Special light beam detector preparation device based on holographic technology

Abstract

The utility model relates to a special beam detector preparation device based on holographic technology. The special beam detector preparation device comprises a laser light source; the polarization beam splitter is used for splitting the laser generated by the laser light source into signal light and reference light; the first half wave plate is arranged between the laser light source and the polarization beam splitter; a first quarter-wave plate and a second half-wave plate; the angle regulator is used for emitting the signal light into a polarization sensitive material at different angles; a second quarter-wave plate and a third half-wave plate; and a polarization sensitive material. An existing polarization sensitive material is adopted, the manufacturing process is simple, the cost is low, the problems that in an existing detection method, the size is large, and the manufacturing cost is high can be solved through the material, meanwhile, the device can be manufactured only through exposure, and the machining difficulty is greatly reduced.

Description

Technical Field

[0001] This application relates to the field of polarization holography technology, and specifically relates to a preparation device for a special beam detector based on holography technology. Background Art

[0002] A scalar beam is a beam with a uniform polarization state distribution across the beam cross-section, such as linearly polarized light, circularly polarized light, and elliptically polarized light, etc. A vector beam is a beam with a non-uniform polarization state distribution across the beam cross-section and without a helical phase. A vector vortex beam is a vector beam with a helical phase structure. The polarization state of a vector vortex beam is non-uniformly distributed across the beam cross-section, presenting a form of polarization helix with a certain distribution pattern. It has both a polarization helix and a phase helix.

[0003] Currently, there are various methods to detect special beams such as scalar beams, vector beams, and vector vortex beams. For example, polarization detectors. However, these methods have many limitations, such as complex optical structures, large system volumes, high costs, or complex processing technologies, etc. At the same time, common current polarization detectors can only detect scalar polarized light and cannot detect different polarization distributions in space. While there are some polarization detectors that can detect polarization distributions in space, such as the combination of a quarter-wave plate and a polarizer. However, to measure the polarization distribution through the combination of a quarter-wave plate and a polarizer, the angle of the quarter-wave plate needs to be rotated multiple times to collect the light intensity of the reproduced light. However, this method has complex operation steps and cannot achieve real-time detection, such as in "How to Measure Stokes Polarization Parameters" in [https: / / zhuanlan.zhihu.com / p / 429812820]. At the same time, since the sizes of existing quarter-wave plates and polarizers are usually fixed, such as the size of polarizers on the market is usually one inch or half an inch, the combination of a quarter-wave plate and a polarizer as a polarization detector has the problem of a large volume. And as disclosed in [Literature: J. Dou, T. Xi, C. Ma, J. Di, and J. Zhao, "Measurement of full polarization states with hybrid holography based on geometric phase," Opt. Express 27(6), 7968(2019)], a method of using interference to detect polarization is disclosed. However, in this scheme, an integral device is used, which has problems of complex spatial optical paths and large volume. Summary of the Utility Model

[0004] In view of the above problems, the present application provides a preparation device for a special beam detector based on holographic technology, which solves the problems that the existing combination of a quarter-wave plate and a polarizer as a polarization detector for special beams has complex operation steps and cannot achieve real-time detection, and that the existing detection of polarization by interference has a complex spatial optical path.

[0005] To achieve the above object, the inventor provides a preparation device for a special beam detector based on holographic technology, including:

[0006] A laser light source for generating laser light;

[0007] A polarization beam splitter disposed on the optical path of the laser, for splitting the laser into a signal light and a reference light;

[0008] A first half-wave plate disposed between the laser light source and the polarization beam splitter, for adjusting the intensity ratio between the signal light and the reference light;

[0009] An angle adjuster disposed on the optical path of the signal light, for adjusting the angle at which the signal light enters the polarization-sensitive material;

[0010] A first quarter-wave plate and a second half-wave plate disposed on the optical path of the reference light;

[0011] A second quarter-wave plate and a third half-wave plate disposed on the optical path of the signal light;

[0012] A polarization-sensitive material disposed at the interference of the signal light and the reference light, and the polarization-sensitive material that records the interference field formed by the interference of the signal light and the reference light as a polarization grating is a polarization detector for special beams.

[0013] In some embodiments, it further includes an expanding system disposed between the laser light source and the polarization beam splitter.

[0014] In some embodiments, it further includes a diaphragm disposed between the expanding system and the polarization beam splitter.

[0015] In some embodiments, it further includes a 4f system disposed on the optical path of the signal light.

[0016] In some embodiments, the 4f system includes a first lens and a second lens sequentially disposed on the optical path of the signal light;

[0017] The angle adjuster is disposed on the focusing surface of the first lens;

[0018] The polarization-sensitive material is disposed on the focusing surface of the second lens.

[0019] In some embodiments, a neutral density filter is further included, and the neutral density filter is disposed between the laser light source and the polarization beam splitter.

[0020] In some embodiments, the polarization-sensitive material is one of a photosensitive polymer, a photonic crystal, a polarization-sensitive liquid crystal, and a photosensitive glass.

[0021] In some embodiments, the following are further included:

[0022] A shutter, and the shutter is disposed on the optical path of the signal light;

[0023] A spiral phase plate, and the spiral phase plate is detachably disposed on the optical path of the reference light.

[0024] In some embodiments, the following are further included:

[0025] A first rotation mechanism for changing the fast axis directions of the first quarter-wave plate and the first half-wave plate;

[0026] A second rotation mechanism for changing the fast axis directions of the second quarter-wave plate and the second half-wave plate.

[0027] Different from the prior art, in the above technical solution, laser is generated by a laser light source, and then the laser generated by the laser light source is split into a signal light and a reference light by a polarization beam splitter. The intensity ratio of the signal light and the reference light after being split by the polarization beam splitter is adjusted by a first half-wave plate disposed between the laser light source and the polarization beam splitter. The polarization state of the reference light is adjusted by adjusting the fast axis directions of a first quarter-wave plate and a second half-wave plate on the optical path of the reference light, while the polarization state of the signal light is adjusted by adjusting the fast axis directions of a second quarter-wave plate and a third half-wave plate on the optical path of the signal light. The angle adjuster is adjusted to make the signal light propagate in different directions into the polarization-sensitive material, so that the reference light interferes with the signal light incident into the polarization-sensitive material at different angles, achieving the effect of angle multiplexing. The interference field formed by the signal light and the reference light is recorded as a polarization grating by the polarization-sensitive material, and the polarization-sensitive material recording the polarization grating is used as a polarization detector for special light beams. When detecting the polarization state of the light to be measured, the light to be measured is irradiated into the polarization-sensitive material, and the polarization grating recorded in the polarization-sensitive material can achieve the effect of simultaneous appearance of multiple reproduced light beams, thereby realizing the real-time detection. The prepared polarization-sensitive material is used as a medium for detecting scalar light beams, vector light beams and vector vortex light beams. By using only a dynamic recording device involving ordinary optical elements, multiple specifically involved polarization gratings are recorded into the polarization-sensitive material in an angle multiplexing manner. The polarization-sensitive material recording a specific polarization grating can be used as a device. The existing polarization-sensitive material manufacturing process is simple and low in cost. Using this material can solve the problems of large volume, high preparation cost, complex detection steps and inability to detect in real time in the previous detection methods. At the same time, polarization detection can be realized only by irradiating the light beam to be detected into the polarization-sensitive material, and the spatial optical path is simple. And this device can be prepared only by exposure, greatly reducing the processing difficulty, and this detector can realize the real-time detection.

[0028] The above relevant descriptions of the utility model content are only an overview of the technical solution of this application. In order to enable those of ordinary skill in the art to more clearly understand the technical solution of this application, and then can be implemented according to the content recorded in the text of the specification and the drawings. And in order to make the above objects, other objects, features and advantages of this application more easily understood, the following is described in conjunction with the specific embodiments and drawings of this application. Brief Description of the Drawings

[0029] The drawings are only used to illustrate the principles, implementation methods, applications, features and effects of the specific embodiments of this application and other related contents, and should not be considered as a limitation to this application.

[0030] In the drawings of the specification:

[0031] Figure 1Schematic diagram of a structure of the special beam detector preparation device based on holographic technology described in the specific implementation manner;

[0032] Figure 2 Another schematic diagram of a structure of the special beam detector preparation device based on holographic technology described in the specific implementation manner;

[0033] Figure 3 Another schematic diagram of a structure of the special beam detector preparation device based on holographic technology described in the specific implementation manner;

[0034] Figure 4 Another schematic diagram of a structure of the special beam detector preparation device based on holographic technology described in the specific implementation manner;

[0035] Figure 5 Another schematic diagram of a structure of the special beam detector preparation device based on holographic technology described in the specific implementation manner.

[0036] The descriptions of the reference numerals involved in the above-mentioned drawings are as follows:

[0037] 1. Laser light source,

[0038] 2. Polarizing beam splitter,

[0039] 3. First quarter-wave plate,

[0040] 4. Second half-wave plate,

[0041] 5. Second quarter-wave plate,

[0042] 6. Third half-wave plate,

[0043] 7. Angle regulator,

[0044] 8. First half-wave plate,

[0045] 9. Polarization-sensitive material,

[0046] 10. Beam expander system,

[0047] 11. Aperture,

[0048] 12. Neutral density filter,

[0049] 13. First lens,

[0050] 14. Second lens,

[0051] 15. Shutter,

[0052] 16. Spiral phase plate. Specific implementation manner

[0053] To illustrate in detail the possible application scenarios, technical principles, specific implementable solutions, achievable objectives and effects of this application, the following will be described in detail with reference to the specific examples listed and in conjunction with the accompanying drawings. The embodiments described herein are only used to more clearly illustrate the technical solutions of this application, and thus are only examples and cannot be used to limit the protection scope of this application.

[0054] As used herein, the mention of "embodiment" means that the specific features, structures or characteristics described in connection with the embodiment may be included in at least one embodiment of this application. The term "embodiment" that appears in various positions in the specification does not necessarily refer to the same embodiment, nor does it particularly limit its independence or relevance to other embodiments. In principle, in this application, as long as there is no technical contradiction or conflict, the various technical features mentioned in each embodiment can be combined in any way to form the corresponding implementable technical solution.

[0055] Unless otherwise defined, the meanings of the technical terms used herein are the same as those commonly understood by those skilled in the technical field to which this application belongs; the use of the relevant terms herein is only for describing specific embodiments and is not intended to limit this application.

[0056] In the description of this application, the phrase "and / or" is an expression used to describe the logical relationship between objects, indicating that there can be three relationships. For example, A and / or B means: there is A, there is B, and there is both A and B at the same time. In addition, the character " / " herein generally represents an "or" logical relationship between the associated objects before and after.

[0057] In this application, terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual quantity, primary or secondary, or order relationship between these entities or operations.

[0058] Without more limitations, in this application, the use of the terms "include", "comprise", "have" or other similar expressions in a statement is intended to cover non-exclusive inclusion. These expressions do not exclude the possibility that there may be additional elements in the process, method or product including the said elements, so that a process, method or product including a series of elements may include not only those defined elements, but also other elements not expressly listed, or elements inherent to such process, method or product.

[0059] Similar to the understanding in the "Examination Guidelines", in this application, expressions such as "greater than", "less than", "exceeding" are understood to exclude the corresponding number; expressions such as "above", "below", "within" are understood to include the corresponding number. In addition, in the description of the embodiments of this application, the meaning of "multiple" is two or more (including two), and similar expressions related to "many" are also understood in this way, such as "multiple groups", "multiple times", etc., unless otherwise specifically defined.

[0060] In the description of the embodiments of this application, the spatially related expressions used, such as "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "perpendicular", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., the indicated orientation or positional relationship is based on the orientation or positional relationship shown in the specific embodiment or the drawings, and is only for the convenience of describing the specific embodiments of this application or facilitating the understanding of the reader, rather than indicating or implying that the device or component referred to must have a specific position, a specific orientation, or be constructed or operated in a specific orientation, and thus cannot be understood as a limitation on the embodiments of this application.

[0061] Unless otherwise clearly specified or limited, in the description of the embodiments of this application, the terms such as "installed", "connected", "joined", "fixed", "set" should be understood in a broad sense. For example, the "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 directly connected, or indirectly connected through an intermediate medium; it can be the communication inside two elements or the interaction relationship between two elements. For those skilled in the art to which this application pertains, the specific meanings of the above terms in the embodiments of this application can be understood according to specific circumstances.

[0062] Polarization holography, as a scientific and technological field with broad prospects, can simultaneously detect the Stokes parameters of the light field by using the theory of polarization holography, and thus obtain its amplitude and polarization information. Since the polarization-sensitive material has the property of photoinduced anisotropy, it can be used as the recording material for recording the interference light field information.

[0063] In this application, special beams include, but are not limited to, beams with a non-uniform polarization state distribution on the beam cross-section such as vector beams and vector vortex beams, and also include beams with a uniform polarization state distribution on the beam cross-section such as scalar beams, such as polarized light, circularly polarized light, and elliptically polarized light, and also include vortex beams with linear polarization and circular polarization.

[0064] Specific polarization gratings are such that for different polarization states, after passing through a quarter-wave plate (the fast-axis angle can be arbitrary) and a polarizer, the light intensity and polarization state are regular. By finding a polarization grating, when the above-mentioned polarization state passes through the polarization grating, the light intensity and polarization state of the reproduced light are also regular, and this regularity is the same as the above.

[0065] The polarization state of a special light beam is usually measured by Stokes parameters. Generally speaking, Stokes parameters are a quadruple, which are used to fully describe the polarization state of an optical wave, namely fully polarized light, partially polarized light, and unpolarized light. Fully Polarized Light: It means that the vibration direction of the light remains consistent at all time points. Linear polarized light and circular polarized light both belong to fully polarized light. Partially Polarized Light: It means that the vibration direction of the light remains consistent within a certain time period, but may change in different time periods. Partially polarized light is between fully polarized light and unpolarized light, and its degree of polarization can be quantified by the degree of polarization. Unpolarized Light: For unpolarized light, the vibration direction of the light is random at any time point, that is, the vibration direction of the light is evenly distributed in all directions.

[0066] The four parameters in the Stokes parameters are: S0, S1, S2, and S3.

[0067] This measurement method usually uses a fixed polarizer and a rotating quarter-wave plate. The specific implementation steps are as follows:

[0068] 1. First, fix the transmission axis direction of the polarizer, for example, set it to horizontal.

[0069] 2. Then, place the quarter-wave plate in front of the polarizer and start rotating the quarter-wave plate.

[0070] 3. During the rotation operation, measure the intensity of the light passing through the rotating quarter-wave plate and the fixed polarizer. This process should be performed N rotations, where the value of N should be greater than or equal to 5. According to theoretical inference, when N exceeds 8, no error will occur; while in the range of N values from 5 to 7, it can be regarded as a negligible decimal. To ensure the accuracy of the rotation process, it is necessary to ensure that the rotation angle of the fast axis of the quarter-wave plate remains equally spaced, generally starting from 0 degrees, that is, the rotation angle each time should be 180 degrees / N.

[0071] 4. By changing the rotation angle of the wave plate and recording the corresponding light intensity, a set of data can be obtained, that is, a set of values of the fast axis of different quarter-wave plates and the corresponding transmitted light intensity.

[0072] 5. Through this set of data, the four Stokes parameters of the incident light can be obtained.

[0073] 6. Then, its polarization can be known through the four Stokes parameters.

[0074] The uniqueness of vector light and vector vortex light lies in that their polarization states may vary at different positions on the cross-section of the light beam. To fully describe their polarization properties, it is necessary to measure the polarization state at each point on the cross-section of the light beam. Specifically, for a light beam with a non-uniform polarization distribution in space, the method usually adopted is to measure at each position point on the cross-section of the light beam. First, the light can be passed through a rotating quarter-wave plate, and then this part of the light is passed through a polarizer, and the light intensity is measured at each rotation angle of the quarter-wave plate. It should be noted that these light intensities are distributed in space. Therefore, the polarization states at different positions in space can be detected.

[0075] Light has multiple dimensional information. The focus of this application is to detect the polarization information of light. The detected light includes scalar light beams with the same polarization in space and vector light beams with non-uniform polarization in space. Please refer to Figure 1 For the purpose of detecting the polarization state of special light beams, this embodiment provides a preparation device for a special light beam detector based on holographic technology, including:

[0076] A laser light source 1, which is used to generate laser light;

[0077] A polarization beam splitter 2, which is arranged on the optical path of the laser, and the polarization beam splitter 2 is used to split the laser into signal light and reference light;

[0078] A first half-wave plate 8, which is arranged between the laser light source 1 and the polarization beam splitter 2, and the first half-wave plate 8 is used to adjust the intensity ratio between the signal light and the reference light;

[0079] An angle adjuster 7, which is arranged on the optical path of the signal light, and the angle adjuster 7 is used to adjust the incident angle of the signal light into the polarization-sensitive material;

[0080] A first quarter-wave plate 3 and a second half-wave plate 4, which are arranged on the optical path of the reference light;

[0081] A second quarter-wave plate 5 and a third half-wave plate 6, the second quarter-wave plate 5 and the third half-wave plate 6 being disposed on the optical path of the signal light;

[0082] A polarization-sensitive material 9, the polarization-sensitive material 9 being disposed at the interference of the signal light and the reference light, the polarization-sensitive material 9 being a polarization detector for a special light beam.

[0083] Laser light is generated by a laser light source 1, and then the laser light generated by the laser light source 1 is split into a signal light and a reference light by a polarization beam splitter 2. The intensity ratio of the signal light and the reference light after being split by the polarization beam splitter 2 is adjusted by a first half-wave plate 8 disposed between the laser light source 1 and the polarization beam splitter 2; the polarization state of the reference light is adjusted by adjusting the fast axis directions of a first quarter-wave plate 3 and a second half-wave plate 4 on the optical path of the reference light, and the polarization state of the signal light is adjusted by adjusting the fast axis directions of a second quarter-wave plate 5 and a third half-wave plate 6 on the optical path of the signal light. The angle regulator 7 is adjusted so that the signal light propagates in different directions into the polarization-sensitive material 9, so that the reference light interferes with the signal light incident from different angles into the polarization-sensitive material 9 to achieve the effect of angular multiplexing. The interference field formed by the signal light and the reference light is recorded as a polarization grating by the polarization-sensitive material 9, and the polarization-sensitive material 9 recording the polarization grating is used as a polarization detector for a special light beam, so that when the light to be measured is incident into the polarization-sensitive material 9, multiple reproduced light beams appear simultaneously, realizing the real-time detection. The prepared polarization-sensitive material 9 is used as a medium for detecting scalar light beams, vector light beams and vector vortex light beams. By using only a dynamic recording device involving ordinary optical elements, a plurality of specially involved polarization gratings are recorded into the polarization-sensitive material 9 in an angular multiplexing manner. The polarization-sensitive material 9 recording a specific polarization grating can be used as a device. The existing polarization-sensitive material 9 has a simple manufacturing process and low cost. Using this material can solve the problems of large volume, high preparation cost, complex detection steps and inability to detect in real time in the previous detection methods. At the same time, polarization detection can be realized only by injecting the light beam to be detected into the polarization-sensitive material, and the spatial optical path is simple; and this device can be prepared only by exposure, greatly reducing the processing difficulty, and this detector can realize the real-time detection.

[0084] The detector for measuring the polarization information of a special light beam prepared by the polarization-sensitive material 9 through the special light beam detector preparation device based on holography in the above embodiments has the advantages of small volume, easy implementation, real-time detection and low cost compared with the existing detectors.

[0085] According to the theory of detecting Stokes parameters, it is necessary to record the polarization-sensitive material 9 after at least 5 specific polarization gratings as a polarization detector, integrating the functions of a quarter-wave plate and a polarizer in the polarization-sensitive material 9. When the light to be measured is incident on the polarization-sensitive material 9 with multiple polarization gratings recorded, multiple reproduced light beams will appear, and the light intensities of multiple reproduced light beams can be measured simultaneously, and then the polarization states of the light to be measured in different spaces can be calculated. Compared with the original detection method using a quarter-wave plate and a polarizer, this solution has the following advantages:

[0086] 1. In the original detection method using a quarter-wave plate and a polarizer, when detecting the polarization states of the light to be measured in different spaces, it is necessary to rotate the angle of the quarter-wave plate multiple times to collect the light intensities of the reproduced light beams. However, in this solution, only by injecting the light to be measured into the polarization-sensitive material 9 with multiple polarization gratings recorded, multiple reproduced light beams will appear simultaneously, and only by collecting the light intensities of multiple reproduced light beams at one time, the polarization states of the light to be measured in different spaces can be calculated, realizing the real-time detection.

[0087] 2. In the existing detection method using a quarter-wave plate and a polarizer, the sizes of the quarter-wave plate and the polarizer are usually fixed. For example, the size of the polarizer on the market is usually one inch or half an inch; while using the polarization-sensitive material 9 with multiple polarization gratings recorded by multi-angle multiplexing as a detector, the size of the detector is related to the spot sizes of the signal light and the reference light. Only by adjusting the spot sizes of the signal light and the reference light and then adjusting the size of the polarization grating, the size of the detector can be changed, and a smaller-sized detector can be selected to realize the detection of the polarization state of the light to be measured.

[0088] In this embodiment, in order to facilitate the fast-axis directions of the first quarter-wave plate 3 and the second half-wave plate 4, as well as the fast-axis directions of the second quarter-wave plate 5 and the third half-wave plate 6, it further includes:

[0089] A first rotation mechanism for changing the fast-axis directions of the first quarter-wave plate 3 and the second half-wave plate 4;

[0090] A second rotation mechanism for changing the fast-axis directions of the second quarter-wave plate 5 and the third half-wave plate 6.

[0091] Adjust the fast axis directions of the first quarter-wave plate 3 and the second half-wave plate 4 through the first steering mechanism and adjust the fast axis directions of the second quarter-wave plate 5 and the third half-wave plate 6 through the second steering mechanism to adjust the polarization states of the signal light and the reference light, thereby generating a target polarization grating. During the process of recording the polarization grating, the first quarter-wave plate 3, the second half-wave plate 4, the second quarter-wave plate 5, and the third half-wave plate 6 do not need to rotate. When it is necessary to generate the corresponding target polarization grating, the target polarization grating can be obtained by adjusting the polarization states of the signal light and the reference light. Among them, the rotations of the first quarter-wave plate 3, the second half-wave plate 4, the second quarter-wave plate 5, and the third half-wave plate 6 are all controlled separately, that is, the rotations of the first quarter-wave plate 3, the second half-wave plate 4, the second quarter-wave plate 5, and the third half-wave plate 6 are controlled respectively through four independent rotating platforms.

[0092] Please refer to Figure 2 , in some embodiments, it further includes a beam expander system 10, and the beam expander system 10 is arranged between the laser light source 1 and the polarization beam splitter 2.

[0093] The laser generated by the laser light source 1 can be expanded by the beam expander system 10 to obtain a laser with a larger diameter, and then the signal light and the reference light are obtained by splitting through the polarization beam splitter 2. Among them, the beam expander system 10 can also be obtained by combining a spatial filter and a beam expander lens. The laser generated by the laser light source 1 is filtered by the spatial filter to form a point light source, and then becomes an ideal Gaussian beam after being expanded by the beam expander lens. The purpose of using the beam expander system is to generate spots of the signal light and the reference light with a certain size. Thus, the exposure is completed to form a detector. The size of the detector is related to the spot size. In this embodiment, a flat-top light with uniform light intensity everywhere is required, which can be approximated by an ideal Gaussian beam. However, the light generated by the laser light source is sometimes not an ideal Gaussian light. By using a spatial filter, the beam emitted by the laser light source can be made close to an ideal Gaussian beam. In other embodiments, the beam expander system can also use a telescope to expand the laser generated by the laser light source 1, or the laser light source 1 can directly generate a laser with a larger diameter without expanding through the beam expander system 10. Among them, the flat-top light is a laser beam or electron beam with almost uniform flux (energy density) within a circular area. Generally, it is generated by passing a Gaussian beam through a diffractive optical element.

[0094] Please refer to Figure 2, in some embodiments, it further includes a diaphragm 11, and the diaphragm 11 is disposed between the beam expander system 10 and the polarization beam splitter 2. In order to obtain a laser with a required diameter, after the laser source 1 is expanded by the beam expander system 10, the expanded laser is then restricted by the diaphragm 11 to obtain a laser with the required diameter size, and then the signal light and the reference light are obtained by splitting through the polarization beam splitter 2. By combining the diaphragm with the beam expander system, it is convenient to adjust the spot sizes of the signal light and the reference light, and thus the required size can be obtained.

[0095] In other embodiments, other devices that can adjust the spot sizes of the signal light and the reference light can also be used to replace the beam expander system and the diaphragm.

[0096] Please refer to Figure 3 , in some embodiments, it further includes a neutral density filter 12, and the neutral density filter 12 is disposed between the laser source 1 and the polarization beam splitter 2.

[0097] The light intensities of the signal light and the reference light affect the recording time of the hologram on the polarization-sensitive material 9. By disposing the neutral density filter 12 between the laser source 1 and the polarization beam splitter 2, the light intensity of the laser generated by the laser source 1 can be adjusted.

[0098] In some embodiments, it further includes a 4f system, and the 4f system is disposed on the optical path of the signal light.

[0099] By adding a 4f system composed of a pair of lenses on the optical path of the signal light to improve the quality of the signal light. According to the compensation of the diffraction effect of light by the 4f system, the spot becomes more uniform, and thus the prepared detector has a better effect.

[0100] Please refer to Figures 4 - 5 , in some embodiments, the 4f system disposed on the optical path of the signal light includes a first lens 13 and a second lens 14;

[0101] The angle adjuster 7 is disposed on the focal plane of the first lens 13;

[0102] The polarization-sensitive material 9 is disposed on the focal plane of the second lens 14.

[0103] By disposing the angle adjuster 7 on the focal plane of the first lens 13, only by changing the angle of the angle adjuster 7, the signal light can be sent into the first lens 13. By disposing the polarization-sensitive material 9 on the focal plane of the second lens 14, after the angle adjuster 7 rotates, the signal light can be sent into the polarization-sensitive material 9 at different angles. By using the two lenses of the 4f system, when the incident position of the signal light on the PQ-PMMA remains unchanged, its propagation direction changes.

[0104] In some embodiments, by using the space between the first lens 13 and the second lens 14, the second quarter-wave plate 5 and the third half-wave plate 6 are disposed between the first lens 13 and the second lens 14; in other embodiments, the second quarter-wave plate 5 and the third half-wave plate 6 may also be disposed at other positions on the optical path of the signal light.

[0105] In some embodiments, the polarization-sensitive material 9 is a PQ / PMMA material made of phenanthraquinone (PQ), 2,2-azobisisobutyronitrile (AIBN), and methyl methacrylate (MMA). The PQ / PMMA material made of phenanthraquinone (PQ), 2,2-azobisisobutyronitrile (AIBN), and methyl methacrylate (MMA) has a simple manufacturing process and low cost. In these embodiments, the polarization-sensitive material can also be a photosensitive polymer, a photonic crystal, a polarization-sensitive liquid crystal, a photosensitive glass, a silver halide emulsion, dichromated gelatin, a photopolymer, a photorefractive crystal, etc. Among them, Photosensitive Polymer: A photosensitive polymer is a common holographic material with polarization sensitivity. They can change their internal structure through a light-induced chemical reaction to record the interference pattern of light. Under light illumination, the monomer molecules in the photosensitive polymer will bond into long chains to form a solid polymer, thereby fixing the interference pattern of the light field. Some photosensitive polymers can respond to polarized light and form a polarization-sensitive grating during the polymerization process. Polarization-sensitive photonic crystals: A photonic crystal is a material with a periodic refractive index distribution that can affect the propagation of light passing through it. When preparing a photonic crystal, a polarization-sensitive photonic crystal can be formed by using polarized light, thereby recording a polarization grating. Polarization-sensitive liquid crystals: A polarization-sensitive liquid crystal is an ordered fluid whose molecular arrangement can be controlled by an electric field, a magnetic field, or a light field. This property of the liquid crystal makes it an ideal material for recording a polarization grating. Some liquid crystal materials can respond to polarized light and change their molecular arrangement, thereby recording a polarization grating. Polarization-sensitive photosensitive glass: Some special glass materials, such as borosilicate glass, are sensitive to light and can be modulated by polarized light to generate microstructures, and then form a polarization grating. Preferably, the polarization-sensitive material 9 is a PQ / PMMA material made of phenanthraquinone (PQ), 2,2-azobisisobutyronitrile (AIBN), and methyl methacrylate (MMA), and the PQ / PMMA material is one of the photosensitive polymers. The PQ / PMMA material made of phenanthraquinone (PQ), 2,2-azobisisobutyronitrile (AIBN), and methyl methacrylate (MMA) has a simple manufacturing process and low cost.

[0106] Please refer to Figure 5 , in some embodiments, further comprising:

[0107] a shutter 15, the shutter 15 is disposed on the optical path of the signal light;

[0108] A spiral phase plate 16, the spiral phase plate 16 is detachably disposed on the optical path of the reference light.

[0109] By providing a shutter 15 on the optical path of the signal light and detachably mounting a spiral phase plate 16 on the optical path of the reference light, after a plurality of polarization gratings are recorded on the polarization-sensitive material 9, the optical path of the signal light can be cut off by the shutter 15, and then the reference light is used as the reading light to irradiate the polarization-sensitive material 9, so that the light intensity of the reproduced light of the polarization-sensitive material 9 can be collected, and the polarization-sensitive material 9 can be inspected. Among them, the spiral phase plate 16 generates a vector vortex beam as the vector vortex beam, which is used to verify whether the prepared detector can detect the polarization distribution of the vector vortex beam.

[0110] In some embodiments, a method for detecting a scalar beam / vector beam / vector vortex beam set-one device based on polarization holography is provided. The polarization-sensitive material PQ / PMMA is used as a medium for detecting these beams. A plurality of specially designed polarization gratings are recorded into the polarization-sensitive material PQ / PMMA in an angular multiplexing manner by a dynamic recording device designed only with ordinary optical components. The polarization-sensitive material PQ / PMMA with a specific polarization grating can be used as a device, and by adjusting the beam sizes of the signal light and the reference light, the size of the polarization-sensitive material can be adjusted. This makes it have the advantages of a compact structure, small size, low cost, and short processing time. During the preparation process, only by changing the parameters of some ordinary components can a plurality of target polarization gratings be recorded into the PQ / PMMA. When the scalar beam / vector beam / vector vortex beam to be measured is used as the reading light to irradiate the PQ / PMMA on which a plurality of polarization gratings have been recorded, multiple reproduced lights will be generated. According to the light intensity of the reproduced lights, the detection of three different beams can be realized in one device, greatly reducing the volume and cost of the system and realizing the function of real-time detection.

[0111] To achieve the above objectives, the present application is implemented through the following technical solutions. A preparation device for a scalar beam / vector beam / vector vortex beam detector based on polarization holography includes a polarization-sensitive material PQ / PMMA, quarter-wave plates (including the first quarter-wave plate 3 and the second quarter-wave plate 5), half-wave plates (including the second half-wave plate 4 and the third half-wave plate 6), and a rotation platform with software-controllable rotation speed (including the first steering mechanism and the second steering mechanism). The quarter-wave plates and the half-wave plates are both installed on the rotation platform with software-controllable rotation speed to facilitate controlling the polarization states of the signal light and the reference light. Among them, the first steering mechanism adjusts the fast-axis directions of the first quarter-wave plate and the second half-wave plate by switching the first quarter-wave plate and the second half-wave plate, and the second steering mechanism adjusts the fast-axis directions of the second quarter-wave plate and the third half-wave plate by switching the second quarter-wave plate and the third half-wave plate. The polarization-sensitive material PQ / PMMA with the ability of polarization grating records the specific interference field formed by the signal light and the reference light as a polarization grating. Through the theory of polarization holography, the specific interference field simulates the light field distribution after any polarized light field passes through the quarter-wave plate and the polarizer, and the polarization states of the corresponding signal light and reference light are solved. Preferably, by adding a pair of 4f systems to the signal optical path and rotating the mirror of the signal light, the signal light arrives at the PQ / PMMA at different propagation directions, thereby realizing the recording of multiple polarization gratings in the form of angular multiplexing. Preferably, the polarization-sensitive material 9 is made of phenanthraquinone (PQ), 2,2'-azobisisobutyronitrile (AIBN), and methyl methacrylate (MMA).

[0112] By adopting a dynamic recording device of polarization holography with the polarization-sensitive material PQ / PMMA, polarizer, quarter-wave plate, and half-wave plate, the polarization states of scalar beams / vector beams / vector vortex beams with different polarizations can be flexibly detected. The PQ / PMMA material with a specific polarization grating recorded can be used as a device. Since the manufacturing process of this PQ / PMMA material is simple and the cost is low, the optical device made of this material can solve the problems of large volume and high preparation cost in the previous detection methods, as well as solve the problem of real-time detection. Since the device can be prepared only by exposure, the processing difficulty is greatly reduced.

[0113] Finally, it should be noted that although the above embodiments have been described in the text and drawings of the specification of the present application, the patent protection scope of the present application cannot be limited thereby. Any technical solutions obtained by equivalent structure or equivalent process substitution or modification based on the essential concept of the present application and using the content recorded in the text and drawings of the specification of the present application, as well as those directly or indirectly implementing the technical solutions of the above embodiments in other related technical fields, are all included in the patent protection scope of the present application.

Claims

1. A special beam detector preparation device based on holographic technology, characterized in that: include: A laser light source, the laser light source is used to generate laser light; A polarization beam splitter, which is arranged on the optical path of the laser and is used to split the laser into a signal light and a reference light; A first half-wave plate, the first half-wave plate is arranged between the laser light source and the polarization beam splitter, and the first half-wave plate is used to adjust the intensity ratio between the signal light and the reference light; An angle adjuster, the angle adjuster is arranged on the optical path of the signal light, and the angle adjuster is used to adjust the angle of the signal light entering the polarization sensitive material; A first quarter wave plate and a second half wave plate, wherein the first quarter wave plate and the second half wave plate are arranged on an optical path of the reference light; A second quarter wave plate and a third half wave plate, wherein the second quarter wave plate and the third half wave plate are arranged on the optical path of the signal light; A polarization sensitive material is arranged at the interference point of the signal light and the reference light, and the polarization sensitive material records the interference field formed by the interference of the signal light and the reference light into a polarization grating as a polarization detector of the special light beam.

2. The special beam detector preparation device based on holographic technology according to claim 1 is characterized in that: It also includes a beam expansion system, which is arranged between the laser light source and the polarization beam splitter.

3. The special beam detector preparation device based on holographic technology according to claim 2 is characterized in that: It also includes an aperture, which is arranged between the beam expansion system and the polarization beam splitter.

4. The special beam detector preparation device based on holographic technology according to claim 1 is characterized in that: It also includes a 4f system, which is arranged on the optical path of the signal light.

5. The special light beam detector preparation device based on holographic technology according to claim 4 is characterized in that: The 4f system includes a first lens and a second lens which are sequentially arranged on the optical path of the signal light; The angle adjuster is arranged on the focusing plane of the first lens; The polarization-sensitive material is disposed on a focusing plane of the second lens.

6. The special beam detector preparation device based on holographic technology according to claim 1 is characterized in that: A neutral density filter is also included, and the neutral density filter is arranged between the laser light source and the polarization beam splitter.

7. The special beam detector preparation device based on holographic technology according to claim 1 is characterized in that: The polarization-sensitive material is one of photosensitive polymer, photonic crystal, polarization-sensitive liquid crystal and photosensitive glass.

8. The special beam detector preparation device based on holographic technology according to claim 1 is characterized in that: Also includes: A shutter, the shutter being arranged on the optical path of the signal light; A spiral phase plate is detachably arranged on the optical path of the reference light.

9. The special beam detector preparation device based on holographic technology according to claim 1 is characterized in that: Also includes: A first rotating mechanism, wherein the first rotating mechanism is used to change the fast axis directions of the first quarter wave plate and the second half wave plate; The second rotating mechanism is used to change the fast axis directions of the second quarter wave plate and the third half wave plate.

Images