A standard wave-plate based arbitrary retardation wave-plate generating apparatus and method

Abstract

The application discloses a standard wave plate-based arbitrary retardation wave plate generating device which is composed of a standard wave plate one (1), a fast axis scale dial one (2), a standard wave plate two (3), a fast axis scale dial two (4) and a non-polarization adhesive layer. The device utilizes the characteristics that a birefringence effect is generated after a light beam passes through a wave plate and a polarization phase delay is introduced in different polarization directions, combines two standard wave plates according to different angles to form a combined wave plate, so that different phase delay amounts and fixed fast axis directions are generated after transmitted light passes through the combined wave plate, and the requirement of a wave plate non-standard retardation for optimization of polarization imaging or detection performance is met. Correspondingly, the application also discloses a standard wave plate-based arbitrary retardation wave plate generating method. Compared with a traditional custom non-standard retardation wave plate, the method has the advantages of simplicity, high precision, short period, low cost and applicability to different wavelengths.

Description

Technical Field

[0001] This invention relates to the field of polarization imaging technology, and in particular to an apparatus and method for generating arbitrary delay waveplates based on standard waveplates. Background Technology

[0002] Polarization, as one of the most fundamental optical properties, can reveal physical characteristics that other optical parameters, such as amplitude, frequency, and phase, cannot provide. Polarization imaging combines polarization measurement and imaging techniques, simultaneously acquiring a two-dimensional image of the target and polarization information at each point. While inheriting the advantages of traditional intensity imaging, it can also obtain more dimensional target information, thus finding wide applications in astronomical observation, atmospheric sounding, microscopy, biomedical diagnostics, target detection and identification, remote sensing imaging, and marine monitoring, among other fields.

[0003] Based on different image acquisition methods, polarization imaging techniques can be categorized into time-division, amplitude-division, aperture-division, and focal plane array types. Time-division systems, the most commonly used approach, modulate the polarization state of incident light by adding polarization devices to a traditional imaging system. The Stokes parameters of the incident light are then retrieved from multiple intensity images. This method is simple in structure and data recovery, low-cost, and easy to implement. The detection speed can be increased by the high-speed rotation of a high-precision motor, making it a promising application. Amplitude-division systems offer good real-time performance by dividing the incident light into multiple branches, each with its own independent polarization optical system and detector. However, this method is complex, bulky, and expensive to develop, requiring post-calibration. Aperture-division systems use lens arrays to decompose the optical aperture into different sub-apertures, each becoming an independent branch with its own detector. This method also suffers from complex optical paths and challenging image registration. Focal plane array systems primarily use integrated methods to obtain miniature optical polarization elements. While real-time polarization detection is possible, the array integration process is complex and costly, and inherent pixel-level registration misalignment exists.

[0004] Rotating waveplate imaging is a common time-division polarization imaging technique. Unlike rotating polarizer systems, it modulates polarization by rotating an internal waveplate to ultimately acquire the full Stoke vector of the incident light. Common rotating waveplate systems use a single quarter-waveplate. While its internal components are readily available, it doesn't consider noise immunity. With the introduction of performance metrics such as matrix condition number and EWV, and the development of numerical optimization techniques, single quarter-waveplates have been found to be insufficient for optimal noise immunity. The only waveplate delay that satisfies optimal performance has been determined to be 132°. However, most standard waveplates are designed with quarter-wave or half-wave delays. Although custom delays can now be made to meet specific requirements, such non-standard delayers are not only expensive but also have long manufacturing cycles. The difficulty in obtaining specific delays presents challenges in constructing optimal polarization imaging systems. For obtaining arbitrary delay values ​​using non-custom methods, Li Yanghui et al. proposed a waveplate group design method for compensating arbitrary optical phase delay (CN107102436A, A Waveplate Group Design Method for Compensating Arbitrary Optical Phase Delay). This method utilizes the optical phase difference generated by a waveplate group composed of a quarter-wave plate and a half-wave plate to compensate for arbitrary optical phase delays caused by non-design factors in the system. However, since the quarter-wave plate and half-wave plate are located at the front and rear positions of the optical system, primarily serving to compensate for phase errors and acting as the polarization modulation part of the system, this method is not suitable for polarization imaging systems. Gu Honggang et al. proposed a method and system for detecting the polarization characteristics of a liquid crystal variable phase retarder (CN108534993A, A Method and System for Detecting the Polarization Characteristics of a Liquid Crystal Variable Phase Retarder). Although this method generates arbitrary phase delay values ​​in the liquid crystal through voltage control and obtains the characteristic parameter curves of arbitrary phase delay versus voltage in a single measurement, the liquid crystal is expensive, easily affected by temperature, and the calibration process for voltage and delay values ​​is complex. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention provides an apparatus and method for generating arbitrary delay waveplates based on standard waveplates. The apparatus uses two readily available standard waveplates to generate a high-precision arbitrary polarization delay waveplate. It fully considers the functional relationships between variables during the equivalence process, establishes a quantitative relationship between the equivalent delay and the relative angle between the fast axes of the waveplates, and finally obtains a special delay delay device suitable for optimal polarization imaging systems by bonding the two waveplates together, thus solving the problem of difficulty in constructing high-performance systems.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] An arbitrary delay waveplate generation device based on a standard waveplate comprises a standard waveplate one, a graduated fast-axis marker disk one, a standard waveplate two, a graduated fast-axis marker disk two, and a non-polarizing adhesive layer. The standard waveplate one and standard waveplate two are common polarization phase delay devices; the incident light beam undergoes birefringence within them, and the phase difference between the o-ray and e-ray alters the polarization state of the outgoing light. Besides its own delay, the fast-axis direction, as another important parameter of the waveplate, is crucial in determining the outgoing polarization state. The graduated fast-axis marker disk one and standard waveplate two, combined with the standard waveplate one and standard waveplate two, enable the positioning and precise adjustment of the waveplate's fast axis. According to the equivalence theorem of optical systems, combining standard waveplate 1 and standard waveplate 2 with different fast axis angles can equivalently produce a waveplate with arbitrary polarization. The phase delay of this equivalent waveplate is independent of the initial orientation of the fast axes of standard waveplate 1 and standard waveplate 2, and only satisfies a certain functional relationship with the relative angles between the fast axes; the equivalent fast axis is always 45°. Therefore, provided that the initial positions of the fast axes of standard waveplate 1 and standard waveplate 2 are consistent, by accurately adjusting the fast axis angles between the waveplates according to the baselines on graduated fast axis marker disks 1 and 2, and then bonding them together using a non-polarizing adhesive layer, any desired delay plate can be generated without complex customization.

[0008] Any polarization modulation device has a corresponding Mueller matrix form, where the delay is D and the angle between the fast axis and the vertical direction is α. The Mueller matrix of a waveplate can be expressed as:

[0009]

[0010] Given two quarter-wave plates (denoted as Standard Waveplate 1 and Standard Waveplate 2), both designed for single wavelength, and with a 90° phase delay when the incident light is at its corresponding operating wavelength, and the initial directions of their fast axes being 0° and b° respectively (both with the vertical direction as the reference axis), the Mueller matrices of the two waveplates are as follows:

[0011]

[0012]

[0013] With standard waveplate two positioned at the front of the optical path, and standard waveplate one immediately following behind, the mathematical form of the entire optical path, based on the relative positions of the two waveplates, is as follows:

[0014] S out =M1×M2×S in (4)

[0015] S in the formula in With S out Let M represent the incident light Stokes vectors, respectively. E=M1×M2 is also known as the system matrix of the optical path, and the standard waveplate 2 can be directly represented by a Mueller matrix, or it can be equivalently represented as:

[0016] M2=R(-b)×M1×R(b) (5)

[0017] In equation (5), R represents a rotation matrix. Multiplying M1 by a rotation matrix on the left and right respectively means rotating M1 as a whole. Since the delay of waveplate M1 is the same as that of M2, and the fast axis direction is 0°, equation (5) actually means: rotating standard waveplate one from its initial position on the fast axis by b°, and the waveplate after rotation is standard waveplate two. In addition, the mathematical rotation matrix R also corresponds to the Mueller matrix of the polarization rotator in the optical system. This device has optical rotation characteristics and can rotate the vibration direction of the incident polarized light by a certain angle. The matrix form of R(b) is as follows:

[0018]

[0019] In summary:

[0020] M E =M1×R(-b)×M1×R(b) (7)

[0021] According to the equivalence theorem of optics, an optical system containing several waveplates and several polarization rotators can be equivalently represented as a system containing only one waveplate and one polarization rotator. Therefore:

[0022] M E =M1×M2=M LR ×R(θ) (8)

[0023] Thus, the matrix M in equation (8) is... LR Let M represent a new waveplate with a phase delay of d and an angle of θ between its fast axis and the vertical direction, and let R(θ) be a new polarization rotator with a rotation angle of θ. This equivalent method can also be understood as: M E Viewed as an elliptical retarder, which can be equivalent to a linear retarder combined with a circular retarder, the linear retarder corresponds to the waveplate M. LR The circular retarder corresponds to the rotation matrix R(θ). Therefore, using a combination of two quarter-wave plates can effectively create a new retarder, and the resulting rotation matrix is ​​independent of the phase delay caused by the optical path, M. LR The matrix form of R(θ) is:

[0024]

[0025]

[0026] Let Me =M LR ×R(θ), M is obtained sequentially using matrix multiplication. E With M e :

[0027]

[0028]

[0029] Matrix M e In this context, m1-m9 represent the elements at corresponding positions in the matrix:

[0030] m1=cos(2θ)[cos 2 (2o)+sin 2 (2o)cos(d)]-sin(2θ)[cos(2o)sin(2o)-cos(2o)sin(2o)cos(d)];

[0031] m2=sin(2θ)[cos 2 (2o)+sin 2 (2o)cos(d)]+cos(2θ)[cos(2o)sin(2o)-cos(2o)sin(2o)cos(d)];

[0032] m3 = sin(2o)sin(d);

[0033] m4=cos(2θ)[cos(2o)sin(2o)-cos(2o)sin(2o)cos(d)]-sin(2θ)[sin 2 (2o)+cos 2 [(2o)cos(d)];

[0034] m5=cos(2θ)[sin 2 (2o)+cos 2 (2o)cos(d)]+sin(2θ)[cos(2o)sin(2o)-cos(2o)sin(2o)cos(d)];

[0035] m6 = -cos(2o)sin(d);

[0036] m7=-cos(2θ)sin(2o)sin(d)-sin(2θ)cos(2o)sin(d);

[0037] m8=cos(2θ)cos(2o)sin(d)-sin(2θ)sin(2o)sin(d);

[0038] m9=cos(d) (13)

[0039] According to the property of matrix equality, we can consider that the elements at corresponding positions are equal. Therefore, using the elements in the second row and fourth column and the third row and fourth column of the two matrices respectively: m3 / m6=sin(2b) / 0, we can obtain:

[0040]

[0041] Therefore, the angle between the fast axis and the vertical direction is calculated to be θ = 45°. This means that at the design wavelength, the fast axis direction of the newly equivalent waveplate of the same 1 / 4 waveplate with initial fast axis directions of 0° and b° is always equal to 45°. Substituting this conclusion into matrix M... e The new matrix is ​​then simplified as follows:

[0042]

[0043] Finally, matrix M is used. e * With matrix M E The other elements in the equation yield the following equation:

[0044]

[0045] To ensure that all the above equations hold true, after combining them, the initial direction b of the fast axis and the rotation angle θ of the standard waveplate 2 should satisfy the following relationships:

[0046] b = 90 - 0.5 × d (17)

[0047] θ=b-90 (18)

[0048] Equation (17) can also be seen as a function of the equivalent waveplate delay d and the relative angle between the fast axes of standard waveplate 1 and standard waveplate 2 (because the initial positions of the two waveplates are 0° and b° respectively, the angle between their fast axes is the same as the initial direction of the fast axis of M2, which is b). Therefore, given the required delay, a corresponding angle can be solved. For example, when d = 132°, the angle between the fast axes of the two waveplates should be 24°. In addition, when the initial positions of the fast axes of the two waveplates become a and a+b, they can actually be regarded as a whole and rotated by a° from the positions of 0° and b°. Equation (8) then becomes:

[0049] M E =R(-a)×M1×M2×R(a)=R(-a)×M LR ×R(θ)×R(a) (19)

[0050] Therefore, the equivalent delay is independent of the initial position of the fast axis of the waveplates. In the equivalent process, only the relative angle between the two waveplates needs to be determined. The initial position actually affects the direction of the fast axis of the equivalent waveplate. From equation (19), it can be determined that the direction of the fast axis becomes 45-a. Finally, the initial position of the fast axis of the waveplates does not need to be considered during the bonding process, but it is necessary to ensure that they are bonded to each other at the angle calculated by equation (17). Therefore, the fast axis directions of the two waveplates need to be aligned before bonding, and the relative angle is modulated using a graduated fast axis marking disk. If the 1 / 4 waveplate used has a single-wavelength characteristic, then the result after bonding is also a single-wavelength equivalent delay. The same applies to achromatic characteristics.

[0051] The principle of this invention is as follows: Utilizing the birefringence effect that occurs when a light beam passes through a waveplate and introduces polarization phase delay in different polarization directions, a combined waveplate is formed by combining two standard waveplates at different angles. This allows the transmitted light to generate different phase delays and a fixed fast axis direction after passing through the combined waveplate. By combining a graduated fast axis marking disk with a non-polarizing adhesive layer, a new delay device based on a double waveplate is obtained, which meets the requirements of non-standard delay of the waveplate for the optimization of polarization imaging or detection performance.

[0052] Compared with the prior art, the present invention has the following advantages:

[0053] (1) Compared with the standard waveplates that are readily available in the traditional way, the present invention can generate any non-standard polarization delay, so that the phase delay is no longer limited to half-wave or quarter-wave design.

[0054] (2). Compared with the traditional method of specially customizing non-standard waveplates, the present invention only needs to use common and readily available single-wavelength 1 / 4 waveplates to obtain special delay amounts, which effectively reduces the acquisition cycle and cost. Furthermore, if an achromatic 1 / 4 waveplate is used, the waveplate with any delay amount obtained will also inherit the corresponding achromatic characteristics. Therefore, neither achromatic nor single-wavelength waveplates need to be specially customized.

[0055] (3) Compared with the precision of traditional custom waveplates, since the current standard 1 / 4 waveplate is relatively mature in production and can achieve a high phase delay precision, the combined waveplate in this method can also ensure that the equivalent delay is kept at a high precision.

[0056] (4) Compared with traditional custom Fresnel prisms, the arbitrary polarization delay waveplate proposed in this invention can guarantee a larger field of view, and is particularly suitable for constructing an optimal rotating waveplate polarization imaging system. Attached Figure Description

[0057] Figure 1 This is a schematic diagram of an arbitrary delay waveplate generation device based on a standard waveplate according to the present invention.

[0058] Figure label:

[0059] 1. Standard waveplate one; 2. Graduated fast axis indicator disk one; 3. Standard waveplate two; 4. Graduated fast axis indicator disk two; 5. Non-polarizing adhesive layer. Detailed Implementation

[0060] The present invention will be further described below with reference to the accompanying drawings and specific examples.

[0061] As attached Figure 1 As shown, an arbitrary delay waveplate generating device based on standard waveplates is described. In this device, 1 and 3 are standard quarter-waveplates (standard waveplate one and standard waveplate two), 2 and 4 are graduated fast-axis marking disks (graduated fast-axis marking disk one and graduated fast-axis marking disk two), and 5 is a non-polarizing adhesive layer. When two standard waveplates satisfy a certain relative angle between their fast axes, a new arbitrary delay waveplate M is equivalently generated. LR And a polarization rotator R that does not affect the phase delay of the light wave and has optical rotation.

[0062] Specifically, the standard waveplate one and standard waveplate two, as common polarization phase delay devices, cause birefringence of the incident light beam within them. The phase difference between the o-ray and e-ray alters the polarization state of the outgoing light. Besides their inherent delay, the fast axis direction, another crucial parameter of the waveplate, is also key to determining the outgoing polarization state. The graduated fast axis indicator disks one and two, combined with the standard waveplates one and two, enable the positioning and precise adjustment of the waveplate's fast axis. According to the equivalence theorem of optical systems, combining the standard waveplates one and two at different fast axis angles can effectively create an equivalent waveplate with arbitrary polarization. The phase delay of this equivalent waveplate is independent of the initial orientation of the fast axes of the standard waveplates one and two, and only satisfies a certain functional relationship with the relative angles between the fast axes; the equivalent fast axis is always 45°. Therefore, under the premise of ensuring that the initial positions of the fast axes of standard waveplate one and standard waveplate two are consistent, the angle between the fast axes of the waveplates can be accurately adjusted according to the baselines on the graduated fast axis marking disk one and the graduated fast axis marking disk two. After bonding with a non-polarizing adhesive layer, any desired delay plate can be generated without complex customization.

[0063] Accordingly, the present invention also provides a method for generating an arbitrary delay waveplate based on a standard waveplate, applied to the aforementioned waveplate generating apparatus, the method comprising the following steps:

[0064] 1) Mount standard waveplate one and standard waveplate two on graduated fast axis marking disk one and graduated fast axis marking disk two, respectively;

[0065] 2) Adjust the initial orientation of the fast axis of standard waveplate one and standard waveplate two to be parallel to each other;

[0066] 3) Determine the required equivalent phase retardation. Based on the equivalence theorem for optical systems, determine the functional relationship between the equivalent retardation and the fast axis angle between the waveplates. The corresponding functional relationship is:

[0067] b = 90 - 0.5 × d

[0068] Where b is the angle between the fast axes of the two waveplates, and d is the required equivalent delay.

[0069] 4) Keep the first standard waveplate in place, and rotate the second standard waveplate by the corresponding angle according to the scale on the first fast axis indicator, so that the included angle of the fast axis satisfies the angle value obtained in step 3).

[0070] 5) By using a non-polarizing adhesive layer to bond waveplates, any desired polarization delay plate can be obtained.

[0071] The specific derivation process of the functional relationship in step 3) is as follows:

[0072] Any polarization modulation device has a corresponding Mueller matrix form, where the delay is D and the angle between the fast axis and the vertical direction is α. The Mueller matrix of a waveplate can be expressed as:

[0073]

[0074] Given two quarter-wave plates (denoted as Standard Waveplate 1 and Standard Waveplate 2), both designed for single wavelength, and with a 90° phase delay when the incident light is at its corresponding operating wavelength, and the initial directions of their fast axes being 0° and b° respectively (both with the vertical direction as the reference axis), the Mueller matrices of the two waveplates are as follows:

[0075]

[0076]

[0077] With standard waveplate two positioned at the front of the optical path, and standard waveplate one immediately following behind, the mathematical form of the entire optical path, based on the relative positions of the two standard waveplates, is as follows:

[0078] S out =M1×M2×S in (4)

[0079] S in the formula in With S out Let M represent the incident light Stokes vectors, where M is the incident light vector. E =M1×M2 is also known as the system matrix of the optical path, and the standard waveplate 2 can be directly represented by a Mueller matrix, or it can be equivalently represented as:

[0080] M2=R(-b)×M1×R(b) (5)

[0081] In equation (5), R represents a rotation matrix. Multiplying M1 by a rotation matrix on the left and right respectively means rotating M1 as a whole. Since the delay of waveplate M1 is the same as that of M2, and the fast axis direction is 0°, equation (5) actually means: rotating standard waveplate one from its initial position on the fast axis by b°, and the waveplate after rotation is standard waveplate two. In addition, the mathematical rotation matrix R also corresponds to the Mueller matrix of the polarization rotator in the optical system. This device has optical rotation characteristics and can rotate the vibration direction of the incident polarized light by a certain angle. The matrix form of R(b) is as follows:

[0082]

[0083] In summary:

[0084] M E =M1×R(-b)×M1×R(b) (7)

[0085] According to the equivalence theorem of optics, an optical system containing several waveplates and several polarization rotators can be equivalently represented as a system containing only one waveplate and one polarization rotator. Therefore:

[0086] M E =M1×M2=M LR ×R(θ) (8)

[0087] Thus, the matrix M in equation (8) is... LR Let M represent a new waveplate with a phase delay of d and an angle of θ between its fast axis and the vertical direction, and let R(θ) be a new polarization rotator with a rotation angle of θ. This equivalent method can also be understood as: M E Viewed as an elliptical retarder, which can be equivalent to a linear retarder combined with a circular retarder, the linear retarder corresponds to the waveplate M. LR The circular retarder corresponds to the rotation matrix R(θ). Therefore, using a combination of two quarter-wave plates can effectively create a new retarder, and the resulting rotation matrix is ​​independent of the phase delay caused by the optical path, M. LR The matrix form of R(θ) is:

[0088]

[0089]

[0090] Let M e =M LR ×R(θ), M is obtained sequentially using matrix multiplication. E With M e :

[0091]

[0092]

[0093] Matrix M e where m1 - m9 in it represent the elements at the corresponding positions of the matrix:

[0094] m1 = cos(2θ)[cos 2 (2o)+sin 2 (2o)cos(d)] - sin(2θ)[cos(2o)sin(2o) - cos(2o)sin(2o)cos(d)];

[0095] m2 = sin(2θ)[cos 2 (2o)+sin 2 (2o)cos(d)] + cos(2θ)[cos(2o)sin(2o) - cos(2o)sin(2o)cos(d)];

[0096] m3 = sin(2o)sin(d)

[0097] m4 = cos(2θ)[cos(2o)sin(2o) - cos(2o)sin(2o)cos(d)] - sin(2θ)[sin 2 (2o)+cos 2 (2o)cos(d)];

[0098] m5 = cos(2θ)[sin 2 (2o)+cos 2 (2o)cos(d)] + sin(2θ)[cos(2o)sin(2o) - cos(2o)sin(2o)cos(d)];

[0099] m6 = -cos(2o)sin(d);

[0100] m7 = -cos(2θ)sin(2o)sin(d) - sin(2θ)cos(2o)sin(d);

[0101] m8 = cos(2θ)cos(2o)sin(d) - sin(2θ)sin(2o)sin(d);

[0102] m9 = cos(d) (13)

[0103] According to the property of matrix equality, we can consider that the elements at corresponding positions are equal. Therefore, using the elements in the second row and fourth column and the third row and fourth column of the two matrices respectively: m3 / m6=sin(2b) / 0, we can obtain:

[0104]

[0105] Therefore, we can calculate that o = 45°, meaning that at the design wavelength, the newly equivalent fast axis direction of the same 1 / 4 waveplate with initial directions of 0° and b° is always equal to 45°. Substituting this conclusion into matrix M... e The new matrix is ​​then simplified as follows:

[0106]

[0107] Finally, matrix M is used. e * With matrix M E The other elements in the equation yield the following:

[0108]

[0109] To ensure that all the above equations hold true, after combining them, the initial direction b of the fast axis of standard waveplate 2 should satisfy the following relationship:

[0110] b = 90 - 0.5 × d (17)

[0111] Equation (17) can also be viewed as a function of the equivalent waveplate delay d and the relative angle between the fast axes of standard waveplate 1 and standard waveplate 2 (because the initial positions of the two waveplates are 0° and b° respectively, the angle between their fast axes is the same as the initial direction of the fast axis of standard waveplate 2, which is b). Therefore, given the required delay, a corresponding angle can be solved. For example, when d = 132°, the angle between the fast axes of the two waveplates should be 24°.

[0112] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any substitutions or additions that can be understood by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A device for generating arbitrary delay waveplates based on standard waveplates, characterized in that, It consists of a standard waveplate one (1), a graduated fast axis indicator disk one (2), a standard waveplate two (3), a graduated fast axis indicator disk two (4), and a non-polarizing adhesive layer (5); The standard waveplate one (1) and standard waveplate two (3) serve as polarization phase delay devices, causing the incident beam to undergo birefringence within them. The phase difference between the o-ray and the e-ray causes the polarization state of the outgoing light to change. The graduated fast axis indicator disk one (2) and the graduated fast axis indicator disk two (4) are combined with the standard waveplate one (1) and the standard waveplate two (3) to realize the positioning and precise adjustment of the fast axis of the waveplate; The positioning and precise adjustment of the fast axis of the waveplate includes: The standard waveplate one (1) and standard waveplate two (3) are combined according to different fast axis angles to form an equivalent waveplate with arbitrary delay. The phase delay of the equivalent waveplate with arbitrary delay is independent of the initial orientation of the fast axis of the standard waveplate one (1) and standard waveplate two (3), and only satisfies a certain functional relationship with the relative angle between the fast axes of the standard waveplate one (1) and standard waveplate two (3). The direction of the equivalent fast axis is always 45°. Ensure that the initial positions of the fast axis of standard waveplate 1 (1) and standard waveplate 2 (3) are consistent. According to the baseline on the fast axis marking disk 1 (2) and the fast axis marking disk 2 (4), accurately adjust the fast axis angle between standard waveplate 1 (1) and standard waveplate 2 (3). After bonding with the non-polarizing adhesive layer (5), the desired arbitrary delay waveplate is generated. The graduated fast axis indicator disk one (2) and the graduated fast axis indicator disk two (4) are combined with the standard waveplate one (1) and the standard waveplate two (3) to achieve joint rotation. This not only positions the initial position of the fast axis of the waveplate, but also precisely adjusts the angle between the fast axes of the standard waveplate one (1) and the standard waveplate two (3) according to the baseline on the indicator disk.

2. The device for generating arbitrary delay waveplates based on standard waveplates according to claim 1, characterized in that: The standard waveplate one (1) and standard waveplate two (3) are standard delay waveplates.

3. The device for generating arbitrary delay waveplates based on standard waveplates according to claim 2, characterized in that, The standard waveplate one (1) and standard waveplate two (3) are single-wavelength or achromatic waveplates, with a phase delay of any one of 1 / 4 wavelength, 1 / 2 wavelength, or full wavelength, and a phase delay accuracy of any one of multi-level, zero-level, or true zero-level, with the wavelength being the same as the laser wavelength.

4. The device for generating arbitrary delay waveplates based on standard waveplates according to claim 1, characterized in that: The non-polarizing adhesive layer (5) is used to bond the two standard waveplates after the fast axis angle has been adjusted, thereby obtaining a waveplate with arbitrary delay.

5. A method for generating an arbitrary delay waveplate based on a standard waveplate, the method being applied to the arbitrary delay waveplate generating apparatus based on a standard waveplate as described in any one of claims 1-4, characterized in that, The method includes the following steps: 1) Mount standard wave plate one (1) and standard wave plate two (3) on the graduated fast axis indicator disk one (2) and the graduated fast axis indicator disk two (4) respectively; 2) Adjust the initial orientation of the fast axis of standard waveplate 1 (1) and standard waveplate 2 (3) to be parallel to each other; 3) Determine the equivalent phase delay and, based on the functional relationship between the equivalent delay and the fast axis angle between the waveplates according to the equivalence theorem of optical systems, determine the fast axis angle between standard waveplate one (1) and standard waveplate two (3). The functional relationship is as follows: in, b The angle between the fast axes of the two standard waveplates. d This is the desired equivalent phase delay. 4) Standard waveplate one (1) remains stationary, and standard waveplate two (3) rotates by the corresponding angle according to the scale on the graduated fast axis indicator disk two (4) so ​​that the fast axis angle satisfies the fast axis angle value obtained in step 3). 5) Use the non-polarizing adhesive layer (5) to bond the waveplate and obtain the waveplate with the desired arbitrary delay.

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