CN205787191U - A kind of phase coding folding diffraction element - Google Patents
A kind of phase coding folding diffraction element Download PDFInfo
- Publication number
- CN205787191U CN205787191U CN201620511198.4U CN201620511198U CN205787191U CN 205787191 U CN205787191 U CN 205787191U CN 201620511198 U CN201620511198 U CN 201620511198U CN 205787191 U CN205787191 U CN 205787191U
- Authority
- CN
- China
- Prior art keywords
- diffraction element
- folding
- folding diffraction
- phase coding
- lens structure
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Landscapes
- Diffracting Gratings Or Hologram Optical Elements (AREA)
Abstract
The utility model discloses a kind of phase coding folding diffraction element, including folding diffraction element body, described folding diffraction element body is planoconvex lens structure, the plane side of described planoconvex lens structure is coated with broadband photon sieve, described broadband photon sieve is light tight metallic film, described light tight metallic film is provided with the logical light aperture of ring-band shape distribution, and the position distribution of described logical light aperture meets equation.Under same size and focal length, effective operating spectral range more traditional folding diffraction element of folding diffraction element of the present utility model improves about 15 times, can eliminate second order spectrum, it is achieved blur-free imaging in the range of ultra wide bandwidth.
Description
Technical field
This utility model relates to a kind of phase coding folding diffraction element, belongs to optical technical field.
Background technology
2001, Germany L.Kipp professor published an article on Nature periodical, proposed photon sieves first
Concept, after be interpreted into " photon screen ", be a kind of diffraction optics image device, it is little be randomly dispersed on printing opacity annulus
Hole replaces the printing opacity annulus of Fresnel structure to be formed.After structure optimization, the aperture of random distribution can suppress effectively
Secondary and Advanced Diffraction, thus improve contrast and the resolving power of imaging, it might even be possible to the diffraction imaging that breaks traditions is theoretical, it is achieved
Super-resolution imaging.Hereafter, photon screen, by home and abroad scholar's numerous studies, can be widely used in nano-photoetching, astronomical sight
The fields such as survey, Aerial photography, weapon vision.
Photon screen can replace more than the aperture of corresponding zone plate annulus width with diameter, relaxes existing minimum process
The restriction of size, in the case of identical minimum process size, photon screen is capable of higher rate respectively；And on photon screen
The aperture of random distribution, can suppressed sidelobes effect and high order diffraction effectively, improve image quality.
Photon screen is a kind of diffraction optical element, thus sensitive to wavelength change, and common photon screen is not suitable for wide spectrum
Imaging, therefore, develops a kind of new diffraction optical element, solves to there is second order spectrum in prior art, and achromatism bandwidth is little
Problem, it is clear that be a need for.
Summary of the invention
Goal of the invention of the present utility model is to provide a kind of phase coding folding diffraction element, eliminates second order spectrum, it is achieved super
Broadband achromatism blur-free imaging.
To achieve the above object of the invention, the technical solution adopted in the utility model is: a kind of phase coding folding diffraction element,
Including folding diffraction element body, described folding diffraction element body is planoconvex lens structure, the plane one of described planoconvex lens structure
Side is coated with broadband photon sieve, and described broadband photon sieve is light tight metallic film,
Described light tight metallic film is provided with the logical light aperture of ring-band shape distribution, and the position distribution of described logical light aperture is full
Foot equation, in formula, f is tradition light
The focal length of son sieve, n is the annulus sequence number of logical light annulus, and λ is the operation wavelength of photon screen, and R is the radius of broadband photon sieve, and a is
Code coefficient, k is wave number, xm and ym is the center of photon screen m-th aperture, m=1,2,3 num, wherein,,。
Preferably, a=10 π.
Preferably, the focal length of described planoconvex lens structure is 466mm, and bore is 50mm.
Preferably, the substrate of described folding diffraction element is glass material.
Further in technical scheme, the substrate material of described folding diffraction element is BK7 material, at the folding of wavelength 632.8nm
The rate of penetrating is 1.515, and Abbe number is 28.9627.
Preferably, the incident wavelength of described folding diffraction element is 400～700nm.
Principle of the present utility model is as follows: diffraction optical element has the focal length more longer than long wave at short wavelength.But,
The focus condition of refraction optical element is in contrast.Therefore, it can to combine refraction and two kinds of optical elements of diffraction are this contrary
Characteristic is achromatism in some wave-length coverage.On two surfaces that same optical element is contrary, wherein one side processes
Flat raised surface realizes dioptric imaging, and another side processes photon screen and realizes diffraction imaging.If diffraction optical element selects tradition light
Son sieve, two edge wavelength can be designed to focus on same position.But, between centre wavelength and edge wavelength still
There is focus difference (second order spectrum), illustrate that this system yet suffers from the biggest aberration.Spectral region is the widest, this two grades of aberration
The most obvious.
In this utility model: effective Abbe number of diffraction element:
The Abbe number of refractor:
Diffraction element under edge wavelength achromatism and the focal length distribution of refractor:
Wherein,f DOE_2 It is the diffraction element focal length in centre wavelength,f ref_2 It is the refracting telescope focal length in centre wavelength, f
It it is the folding diffraction element focal length in centre wavelength.
Owing to technique scheme is used, this utility model compared with prior art has the advantage that
Under same size and focal length, the more traditional folding of effective operating spectral range of folding diffraction element of the present utility model spreads out
Penetrate element and improve about 15 times, second order spectrum can be eliminated in the range of ultra wide bandwidth, it is achieved blur-free imaging.
Accompanying drawing explanation
Fig. 1 is structural representation of the present utility model.
Fig. 2 is the Experimental equipment of this utility model embodiment one.
Fig. 3 is the achromatism light schematic diagram of tradition folding diffraction element in embodiment one.
Fig. 4 is that in embodiment one, tradition rolls over diffraction element at different wave length along the optical axis surface of intensity distribution.
Fig. 5 is tradition folding diffraction element and point spread function (PSF) figure of phase coding folding diffraction element in embodiment one.
Fig. 6 is that in embodiment one, tradition folding diffraction element and phase coding folding diffraction element MTF at different wavelengths are bent
Line schematic diagram.
Fig. 7 is that in embodiment one, tradition folding diffraction element and phase coding folding diffraction element arrive in wave-length coverage 400nm
The simulation imaging situation comparison diagram of 700nm.
Fig. 8 be in embodiment one tradition folding diffraction element and phase coding folding diffraction element PSF under different bandwidth and
Imaging contrast schemes.
Detailed description of the invention
Below in conjunction with the accompanying drawings and this utility model is further described by embodiment:
Embodiment one: shown in Figure 1, a kind of phase coding folding diffraction element, including folding diffraction element body, roll over diffraction
Component body is planoconvex lens structure, and the plane side of planoconvex lens structure is coated with broadband photon sieve, and broadband photon sieve is for impermeable
Light metallic film,
Light tight metallic film 1 is provided with the logical light aperture of ring-band shape distribution, and the position distribution of logical light aperture meets equation, in formula, f is conventional photonic sieve
Focal length, n is the annulus sequence number of logical light annulus, and λ is the operation wavelength of photon screen, and R is the radius of broadband photon sieve, and a is coding
Coefficient, k is wave number, xm and ym is the center of photon screen m-th aperture, m=1,2,3 num, wherein,,。
Shown in Figure 2, for the Experimental equipment of the present embodiment, wideband light source passes through bandpass filter, a 300nm band
Wide spectrum is combined by long wave pass filter (more than 400nm) and short wave pass filter (less than 700nm), uses Jiao
Carry out away from the CCD that 550mm, the collimator of bore 55mm and Pixel size are 4.54 μm (AVT Prosilica GX2750C)
Imaging test.
In the present embodiment, code coefficient a=10p.
One code coefficient a=10p phase coding folding diffraction element of the present embodiment design, focal length 466mm, diameter 50mm, in
The a length of 632.8nm of cardiac wave, a length of 400nm and 700nm of edge wave, i.e. l1=400nm, l2=632.8nm, l3=700nm.Glass base
BK7 material is selected at the end, and it is 1.515 in the refractive index of wavelength 632.8nm, and Abbe number is 28.9627.
As a comparison, design a traditional hybrid element, by mutually integrated with refracting telescope for conventional photonic sieve, whole
The population parameter of element is focal length 466mm, bore 50mm, l1=400nm, l2=632.8nm, l3=700nm.Substrate of glass is selected
BK7 material (refractive index at wavelength 632.8nm is 1.515, and Abbe number is 28.9627).In centre wavelength 632.8nm, tradition
Photon screen focal length 6864.8nm, refracting telescope focal length 499.954nm.Final design element is at wavelength l1=400nm, l2=632.8nm
It is respectively 464.36nm, 466nm and 464.36nm with the focal length of l3=700nm.Shown in Figure 3, it is clear that at edge wavelength l1
With l3, there is identical focal length value, be achromatic.Shown in Figure 4, for tradition folding diffraction element at different wave length along optical axis
The surface of intensity distribution, it is seen that remain the focus difference of 1.64mm between centre wavelength l2 and edge wavelength l1 and l3, i.e. pass
System folding diffraction element (i.e. bandwidth 300nm) can not reach effective achromatic purpose in 400nm to 700nm wave-length coverage.Pass
The depth of focus of system folding diffraction element is, corresponding wavelength 622.8nm and 642.8nm, i.e. this tradition folding
Effective bandwidth of operation of diffraction element is about 20nm.
Shown in Figure 5, which show tradition folding diffraction element and the point spread function of phase coding folding diffraction element
(PSF) figure.As shown in Fig. 5 (a), tradition folding diffraction element (bandwidth 20nm) in the range of wave-length coverage 622.8nm to 642.8nm
PSF is close to diffraction limit.But when bandwidth is beyond 20nm, PSF becomes disperse, especially edge wavelength 400nm's and 700nm
Time.As shown in Fig. 5 (b), phase coding in the present embodiment folding diffraction element in the range of wavelength 400nm to 700nm, position phase
The PSF of coding folding diffraction element has good concordance.
Shown in Figure 6, for tradition folding diffraction element and phase coding folding diffraction element MTF curve at different wavelengths
Schematic diagram, it can be clearly seen that, when tradition folding diffraction element wavelength departure in centre wavelength 632.8nm time, MTF drastically under
Drop and have zero point to occur, information dropout.But, the MTF of phase coding folding diffraction element is at wave-length coverage 400nm to 700nm model
All there is in enclosing good concordance.Show that phase coding rolls over diffraction element achromatic feasibility in ultra wide band range.
Fig. 7 gives tradition folding diffraction element and phase coding folding diffraction element imitating at wave-length coverage 400nm to 700nm
True imaging contexts comparison diagram.When the incident wavelength of tradition folding diffraction element deviates from centre wavelength 632.8nm, imaging becomes mould
Stick with paste, as shown in (a) in Fig. 7.(b) in Fig. 7, (c) sets forth the middle broad image of phase coding folding diffraction element and right
The restored image answered.It will be seen that the phase coding folding diffraction element in the present embodiment can be at whole visible light wave range 400nm
To 700nm blur-free imaging, have with tradition folding diffraction element in the almost identical resolution of centre wavelength 632.8nm.It is worth note
Meaning, is weighing effective bandwidth of operation, and during image resolution ratio and signal noise ratio (snr) of image, phase coding parameter a can be entered
One-step optimization, thus obtain more suitably bandwidth broadning scope.
Shown in Figure 8, for the PSF under the different bandwidth of tradition folding diffraction element and phase coding folding diffraction element with become
As comparison diagram.First evaluate processing tradition folding diffraction element at bandwidth 28nm and bandwidth 300nm(400nm to 700nm) become
As performance.In Fig. 8, (a), (b) give tradition folding diffraction element PSF under 28nm bandwidth and image, and imaging results is permissible
Accept (in the present embodiment, effective bandwidth of operation of the tradition folding diffraction element of design is 20nm).In Fig. 8, (c), (d) give biography
System rolls over diffraction element PSF under 300nm bandwidth and image, owing to there is second order spectrum under big bandwidth, so finally
Image blur.As a comparison, in Fig. 8, (e), (f) and (g) gives phase coding folding diffraction element at broadband 300nm(400nm
To 700nm) illumination under PSF and imaging results figure.It can be clearly seen that phase coding rolls over diffraction element (a=10p) from figure
Can be with blur-free imaging in 300nm bandwidth, same size and the effectively worked spectral region of focal length are about tradition folding diffraction element
(20nm) about 15 times.
Claims (6)
1. a phase coding folding diffraction element, it is characterised in that: include rolling over diffraction element body, described folding diffraction element body
For planoconvex lens structure, the plane side of described planoconvex lens structure is coated with broadband photon sieve, and described broadband photon sieve is for impermeable
Light metallic film,
Described light tight metallic film is provided with the logical light aperture of ring-band shape distribution, and the position distribution of described logical light aperture meets side
Journey, in formula, f is conventional photonic sieve
Focal length, n is the annulus sequence number of logical light annulus, and λ is the operation wavelength of photon screen, and R is the radius of broadband photon sieve, and a is coding system
Number, k is wave number, xm and ym is the center of photon screen m-th aperture, m=1,2,3 num, wherein,,。
Phase coding the most according to claim 1 folding diffraction element, it is characterised in that: a=10 π.
Phase coding the most according to claim 1 folding diffraction element, it is characterised in that: the focal length of described planoconvex lens structure
For 466mm, bore is 50mm.
Phase coding the most according to claim 1 folding diffraction element, it is characterised in that: the substrate of described folding diffraction element is
Glass material.
5. roll over diffraction element according to the phase coding described in claim 1 or 4, it is characterised in that: the base of described folding diffraction element
Bottom materials is BK7 material, and the refractive index at wavelength 632.8nm is 1.515, and Abbe number is 28.9627.
Phase coding the most according to claim 1 folding diffraction element, it is characterised in that: the incidence wave of described folding diffraction element
A length of 400～700nm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201620511198.4U CN205787191U (en) | 2016-05-30 | 2016-05-30 | A kind of phase coding folding diffraction element |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201620511198.4U CN205787191U (en) | 2016-05-30 | 2016-05-30 | A kind of phase coding folding diffraction element |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN205787191U true CN205787191U (en) | 2016-12-07 |
Family
ID=58138750
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201620511198.4U Expired - Fee Related CN205787191U (en) | 2016-05-30 | 2016-05-30 | A kind of phase coding folding diffraction element |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN205787191U (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107152998A (en) * | 2017-04-20 | 2017-09-12 | 苏州大学 | A kind of photon screen alignment methods based on detection Wavefront Coding system |
| CN109143426A (en) * | 2018-09-19 | 2019-01-04 | 苏州大学 | A kind of phase coding Fresnel Lenses |
| CN109270607A (en) * | 2018-11-30 | 2019-01-25 | 苏州大学 | A kind of one chip broadband achromatism folding spreads out hybrid lens and design method |
| CN110286473A (en) * | 2019-07-23 | 2019-09-27 | 苏州大学 | A kind of one chip achromatism mobile lens |
-
2016
- 2016-05-30 CN CN201620511198.4U patent/CN205787191U/en not_active Expired - Fee Related
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107152998A (en) * | 2017-04-20 | 2017-09-12 | 苏州大学 | A kind of photon screen alignment methods based on detection Wavefront Coding system |
| CN107152998B (en) * | 2017-04-20 | 2019-09-20 | 苏州大学 | A kind of photon screen alignment methods based on detection Wavefront Coding system |
| CN109143426A (en) * | 2018-09-19 | 2019-01-04 | 苏州大学 | A kind of phase coding Fresnel Lenses |
| CN109270607A (en) * | 2018-11-30 | 2019-01-25 | 苏州大学 | A kind of one chip broadband achromatism folding spreads out hybrid lens and design method |
| CN109270607B (en) * | 2018-11-30 | 2020-05-12 | 苏州大学 | Single-chip broadband achromatic refraction and diffraction mixed lens and design method |
| CN110286473A (en) * | 2019-07-23 | 2019-09-27 | 苏州大学 | A kind of one chip achromatism mobile lens |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN205787191U (en) | A kind of phase coding folding diffraction element | |
| JP7328232B2 (en) | Metasurfaces and systems for full-color imaging and methods of imaging | |
| Huang et al. | Design and analysis of extended depth of focus metalenses for achromatic computational imaging | |
| US20020195538A1 (en) | Wavefront coding phase contrast imaging systems | |
| CN105137513B (en) | A kind of broadband photon sieve of phase coding | |
| Banerji et al. | Imaging over an unlimited bandwidth with a single diffractive surface | |
| US11640040B2 (en) | Simultaneous focal length control and achromatic computational imaging with quartic metasurfaces | |
| US20230177655A1 (en) | System and method for digital optical aberration correction and spectral imaging | |
| Teubner et al. | Optical Imaging and Photography: Introduction to Science and Technology of Optics, Sensors and Systems | |
| CN109656006A (en) | A kind of non-focusing all-sky airglow imager of wide spectrum | |
| CN205691846U (en) | A kind of optics athermal, high pixel, low cost thermal imaging system | |
| CN110426762A (en) | A kind of parallel type bionic compound eyes nest area's imaging method and system | |
| CN205003310U (en) | Broadband photon sieve of phase code | |
| CN104297898B (en) | Large-field double-wave harmonic diffractive infrared optical system | |
| CN104865627B (en) | A kind of broadband photon sieve based on wavefront coding technology | |
| Fontbonne et al. | Theoretical and experimental analysis of co-designed binary phase masks for enhancing the depth of field of panchromatic cameras | |
| CN109143426B (en) | Phase coding Fresnel lens | |
| CN209417404U (en) | A kind of non-focusing all-sky airglow imager of wide spectrum | |
| CN204044432U (en) | A kind of refraction-reflection type THz wave imaging device | |
| CN104035197A (en) | Refraction and reflection type THz wave imaging system | |
| CN103852873B (en) | Zoom lens | |
| Strutt | On the diffraction of object-glasses | |
| CN205941963U (en) | Big visual field diffraction photon sieve | |
| Chen et al. | Underwater hyperspectral imaging bioinspired by chromatic blur vision | |
| CN110501768A (en) | A kind of multispectral, big bandwidth photon screen |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20161207 Termination date: 20190530 |
|
| CF01 | Termination of patent right due to non-payment of annual fee |