging system with adjustable phase mask |
| CN108761779B (en) * | 2018-05-31 | 2024-04-05 | 西安电子科技大学 | Wavefront coding imaging system with adjustable phase mask |
| US11978752B2 (en) | 2019-07-26 | 2024-05-07 | Metalenz, Inc. | Aperture-metasurface and hybrid refractive-metasurface imaging systems |
| US11927769B2 (en) | 2022-03-31 | 2024-03-12 | Metalenz, Inc. | Polarization sorting metasurface microlens array device |
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