CN214540190U - Splicing processing device for holographic lens - Google Patents
Splicing processing device for holographic lens Download PDFInfo
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- CN214540190U CN214540190U CN202120864279.3U CN202120864279U CN214540190U CN 214540190 U CN214540190 U CN 214540190U CN 202120864279 U CN202120864279 U CN 202120864279U CN 214540190 U CN214540190 U CN 214540190U
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Abstract
The application provides a splicing processing device of holographic lenses. It includes: holographic lens exposure concatenation controlling means and holographic lens base plate adjusting device, this holographic lens exposure concatenation controlling means includes: the first attitude control platform is connected with the first spatial filter, the second attitude control platform is connected with the second spatial filter, the piezoelectric ceramic is connected with the first reflector and used for controlling the micro displacement of the first reflector so as to change the optical path of reflected light in real time, and the parallel flat plate is arranged between the semi-transmitting semi-reflecting mirror and the holographic lens substrate and positioned above the semi-transmitting semi-reflecting mirror and used for deflecting the optical path so that the positions of the first spherical wave and the second spherical wave generate micro displacement to form light field interference fringes which are superposed with the prepared holographic lens to form moire fringes. The device enlarges the aperture of the light beam through deflection of the light beam, splices the curved grating lines through exposure splicing to manufacture a large-aperture holographic lens, and meets the requirements of a large-aperture telescope system.
Description
Technical Field
The application relates to the technical field of information optics, in particular to a splicing processing device for a holographic lens.
Background
With the development of the fields of social economy and national security strategy, the demand for space remote sensing is rapidly increasing. Geosynchronous orbit satellites have high time resolution and continuous detection capability and become an important development direction in the field of remote sensing satellites. The large-aperture telescope imaging system can effectively improve the spatial resolution of the geosynchronous orbit satellite. The increased mirror aperture in conventional mirror imaging systems results in increased mass and volume of the system, beyond the vehicle limits. The splicing technology of a plurality of small-caliber reflecting mirrors needs to accurately control the common phase among the sub-mirrors, and has high requirements on the performance of the wavefront sensor. And diffraction imaging technology [ zhangjian, chinazan, yin-rigor, etc.. a large-caliber thin-film fresnel diffraction element for space telescopes [ J ] optical precision engineering, 2016, 24 (6): the 1289-1296 diffraction primary mirror has the advantages of wide material selection, easy large caliber, small mass, loose surface tolerance and the like, and has great application prospect in the field of space telescope imaging. National wang luoqiu et al [ wang luoqiu. thin film element key technology research based on diffraction imaging system [ D ]. vinpock: the Chinese academy of sciences, 2017, designs a film diffraction telescope system, manufactures a four-step polyimide film primary mirror with the aperture of 320mm, and measures the supporting structure and the imaging performance of the film diffraction mirror; zhanjia et al [ zhanjia, chestnut benamantai, yin rigor, etc.. large-caliber thin-film fresnel diffraction element for space telescope [ J ] optical precision engineering, 2016, 24 (6): 1289-1296] two-step structured Fresnel zone plate with the caliber of 400mm is manufactured on the glass substrate by ultraviolet lithography and ion beam etching, and the manufacturing of the polyimide substrate film zone plate is completed by a replication process, and the measured diffraction efficiency is 34 percent. The manufacturing method of the diffraction primary mirror in the research adopts ultraviolet lithography or laser direct writing, the caliber of an element is limited by the caliber of equipment, and manufacturing errors can be generated in the ultraviolet lithography and the laser direct writing in a region with smaller line width. Numerical simulation of a split-piece telescope [ J ] optics report, 2014,34 (7): 0722002, a theoretical model of the spliced telescope imaging system is established. The mechanical splicing is an effective way for realizing the primary mirror of a telescope with a diameter of 10m or more, the mechanical splicing control relates to the splicing of six dimensions of space, a control system is very complex, real-time monitoring and adjustment are needed, and the telescope is not suitable for being used in space.
There is a need for an improved existing large aperture thin film lens.
SUMMERY OF THE UTILITY MODEL
In order to overcome the above-mentioned defect point, the present application aims at: the splicing processing device of the holographic lens is simple and controllable in manufacturing method and meets the requirement of a large-caliber telescopic system on high spatial resolution.
In order to achieve the purpose, the following technical scheme is adopted in the application:
a splicing processing device for a holographic lens is characterized by comprising:
a holographic lens exposure splicing control device and a holographic lens substrate adjusting device,
the holographic lens exposure splicing control device comprises:
a first attitude console connected to the first spatial filter,
a second attitude console connected to the second spatial filter,
piezoelectric ceramics connected to the first reflector for controlling the micro-displacement of the first reflector to change the optical path of the reflected light in real time, and parallel plates,
the parallel flat plate is arranged between the semi-transparent semi-reflective mirror and the holographic lens substrate and positioned above the semi-transparent semi-reflective mirror and used for deflecting the light path to enable the positions of the first spherical wave and the second spherical wave to generate tiny displacement, so that light field interference fringes are formed and overlapped with the prepared holographic lens, and further moire fringes are formed.
In a preferred embodiment, the holographic lens substrate adjusting apparatus includes: a holographic lens substrate five-dimensional adjusting frame, a rotating frame and a diaphragm,
the diaphragm is arranged in front of the holographic lens substrate,
the holographic lens substrate five-dimensional adjusting frame is connected with the holographic lens substrate and used for adjusting the spatial position of the holographic lens substrate,
the rotating frame is configured to rotate around an optical axis so as to realize multiple splicing exposure, four positioning columns are configured on the side, facing the light beam surface, of the rotating frame, and the four positioning columns are located on the periphery of the rotating frame respectively so as to place the diaphragm during multiple splicing.
Further the diaphragm comprises: a circular sub-grating diaphragm and 4 holographic lens edge sub-grating diaphragms,
the circular sub-grating diaphragm is used for shading light when the circular sub-grating is manufactured,
the holographic lens edge sub-grating diaphragm is used for shading when the first to fourth sub-gratings at the edge of the holographic lens are manufactured. Preferably, the diaphragms are configured into five types, namely a circular sub-grating diaphragm and a first sub-grating diaphragm at the edge of the holographic lens, a second sub-grating diaphragm at the edge of the holographic lens, a third sub-grating diaphragm at the edge of the holographic lens, and a fourth sub-grating diaphragm at the edge of the holographic lens, wherein the circular sub-grating diaphragm is used for shading when the circular sub-grating is manufactured, and the sub-grating diaphragm at the edge of the holographic lens is used for shading when the first to fourth sub-gratings at the edge of the holographic lens are manufactured.
In a preferred embodiment, the adjusting device of the holographic lens substrate is finely adjusted so that the real-time interference light field of the first spherical wave and the second spherical wave is superimposed on the prepared central circular sub-grating of the holographic lens substrate to obtain moire fringes.
In a preferred embodiment, the splicing processing device for the holographic lens is characterized by further comprising a sealing ring, wherein the sealing ring is used for sealing the central circular sub-grating of the holographic lens substrate after the exposure of the edge sub-grating of the holographic lens substrate is completed so as to develop the edge sub-grating.
In a preferred embodiment, the moire fringe monitoring module comprises a camera and an image acquisition and display module, wherein the camera is connected with the image acquisition and display module, and the image acquisition and display module displays the moire fringe image shot by the camera in real time.
In a preferred embodiment, the splicing processing device for the holographic lens is characterized by further comprising a storage module, which is connected with the camera and is used for storing pictures shot by the camera.
Advantageous effects
According to the technical scheme, a splicing idea is used, a circular sub-grating is firstly prepared in the center of a holographic lens substrate, the circular sub-grating is a sub-region of a holographic lens, the relative position of the holographic lens substrate and a real-time interference light field is adjusted, so that the circular sub-grating and the real-time interference light field are partially overlapped to generate moire fringes, the holographic lens substrate is adjusted to enable the moire fringes to be in a zero-fringe state, and the rest sub-gratings on the edge of the holographic lens substrate are sequentially exposed and processed, so that the large-caliber holographic lens is obtained. Compared with the prior art, the splicing processing method of the holographic lens provided by the embodiment of the application is particularly suitable for processing large-aperture gratings with the diameter of more than 400mm, the splicing precision is high, the aperture of the light beam is enlarged through deflection of the light beam, then the curved grating lines are spliced through exposure splicing, the manufacturing process is simple and controllable, and the method can be carried on a geosynchronous orbit satellite and the like to meet the requirement of high spatial resolution of a large-aperture telescope system.
Drawings
FIG. 1 is a spliced exposure light path diagram of a holographic lens according to an embodiment of the present disclosure.
FIG. 2 is a schematic diagram of a holographic lens mosaic according to an embodiment of the present application.
FIG. 3 shows moire fringes formed by the superposition of a circular sub-grating and a real-time interference light field according to an embodiment of the present application.
FIG. 4 shows a measurement optical path of a holographic lens interferometer according to an embodiment of the present application.
Fig. 5 is a diagram illustrating measurement results of a holographic lens according to an embodiment of the present application.
The system comprises a 1-beam splitter prism, a 2-first reflector, a 3-piezoelectric ceramic, a 4-second reflector, a 5-first spatial filter, a 6-second spatial filter, a 7-half-mirror, a 8-first spatial filter attitude control platform, a 9-second spatial filter attitude control platform, a 10-parallel flat plate, an 11-holographic lens substrate, a 12-holographic lens substrate attitude adjusting system and a 13-moire fringe monitoring system.
Detailed Description
The above-described scheme is further illustrated below with reference to specific examples. It should be understood that these examples are for illustrative purposes and are not intended to limit the scope of the present application. The conditions employed in the examples may be further adjusted as determined by the particular manufacturer, and the conditions not specified are typically those used in routine experimentation.
The application provides a splicing processing method of a holographic lens, which comprises the following steps:
exposing a circular sub-grating at the geometric center of the holographic lens substrate;
obtaining a reference stripe based on the inserted parallel plate and recording based on a recording device; deflecting the light beam to enlarge the aperture of the light beam;
and exposing the first sub-grating at the edge of the holographic lens substrate, rotating the first sub-grating for exposure at a preset angle, and sequentially splicing other sub-gratings at the edge of the holographic lens substrate to obtain the large-caliber holographic lens. In this embodiment, 4 sub-gratings are arranged at the edge of the holographic lens substrate and rotated by 90 °, and in other embodiments, 6 sub-gratings are arranged at the edge of the holographic lens substrate and rotated by 60 °, so as to sequentially splice the other sub-gratings at the edge of the holographic lens substrate. In the implementation method, the light path is deflected by using the parallel flat plate, the aperture of the light beam is enlarged due to the deflection of the light beam, and the curved grating lines are sequentially spliced with the edge sub-gratings (such as the first sub-grating to the fourth sub-grating) through rotary exposure, so that the large-aperture holographic lens is obtained. In the present embodiment, 4 sub-gratings (first to fourth sub-gratings) are arranged at the edge of the hologram lens substrate. In other embodiments, the number of edge-disposed sub-gratings is not limited, and the curved grating lines may be spliced by rotary exposure of the holographic lens substrate.
In one embodiment, the method for forming the circular sub-grating is described with reference to fig. 1 and 2, in which a circular sub-grating is first formed at the center of a holographic lens substrate. According to fig. 1, a laser beam emitted from a laser is split into transmitted light and reflected light by a beam splitter prism 1,
the transmitted light enters a first spatial filter 5, after filtering, the transmitted light beam becomes a transmitted first spherical wave, and the transmitted light is projected onto a holographic lens substrate 11 to be exposed through a half-transmitting and half-reflecting mirror 7;
the reflected light is reflected by the first reflecting mirror 2 and the second reflecting mirror 4 and then enters the second spatial filter 6, and after filtering, the reflected light beam is changed into a second emitted spherical wave and enters the half mirror 7 to be reflected and projected on the holographic lens substrate 11 to be exposed. The first spherical wave and the second spherical wave interfere with each other on the hologram lens 11 to form interference fringes of concentric circles. And the center of the interference fringe is coincided with the center of the holographic lens substrate by adjusting the holographic lens substrate adjusting device. And placing the circular sub-grating diaphragm in front of the holographic lens substrate, recording interference fringes of the first and second spherical waves on the holographic lens substrate, developing to obtain the circular sub-grating, resetting the holographic lens substrate (restoring to the original position), and resetting the circular sub-grating diaphragm.
In one embodiment, a circular sub-grating is exposed at the geometric center of the grating substrate, and post-development resetting is also included.
In one embodiment, with continued reference to fig. 1, 2 and 3, exposing the circular sub-grating further comprises: adjusting the relative position of the grating substrate and the real-time interference light field to make the moire fringes of the circular sub-grating and the real-time interference light field be in a zero fringe state (i.e. a black circle fringe-free state), inserting the parallel flat plate 10 into the light path at the moment, moving the parallel flat plate 10 to a half position of the light beam aperture, deflecting the first spherical wave through the parallel flat plate 10, introducing an additional optical path difference, changing the moire fringes into the moire fringes of concentric rings from the zero fringe state, and recording the moire fringes at the moment in real time by using a camera as shown in figure 3 to set the moire fringes as a standard fringe.
In one embodiment, the step of beam deflecting and enlarging the aperture of the beam further comprises: the first reflector 2 is finely adjusted to deflect the reflected light beam towards the edge of the holographic lens substrate, and the moire fringes of the central circular sub-grating of the holographic lens substrate are restored to the standard fringes by adjusting the three-dimensional adjusting frames of the first spatial filter 5 and the second spatial filter 6.
And performing exposure splicing based on the deflection of the light beam and the rotation of the grating substrate to ensure that the Moire fringes of the circular sub-grating and the real-time interference light field are consistent with the previous reference fringes.
In one embodiment, the first sub-grating at the edge of the holographic lens substrate includes:
moire fringes shown in figure 3 are collected in real time, the real-time fringes are compared with standard fringes, phases of the real-time collected fringes and the standard fringes are consistent by adjusting piezoelectric ceramics of a first reflector until exposure of a first sub-grating at the edge of a holographic lens substrate is finished, and a first sub-grating diaphragm at the edge of the holographic lens substrate is closed. And rotating the holographic lens substrate adjusting device to enable the holographic lens substrate to rotate 90 degrees clockwise around the optical axis. And finely adjusting the holographic lens substrate adjusting device to enable the phases of the real-time collected fringes and the standard fringes to be consistent. And opening a second sub-grating diaphragm at the edge of the holographic lens substrate, collecting the moire fringes shown in the attached figure 3 in real time, comparing the real-time fringes with the standard fringes, adjusting the piezoelectric ceramic 3 of the first reflector to enable the phases of the real-time collected fringes and the standard fringes to be consistent until the second sub-grating diaphragm at the edge of the holographic lens substrate is exposed, and closing the second sub-grating diaphragm at the edge of the holographic lens substrate. And sequentially exposing the third sub-grating and the fourth sub-grating at the edge of the holographic lens substrate according to the same method.
In one embodiment, after the exposure of the edge sub-gratings of the holographic lens substrate is completed, the central circular sub-gratings of the holographic lens substrate are sealed by the sealing ring, and the edge sub-gratings are developed. After the development is finished, the holographic lens substrate is placed into a measuring light path of an interferometer, the measuring light path is shown in figure 4, the interferometer emits convergent spherical waves, a convergent point is right at the focus of the holographic lens, the convergent point is changed into divergent spherical waves after passing through the convergent point, the divergent spherical waves are incident on the holographic lens substrate, the-1-order diffraction light of the holographic lens substrate is changed into parallel light, and the parallel light returns to the interferometer along the original light path through an auxiliary reflector. The measurement results are shown in fig. 5, and the splicing error between each piece is better than 0.1 lambda.
The embodiment of the application provides a holographic lens splicing and processing device using the method, and the device comprises:
the device comprises a holographic lens exposure recording device, a holographic lens exposure splicing control device and a holographic lens substrate adjusting device. The apparatus proposed by the present application is described next with reference to the accompanying drawings.
The exposure splicing light path diagram of the holographic lens of the embodiment of the application is shown in figure 1,
a laser beam emitted from the laser is split into transmitted light and reflected light by the beam splitting prism 1,
the transmitted light enters a first spatial filter 5, after filtering, the transmitted light beam becomes a transmitted first spherical wave, and the transmitted light is projected onto a holographic lens substrate 11 to be exposed through a half-transmitting and half-reflecting mirror 7;
the reflected light is reflected by the first reflecting mirror 2 and the second reflecting mirror 4 and then enters the second spatial filter 6, and after filtering, the reflected light beam is changed into a second emitted spherical wave and enters the half mirror 7 to be reflected and projected on the holographic lens substrate 11 to be exposed.
The first spherical wave and the second spherical wave interfere with each other on the hologram lens 11 to form interference fringes of concentric circles.
The holographic lens exposure splicing control device comprises: an attitude control stage 8 of the first spatial filter 5, an attitude control stage 9 of the second spatial filter 6, the piezoelectric ceramics 3, the parallel plate 10, and a moire monitoring system 13.
Wherein the attitude control stages 8 and 9 of the first and second spatial filters 5 and 6 are used to adjust the spatial positions of the first and second spherical waves. The piezoelectric ceramic is used for controlling the micro displacement of the first reflecting mirror 2 and changing the optical path of reflected light in real time. The parallel plate 10 performs deflection of the optical path, so that the positions of the first spherical wave and the second spherical wave are slightly displaced, and the formed light field interference fringes are superposed with the prepared holographic lens to form moire fringes. The moire monitoring system 13 comprises a camera, an image acquisition and display system, displaying in real time the images of the moire fringes. The moire fringe monitoring system also comprises a storage module which is connected with the camera and is used for storing pictures shot by the camera.
The holographic lens substrate adjusting device mainly comprises: the holographic lens comprises a holographic lens substrate five-dimensional adjusting frame, a rotating frame and a diaphragm. The five-dimensional adjusting frame of the holographic lens substrate is used for adjusting the spatial position of the holographic lens substrate, and the rotating frame can rotate around the optical axis to realize multiple splicing exposure.
The above embodiments are merely illustrative of the technical concepts and features of the present application, and the purpose of the embodiments is to enable those skilled in the art to understand the content of the present application and implement the present application, and not to limit the protection scope of the present application. All equivalent changes and modifications made according to the spirit of the present application are intended to be covered by the scope of the present application.
Claims (7)
1. A splicing processing device for a holographic lens is characterized by comprising:
a holographic lens exposure splicing control device and a holographic lens substrate adjusting device,
the holographic lens exposure splicing control device comprises:
a first attitude console connected to the first spatial filter,
a second attitude console connected to the second spatial filter,
a piezoelectric ceramic connected to the first reflecting mirror for controlling the micro-displacement of the first reflecting mirror to change the optical path of the reflected light in real time, an
And the parallel flat plate is arranged between the semi-transparent semi-reflective mirror and the holographic lens substrate and positioned above the semi-transparent semi-reflective mirror and used for deflecting the light path to enable the positions of the first spherical wave and the second spherical wave to generate micro displacement so as to form light field interference fringes which are superposed with the prepared holographic lens and further form moire fringes.
2. The hologram lens splicing processing apparatus according to claim 1,
the hologram lens substrate adjusting apparatus includes: a holographic lens substrate five-dimensional adjusting frame, a rotating frame and a diaphragm,
the diaphragm is arranged in front of the holographic lens substrate,
the holographic lens substrate five-dimensional adjusting frame is connected with the holographic lens substrate and used for adjusting the spatial position of the holographic lens substrate,
the rotating frame is configured to rotate around an optical axis so as to realize multiple splicing exposure, four positioning columns are configured on the side, facing the light beam surface, of the rotating frame, and the four positioning columns are located on the periphery of the rotating frame respectively so as to place the diaphragm during multiple splicing.
3. The hologram lens splicing processing apparatus according to claim 2,
the diaphragm includes: a circular sub-grating diaphragm and 4 holographic lens edge sub-grating diaphragms,
the circular sub-grating diaphragm is used for shading light when the circular sub-grating is manufactured,
the holographic lens edge sub-grating diaphragm is used for shading when the first to fourth sub-gratings at the edge of the holographic lens are manufactured.
4. The hologram lens splicing processing apparatus according to claim 2,
and finely adjusting the holographic lens substrate adjusting device to enable the real-time interference light field of the first spherical wave and the second spherical wave to be superposed with the prepared central circular sub-grating of the holographic lens substrate, so as to obtain moire fringes.
5. The apparatus for splicing and processing a holographic lens according to claim 2, further comprising a sealing ring for sealing the center circular sub-grating of the holographic lens substrate after the exposure of the edge sub-grating of the holographic lens substrate is completed, so as to develop the edge sub-grating.
6. The hologram lens splicing processing apparatus according to claim 1,
the moire fringe monitoring module comprises a camera and an image acquisition and display module, wherein the camera is connected with the image acquisition and display module, and the image acquisition and display module displays an image of moire fringes shot by the camera in real time.
7. The apparatus for splicing and processing holographic lenses according to claim 6, further comprising a storage module connected to the camera for storing the picture taken by the camera.
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| CN202120864279.3U CN214540190U (en) | 2021-04-25 | 2021-04-25 | Splicing processing device for holographic lens |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2022227758A1 (en) * | 2021-04-25 | 2022-11-03 | 苏州大学 | Method and device for splicing and processing holographic lens |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2022227758A1 (en) * | 2021-04-25 | 2022-11-03 | 苏州大学 | Method and device for splicing and processing holographic lens |
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