Holographic optical element preparation device and method for detecting any vector vortex beam
By loading phase holograms of simulated microlens arrays with different exposures onto holographic optical elements, the problem of complex and time-consuming detection of vector vortex beams in existing technologies is solved, achieving the effect of simplifying the device and reducing errors.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-19
- Publication Date
- 2026-03-13
AI Technical Summary
Existing methods for detecting vector vortex beams require two steps, resulting in complex equipment, long processing times, and increased errors.
Two beams of coherent light are used as signal light and reference light, respectively. The polarization state of the optical path is modulated by polarizers and waveplates. A simulated microlens array phase hologram with multiple exposures is loaded onto the holographic optical element to realize the single-step detection of arbitrary vector vortex beams.
The detection device was simplified, the detection time was shortened, and the detection error was reduced.
Smart Images
Figure CN121657403A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of optical technology, specifically to a holographic optical element fabrication device and method for detecting arbitrary vector vortex beams. Background Technology
[0002] Vector vortex beams are a novel type of structured light field that possesses both a spiral phase wavefront and a vortex-distributed polarization state in the cross-section of the light field.
[0003] Currently, methods for detecting vector vortex beams require two steps, each involving the detection of the helical phase wavefront and the polarization state of the vortex distribution. This two-step detection method has the following drawbacks: 1. Complex detection equipment. 2. Long detection time. 3. Increased detection error. Summary of the Invention
[0004] In view of the above problems, this application provides a holographic optical element fabrication apparatus and method for detecting arbitrary vector vortex beams. The method first fabricates a holographic optical element through multiple exposures. After any vector vortex beam to be detected is incident on the fabricated holographic optical element at a specific angle, key information for reconstructing the vector vortex beam can be obtained in the detector, thus recovering the vector vortex beam to be detected. This method avoids the problem of requiring two steps in traditional detection methods and solves the problems of complex detection devices and long detection times in existing vector vortex beam detection methods.
[0005] To achieve the above objectives, the inventors provide a holographic optical element fabrication apparatus for detecting arbitrary vector vortex beams, comprising:
[0006] A signal optical path, wherein the signal optical path is used to transmit signal light; the signal optical path includes:
[0007] A spatial light modulator is disposed on the signal light path. The spatial light modulator is used to load several different phase holograms of analog microlens arrays onto the signal light. The different phase holograms cause the focal point of the reconstructed light to separate in the spatial plane position while the focal length remains unchanged.
[0008] The first polarizer, the first quarter-wave plate, and the first half-wave plate are used to modulate the polarization state of the signal light after it has been loaded with a phase hologram.
[0009] A reference optical path, wherein the reference optical path is used to transmit reference light, and the reference light and the signal light are coherent light, the reference optical path comprising:
[0010] The second polarizer, the second quarter-wave plate, and the second half-wave plate are used to modulate the polarization state of the reference light.
[0011] A holographic optical element is disposed at the position where the signal optical path and the reference optical path interfere.
[0012] In some embodiments, the signal optical path further includes:
[0013] A first lens and a second lens are disposed between the spatial light modulator and the holographic optical element. The optical path from the first lens to the surface of the spatial light modulator is the focal length of the first lens. The distance from the first lens to the second lens is the sum of the focal lengths of the first lens and the second lens. The optical path from the second lens to the surface of the holographic optical element is the focal length of the second lens.
[0014] In some embodiments, the spatial light modulator is a reflective spatial light modulator or a transmissive spatial light modulator.
[0015] In some embodiments, it also includes:
[0016] A first shutter is disposed on the signal optical path and is used to control the opening and closing of the signal optical path;
[0017] A second shutter is disposed on the reference optical path and is used to control the opening and closing of the reference optical path.
[0018] In some embodiments, the reference light and the signal light coincide at the exposure position of the holographic optical element, or the reference light covers the signal light at the exposure position of the holographic optical element.
[0019] In some embodiments, it also includes:
[0020] A detection camera is used to receive the light beam reproduced by the holographic optical element, and the distance between the receiving surface of the detection camera and the holographic optical element is the focal length of the simulated microlens array.
[0021] Another technical solution is also provided: a method for fabricating a holographic optical element for detecting arbitrary vector vortex beams, wherein the method is applied to the holographic optical element fabrication apparatus for detecting arbitrary vector vortex beams as described above, and the method includes the following steps:
[0022] The polarization state of the signal optical path is modulated to a first specific polarization state, and the polarization state of the reference optical path is modulated to a second specific polarization state;
[0023] The spatial light modulator uploads a phase hologram of the first analog microlens array;
[0024] Simultaneously, the signal light and reference light are activated to expose the holographic optical element at the exposure position. After the preset exposure time, the signal light and reference light are turned off.
[0025] The polarization state of the signal optical path is modulated to a third specific polarization state, and the reference optical path is modulated to a fourth specific polarization state;
[0026] A phase hologram of a second analog microlens array is uploaded to the spatial light modulator;
[0027] Then, the signal light and reference light are simultaneously activated to expose the holographic optical element at the exposure position. After the preset exposure time, the signal light and reference light are turned off.
[0028] In some embodiments, the first specific polarization state is a first ellipsoidal polarization state, and the first ellipsoidal polarization state is... θ is the interference angle between the signal light and the reference light in the holographic optical element;
[0029] The second specific polarization state is a right-handed circular polarization state;
[0030] The third specific polarization state is the second ellipsoidal polarization state, and the second ellipsoidal polarization state is... ;
[0031] The fourth specific polarization state is a left-handed circular polarization state.
[0032] In some embodiments, the preset time is 1-3 minutes.
[0033] In some embodiments, the following steps are included:
[0034] The signal optical path is started or stopped by the electronically controlled first shutter, and the reference optical path is started or stopped by the electronically controlled second shutter.
[0035] Unlike existing technologies, the above-mentioned technical solution uses two beams of coherent light as the signal light and the reference light, respectively. First, the polarization state of the signal light path is modulated by a first polarizer, a first quarter-wave plate, and a first half-wave plate, and the polarization state of the reference light is modulated by a second polarizer, a second quarter-wave plate, and a second half-wave plate. Then, a spatial modulator loads several different phase holograms of simulated microlens arrays onto the signal light, so that the signal light and the reference light are exposed multiple times on the holographic optical element. This allows the holographic optical element to record multiple phase-modulated holograms under various specific polarization conditions, enabling single-step detection of arbitrary vector vortex beams. Compared with the traditional two-step detection method, this greatly simplifies the detection device, shortens the detection time, and reduces errors during the detection process.
[0036] The above description of the invention is merely an overview of the technical solution of this application. In order to enable those skilled in the art to better understand the technical solution of this application and to implement it based on the description and drawings, and to make the above-mentioned objectives and other objectives, features and advantages of this application easier to understand, the following description is provided in conjunction with the specific embodiments and drawings of this application. Attached Figure Description
[0037] The accompanying drawings are only used to illustrate the principles, implementation methods, applications, features, and effects of specific embodiments of this application and other related content, and should not be considered as limitations on this application.
[0038] In the accompanying drawings of the instruction manual:
[0039] Figure 1 A schematic diagram of a holographic optical element fabrication device for detecting arbitrary vector vortex beams, as described in a specific embodiment;
[0040] Figure 2 This is a schematic diagram of a structure of the holographic phase diagram described in a specific embodiment;
[0041] Figure 3 This is a schematic diagram of another structure of the holographic phase map described in a specific embodiment;
[0042] Figure 4 A schematic diagram of a holographic optical element fabrication device for detecting arbitrary vector vortex beams, as described in a specific embodiment, for detecting vector vortex beams to be tested;
[0043] Figure 5 This is a schematic diagram of a structure for fabricating a holographic optical element for detecting arbitrary vector vortex beams, as described in a specific embodiment.
[0044] The reference numerals used in the above figures are explained as follows:
[0045] Storage module,
[0046] 1. Beam splitter,
[0047] 2. Spatial light modulator,
[0048] 3. First shutter speed,
[0049] 4. First lens,
[0050] 5. Second lens,
[0051] 6. First polarizer,
[0052] 7. First quarter-wave plate,
[0053] 8. First half-wave plate,
[0054] 9. Holographic optical elements,
[0055] 10. Second shutter speed
[0056] 11. Second polarizer,
[0057] 12. Second quarter-wave plate,
[0058] 13. Second half-wave plate,
[0059] 14. Detection camera. Detailed Implementation
[0060] To illustrate the possible application scenarios, technical principles, implementable specific solutions, and achievable objectives and effects of this application in detail, the following description, in conjunction with the listed specific embodiments and accompanying drawings, provides a detailed explanation. The embodiments described herein are merely illustrative of the technical solutions of this application and are therefore intended to limit the scope of protection of this application.
[0061] In this document, the term "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The term "embodiment" appearing in various places throughout the specification does not necessarily refer to the same embodiment, nor does it specifically limit its independence or connection with other embodiments. In principle, in this application, as long as there are no technical contradictions or conflicts, the technical features mentioned in each embodiment can be combined in any way to form corresponding implementable technical solutions.
[0062] Unless otherwise defined, the technical terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the use of related terms herein is merely for the purpose of describing particular embodiments and is not intended to limit this application.
[0063] In the description of this application, the term "and / or" is used to describe the logical relationship between objects, indicating that three relationships can exist. For example, A and / or B means: A exists, B exists, and A and B exist simultaneously. Additionally, the character " / " in this document generally indicates that the preceding and following objects have an "or" logical relationship.
[0064] In this application, terms such as “first” and “second” are used only to distinguish one entity or operation from another, and do not necessarily require or imply any actual quantity, hierarchy or order relationship between these entities or operations.
[0065] Unless otherwise specified, the use of terms such as “comprising,” “including,” “having,” or other similar expressions in this application is intended to cover non-exclusive inclusion, which does not exclude the presence of additional elements in a process, method, or product that includes the stated elements, such that a process, method, or product that includes a list of elements may include not only those defined elements but also other elements not expressly listed, or elements inherent to such a process, method, or product.
[0066] As understood in the Examination Guidelines, in this application, expressions such as "greater than," "less than," and "exceeding" are understood to exclude the stated number; expressions such as "above," "below," and "within" are understood to include the stated number. Furthermore, in the description of the embodiments in this application, "multiple" means two or more (including two), and similar expressions related to "multiple" are also understood in this way, such as "multiple groups" and "multiple times," unless otherwise explicitly specified.
[0067] In the description of the embodiments of this application, the space-related expressions used, such as "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "vertical," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential," indicate the orientation or positional relationship based on the orientation or positional relationship shown in the specific embodiments or drawings. They are only for the purpose of describing the specific embodiments of this application or for the reader's understanding, and do not indicate or imply that the device or component referred to must have a specific position, a specific orientation, or be constructed or operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.
[0068] Unless otherwise expressly specified or limited, the terms "installation," "connection," "linking," "fixing," and "setting," as used in the description of the embodiments of this application, should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral setting; it can be a mechanical connection, an electrical connection, or a communication connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal connection of two components or the interaction between two components. For those skilled in the art to which this application pertains, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.
[0069] Please see Figure 1 This embodiment provides a holographic optical element fabrication apparatus for detecting arbitrary vector vortex beams, comprising:
[0070] A signal optical path, wherein the signal optical path is used to transmit signal light; the signal optical path includes:
[0071] A spatial light modulator is disposed on the signal light path. The spatial light modulator is used to load several different phase holograms of analog microlens arrays onto the signal light. The different phase holograms cause the focal point of the reconstructed light to separate in the spatial plane position while the focal length remains unchanged.
[0072] The first polarizer 6, the first quarter-wave plate 7, and the first half-wave plate 8 are used to modulate the polarization state of the signal light after it has been loaded with a phase hologram.
[0073] A reference optical path, wherein the reference optical path is used to transmit reference light, and the reference light and the signal light are coherent light, the reference optical path comprising:
[0074] The second polarizer 11, the second quarter-wave plate 12, and the second half-wave plate 13 are used to modulate the polarization state of the reference light.
[0075] A holographic optical element 9 is disposed at the position where the signal optical path and the reference optical path interfere. The holographic optical element 9 is made of a polarization-sensitive photosensitive anisotropic material.
[0076] Two coherent beams are used as the signal beam and the reference beam, respectively. The polarization state of the signal beam is first modulated by the first polarizer 6, the first quarter-wave plate 7, and the first half-wave plate 8, and the polarization state of the reference beam is modulated by the second polarizer 11, the second quarter-wave plate 12, and the second half-wave plate 13. Then, the spatial light modulator 2 loads several different phase holograms of simulated microlens arrays onto the signal beam, so that the signal beam and the reference beam are exposed multiple times on the holographic optical element 9. This allows the holographic optical element 9 to record multiple phase-modulated holograms under various specific polarization conditions, enabling single-step detection of arbitrary vector vortex beams. Compared with the traditional two-step detection method, this greatly simplifies the detection device, shortens the detection time, and reduces errors during the detection process.
[0077] In some embodiments, at least two exposures are performed, during which the signal light is loaded as follows during each exposure: Figure 2-3 The phase hologram shown.
[0078] In some embodiments, the signal optical path further includes:
[0079] A first lens 4 and a second lens 5 are disposed between the spatial light modulator and the holographic optical element 9. The optical path from the first lens 4 to the surface of the spatial light modulator is the focal length of the first lens 4. The distance from the first lens 4 to the second lens 5 is the sum of the focal lengths of the first lens 4 and the second lens 5. The optical path from the second lens 5 to the surface of the holographic optical element 9 is the focal length of the second lens 5.
[0080] The spatial light modulator surface, the first lens 4, the second lens 5, and the holographic material constitute a 4f system. That is, the optical path from the spatial light modulator surface to the first lens 4 is the focal length of the lens, the optical path from the first lens 4 to the second lens 5 is the sum of the focal lengths of the first lens 4 and the second lens 5, and the optical path from the second lens 5 to the front surface of the holographic optical element 9 is the focal length of the second lens 5. This system is used to ensure that the phase hologram of the spatial light modulator used to upload the analog microlens array is recorded in the holographic optical element 9.
[0081] In other embodiments, the spatial light modulator is a transmissive spatial light modulator. A spatial light modulator, under active control, can modulate a parameter of a light field through liquid crystal molecules. This can be achieved by modulating the amplitude of the light field, modulating the phase through refractive index, modulating the polarization state through rotation of the polarization plane, or converting incoherent to coherent light, thereby writing certain information into the light wave to achieve the purpose of light wave modulation. Based on the different readout methods, spatial light modulators can be divided into reflective spatial light modulators and transmissive spatial light modulators.
[0082] In some embodiments, it also includes:
[0083] A first shutter 3 is disposed on the signal optical path and is used to control the opening and closing of the signal optical path;
[0084] The second shutter 10 is disposed on the reference optical path and is used to control the opening and closing of the reference optical path.
[0085] The signal light path and the reference light path can be switched on and off by the first shutter 3 and the second shutter 10 respectively, thereby controlling the exposure time of the signal light and the reference light on the holographic optical element 9. The exposure time is 1-3 minutes. After the exposure time is over, the signal light path and the reference light path are turned off.
[0086] In some embodiments, the reference light and the signal light coincide at the exposure position of the holographic optical element 9, or the reference light covers the signal light at the exposure position of the holographic optical element 9.
[0087] In order to ensure that the holographic optical element 9 can completely record the phase hologram on the signal light, the reference light and the signal light coincide at the exposure position of the holographic optical element 9, or the reference light covers the signal light at the exposure position of the holographic optical element 9.
[0088] like Figure 4 As shown, in some embodiments, it also includes:
[0089] A detection camera 14 is used to receive the light beam reproduced by the holographic optical element 9. The distance between the receiving surface of the detection camera 14 and the holographic optical element 9 is the focal length of the simulated microlens array.
[0090] By passing the vector vortex beam to be tested into the exposed holographic optical element 9 through the reference optical path, the holographic optical element 9 will reproduce the beam. The reproduced beam is detected by the detection camera 14. Based on the focal image of the reproduced light obtained by the detection camera 14, the phase wavefront and vortex distribution polarization state of the incident vector beam can be reconstructed, thus realizing the detection.
[0091] In some embodiments, an apparatus for fabricating holographic optical elements for detecting arbitrary vector vortex beams is provided, comprising:
[0092] Exposure recording is performed using two coherent beams of light. Here, the beam passing through the spatial light modulator (2) is defined as the signal light, and the other beam is defined as the reference light.
[0093] Spatial light modulators are used to upload phase holograms of different analog microlens arrays. The difference between the phase holograms of different analog microlens arrays lies in the separation of the focal point of the reconstructed light in the spatial plane while keeping the focal length constant. For example, the hologram can be as follows: Figure 2 and Figure 3 As shown, all configurations employ a microlens array consisting of 10×10 microlenses. In other embodiments, the array can be adjusted according to actual needs, such as 20×20, and the lens focal length can also be adjusted. In this embodiment, the spatial light modulator is a reflective spatial light modulator. After the signal light is split by the beam splitter 1, it is modulated by the spatial light modulator and then reflected back to the beam splitter 1.
[0094] The spatial light modulator surface, the first lens 4, the second lens 5, and the holographic material constitute a 4f system. That is, the optical path from the spatial light modulator surface to the first lens 4 is the focal length of the lens, the optical path from the first lens 4 to the second lens 5 is the sum of the focal lengths of the first lens 4 and the second lens 5, and the optical path from the second lens 5 to the front surface of the holographic optical element 9 is the focal length of the second lens 5. This system is used to ensure that the phase hologram of the spatial light modulator used to upload the analog microlens array is recorded in the holographic optical element 9.
[0095] When recording a hologram, the first shutter 3 and the second shutter 10 open simultaneously for exposure. The first shutter 3 and the second shutter 10 are electrically controlled, allowing for precise setting of the exposure time. In other embodiments, the first shutter 3 and the second shutter 10 may also be mechanical shutters.
[0096] The first polarizer 6, the first quarter-wave plate 7, and the first half-wave plate 8 are used to record the polarization state of the phase hologram of the analog microlens array when the signal light is modulated and uploaded.
[0097] The second polarizer 11, the second quarter-wave plate 12, and the second half-wave plate 13 are used to modulate the polarization state of the reference light;
[0098] The holographic optical element 9 is made by at least two exposures. The holograms are phase holograms of different simulated microlens arrays. One hologram is exposed each time, and the polarization states of the two beams of light are in a specific polarization state during the exposure.
[0099] Preferably, the spatial light modulator can refer to either a reflective spatial light modulator or a transmissive spatial light modulator.
[0100] Preferably, the exposure positions of the two beams in the holographic optical element 9 should satisfy the condition that the reference light and the signal light coincide or that the reference light can completely cover the signal light, so as to ensure that the upload phase in the spatial light modulator can be completely recorded in the holographic optical element 9.
[0101] Preferably, the interference angle between the two beams of light is unlimited.
[0102] Preferably, the holographic optical element 9 should be a photosensitive anisotropic material with polarization sensitivity.
[0103] Please see Figure 5 A method for fabricating a holographic optical element for detecting arbitrary vector vortex beams, the method being applied to the holographic optical element fabrication apparatus for detecting arbitrary vector vortex beams as described above, the method comprising the following steps:
[0104] Step S510: Modulate the polarization state of the signal optical path to a first specific polarization state, and modulate the polarization state of the reference optical path to a second specific polarization state;
[0105] Step S520: The spatial light modulator uploads the phase hologram of the first analog microlens array;
[0106] Step S530: Simultaneously start the signal light and reference light to expose at the exposure position of the holographic optical element. After the preset exposure time, turn off the signal light and reference light.
[0107] Step S540: Modulate the polarization state of the signal optical path to a third specific polarization state, and modulate the reference optical path to a fourth specific polarization state;
[0108] Step S550: The spatial light modulator uploads the phase hologram of the second analog microlens array;
[0109] Step S560: Simultaneously activate the signal light and reference light to expose the holographic optical element at the exposure position. After the preset exposure time, turn off the signal light and reference light.
[0110] The polarization state of the signal optical path is adjusted to a first specific polarization state, and the polarization state of the reference optical path is adjusted to a second specific polarization state; then, the spatial light modulator uploads a phase hologram of a simulated microlens array, where the phase hologram is as follows: Figure 2 As shown; simultaneously, the signal light path and the reference light path are opened for exposure, with a preset exposure time. Upon completion of the exposure, both the signal light path and the reference light path are closed. Then, the polarization state of the signal light path is adjusted to a third specific polarization state, and the polarization state of the reference light path is adjusted to a fourth specific polarization state. The spatial light modulator uploads another phase hologram of a simulated microlens array, as shown in the figure. Figure 3 As shown; simultaneously, the signal light path and the reference light path are opened for exposure, with a preset exposure time of 1-3 minutes. After exposure, the signal light path and the reference light path are closed simultaneously, completing two exposures of the holographic optical element. By shining the vector vortex beam to be tested into the holographic optical element in the same direction as the reference light, the holographic optical element reconstructs the beam. By acquiring the focal image of the reconstructed beam, the spiral phase wavefront and vortex distribution polarization state of the incident vector vortex beam can be reconstructed, realizing the detection of the vector vortex beam. Compared with the traditional two-step detection method, this method greatly simplifies the detection device, shortens the detection time, and reduces errors in the detection process.
[0111] In some embodiments, the first specific polarization state is a first ellipsoidal polarization state, and the first ellipsoidal polarization state is... θ is the interference angle between the signal light and the reference light inside the holographic optical element; the second specific polarization state is a right-handed circular polarization state; the third specific polarization state is a second elliptic polarization state, and the second elliptic polarization state is... The fourth specific polarization state is a left-handed circularly polarized state. Here, s represents the s-polarization state, i is an imaginary number, and p represents the p-polarization state.
[0112] In some embodiments, the following steps are included:
[0113] The signal optical path is started or stopped by the electronically controlled first shutter, and the reference optical path is started or stopped by the electronically controlled second shutter.
[0114] By controlling the opening and closing of the signal and reference optical paths through electronically controlled first and second shutters, precise control of exposure time can be achieved. In other embodiments, a mechanical shutter can also be used, with the first and second shutters manually controlled to activate or deactivate the signal and reference optical paths.
[0115] In some embodiments, a method for fabricating a holographic optical element for detecting arbitrary vector vortex beams is provided, comprising the following steps:
[0116] The polarization state of the signal optical path is adjusted to an elliptic polarization state, where elliptic polarization is... , where θ is the interference angle between the two beams, and the polarization state of the reference light path is adjusted to a right-hand circular polarization state;
[0117] Phase holograms of analog microlens arrays are uploaded to a spatial light modulator, such as... Figure 2 As shown;
[0118] The first and second shutters are opened simultaneously for exposure, with an exposure time of 1 to 3 minutes. After the exposure is complete, the first and second shutters are closed simultaneously.
[0119] The polarization state of the signal optical path is adjusted to another elliptic polarization state, where elliptic polarization is... The polarization state of the reference optical path is adjusted to a left-handed circular polarization state;
[0120] The spatial light modulator uploads another phase hologram of an analog microlens array, such as... Figure 3 As shown;
[0121] The first and second shutters are opened simultaneously for exposure, with an exposure time of 1 to 3 minutes. After the exposure is complete, the first and second shutters are closed simultaneously.
[0122] A vector vortex beam is incident on the holographic optical element in the same direction as the reference beam. The holographic optical element will reproduce the beam. A probe camera is used to detect the reproduced beam, wherein the distance between the receiving surface of the probe camera and the holographic optical element should be the focal length of the uploaded analog microlens.
[0123] The spiral phase wavefront and vortex distribution polarization state of the incident vector vortex beam can be reconstructed from the focal image of the reconstructed beam acquired by the detection camera, enabling the detection of arbitrary vector vortex beams. Compared to the traditional two-step detection method, this greatly simplifies the detection device, shortens the detection time, and reduces errors during the detection process.
[0124] Finally, it should be noted that although the above embodiments have been described in the text and drawings of this application, this should not limit the scope of patent protection of this application. Any technical solutions that are based on the essential concept of this application and utilize the content described in the text and drawings of this application, resulting in equivalent structural or procedural substitutions or modifications, as well as the direct or indirect application of the technical solutions of the above embodiments to other related technical fields, are all included within the scope of patent protection of this application.
Claims
1. A device for fabricating holographic optical elements for detecting arbitrary vector vortex beams, characterized in that, include: A signal optical path, wherein the signal optical path is used to transmit signal light; The signal optical path includes: A spatial light modulator is disposed on the signal light path. The spatial light modulator is used to load several different phase holograms of analog microlens arrays onto the signal light. The different phase holograms cause the focal point of the reconstructed light to separate at the spatial plane position while the focal length remains unchanged. The first polarizer, the first quarter-wave plate, and the first half-wave plate are used to modulate the polarization state of the signal light after it has been loaded with a phase hologram. A reference optical path, wherein the reference optical path is used to transmit reference light, and the reference light and the signal light are coherent light, the reference optical path comprising: The second polarizer, the second quarter-wave plate, and the second half-wave plate are used to modulate the polarization state of the reference light. A holographic optical element is disposed at the position where the signal optical path and the reference optical path interfere.
2. The holographic optical element fabrication apparatus for detecting arbitrary vector vortex beams according to claim 1, characterized in that, The signal optical path also includes: A first lens and a second lens are disposed between the spatial light modulator and the holographic optical element. The optical path from the first lens to the surface of the spatial light modulator is the focal length of the first lens. The distance from the first lens to the second lens is the sum of the focal lengths of the first lens and the second lens. The optical path from the second lens to the surface of the holographic optical element is the focal length of the second lens.
3. The holographic optical element fabrication apparatus for detecting arbitrary vector vortex beams according to claim 1, characterized in that, The spatial light modulator is either a reflective spatial light modulator or a transmissive spatial light modulator.
4. The apparatus for fabricating holographic optical elements for detecting arbitrary vector vortex beams according to claim 1, characterized in that, Also includes: A first shutter is disposed on the signal optical path and is used to control the opening and closing of the signal optical path; A second shutter is disposed on the reference optical path and is used to control the opening and closing of the reference optical path.
5. The apparatus for fabricating holographic optical elements for detecting arbitrary vector vortex beams according to claim 1, characterized in that, The reference light and the signal light coincide at the exposure position of the holographic optical element, or the reference light covers the signal light at the exposure position of the holographic optical element.
6. The apparatus for fabricating holographic optical elements for detecting arbitrary vector vortex beams according to claim 1, characterized in that, Also includes: A detection camera is used to receive the light beam reproduced by the holographic optical element, and the distance between the receiving surface of the detection camera and the holographic optical element is the focal length of the simulated microlens array.
7. A method for fabricating a holographic optical element for detecting arbitrary vector vortex beams, characterized in that, The method is applied to the holographic optical element fabrication apparatus for detecting arbitrary vector vortex beams as described in any one of claims 1-6, and the method includes the following steps: The polarization state of the signal optical path is modulated to a first specific polarization state, and the polarization state of the reference optical path is modulated to a second specific polarization state; The spatial light modulator uploads a phase hologram of the first analog microlens array; Simultaneously, the signal light and reference light are activated to expose the holographic optical element at the exposure position. After the preset exposure time, the signal light and reference light are turned off. The polarization state of the signal optical path is modulated to a third specific polarization state, and the reference optical path is modulated to a fourth specific polarization state; A phase hologram of a second analog microlens array is uploaded to the spatial light modulator; Then, the signal light and reference light are simultaneously activated to expose the holographic optical element at the exposure position. After the preset exposure time, the signal light and reference light are turned off.
8. The method for fabricating a holographic optical element for detecting arbitrary vector vortex beams according to claim 7, characterized in that, The first specific polarization state is the first elliptically polarized state, and the first elliptically polarized state is θ is the interference angle between the signal light and the reference light in the holographic optical element; The second specific polarization state is a right-handed circular polarization state; The third specific polarization state is the second ellipsoidal polarization state, and the second ellipsoidal polarization state is... ; The fourth specific polarization state is a left-handed circular polarization state.
9. The method for fabricating a holographic optical element for detecting arbitrary vector vortex beams according to claim 7, characterized in that, The preset time is 1-3 minutes.
10. The method for fabricating a holographic optical element for detecting arbitrary vector vortex beams according to claim 7, characterized in that, Includes the following steps: The signal optical path is started or stopped by the electronically controlled first shutter, and the reference optical path is started or stopped by the electronically controlled second shutter.