CN-122016107-A - Transparent object stress detection device and method based on full Stokes polarization super surface

CN122016107ACN 122016107 ACN122016107 ACN 122016107ACN-122016107-A

Abstract

The invention discloses a transparent object stress detection device and method based on a full Stokes polarization super surface, which mainly solve the problems that the existing detection method is easy to introduce systematic errors, inaccurate in measurement results, poor in dynamic response and the like. The device comprises a light source, a polarizer, a super-surface polarization-detecting element, a detector and a processing module, wherein the polarizer, the super-surface polarization-detecting element and the detector are sequentially arranged along an emergent light path of the light source, the polarizer is a linear polarizer, an included angle between the polarization direction and an emergent light optical axis of the light source is 0 degree, the super-surface polarization-detecting element is of a periodic structure, linearly polarized light is separated into four diffracted lights with different polarization states by the super-surface polarization-detecting element after passing through a transparent object to be detected, the detector is used for receiving the four diffracted lights and generating a corresponding light intensity diagram, and the processing module is connected with the detector and used for receiving the light intensity diagram, calculating and outputting stress distribution conditions of the transparent object to be detected.

Inventors

WANG GUOXI
WANG WANJUN
LI SIQI
ZHAO JIAQI
ZHANG WENFU

Assignees

中国科学院西安光学精密机械研究所

Dates

Publication Date: 20260512
Application Date: 20260413

Claims (10)

1. A transparent object stress detection device based on full Stokes polarization super surface is characterized in that: The detector comprises a light source (1), a polarizer (2), a super-surface polarization-detecting element (4), a detector (5) and a processing module, wherein the polarizer (2), the super-surface polarization-detecting element (4) and the detector (5) are sequentially arranged along an emergent light path of the light source (1); The super-surface polarization detection device comprises a polarizer (2), a super-surface polarization detection element (4), a light source (1), a light source (2) and a light source (3), wherein the polarizer is a linear polarizer, the included angle between the polarization direction and the optical axis of the emergent light of the light source (1) is 0 degree, and the emergent light is used for converting the emergent light into linear polarized light; the detector (5) is used for receiving the four beams of diffracted light and generating a corresponding light intensity map; the processing module is connected with the detector (5) and is used for receiving the light intensity graph transmitted by the detector (5), calculating and outputting the stress distribution condition of the transparent object (3) to be detected.
2. The transparent object stress detection device based on a full stokes polarization super surface according to claim 1, wherein: The super-surface polarization-maintaining element (4) is designed based on a matrix Fourier optical principle, a Jones matrix is adopted as a spatial distribution function, diffraction behaviors of the super-surface polarization-maintaining element (4) are described through matrix Fourier transformation, each diffraction order of the super-surface polarization-maintaining element (4) corresponds to one Jones matrix, and a plurality of diffraction orders work simultaneously.
3. The transparent object stress detection device based on a full stokes polarization super surface according to claim 2, wherein: The super-surface polarization-detecting element (4) comprises a substrate layer (41) and a plurality of nano-columns (42) which are arranged on the substrate layer (41) in an array manner, wherein the plurality of nano-columns (42) are arranged on one side, far away from the detector (5), of the substrate layer (41) according to a super-surface transmission phase principle and are used for separating received linearly polarized light into four beams of diffracted light with different polarization states.
4. A transparent object stress detection device based on a full stokes polarization subsurface according to claim 1 or 2 or 3, characterized in that: The detector (5) selects a CMOS image sensor.
5. The transparent object stress detection method based on the full Stokes polarization super surface is characterized by comprising the following steps of: Assembling the transparent object stress detection device based on the full Stokes polarization super surface according to any one of claims 1 to 4, and coaxially placing a transparent object (3) to be detected between a polarizer (2) and a super surface polarization detection element (4); step 2, the emergent light of the light source (1) is converted into linear polarized light through the polarizer (2), reaches the super-surface polarization-detecting element (4) after passing through the transparent object (3) to be detected, is separated into four beams of diffracted light with different polarization states through the super-surface polarization-detecting element (4), and is transmitted to the detector (5); step 3, the detector (5) generates a corresponding light intensity graph from the four beams of diffracted light and transmits the light intensity graph to the processing module; And 4, the processing module obtains the stress distribution of the transparent object (3) to be detected by adopting a phase shift method based on the corresponding light intensity graph, so that the transparent object stress detection based on the full Stokes polarization super surface is realized.
6. The transparent object stress detection method based on the full stokes polarization super surface according to claim 5, wherein the method comprises the following steps: in the step 2, the four diffracted lights with different polarization states are respectively horizontal linear polarized light, 57-degree linear polarized light, left-hand 60-degree elliptical polarized light and right-hand 60-degree elliptical polarized light.
7. The method for detecting the stress of the transparent object based on the full stokes polarization super surface according to claim 6, wherein the step 4 is specifically: step 4.1, the processing module respectively converts the polarization states of diffracted lights corresponding to the light intensity patterns into a Mueller matrix of the super-surface polarization-detecting element (4) based on the corresponding light intensity patterns; Step 4.2, combining the Mueller matrix of the super-surface polarization-detecting element (4), the Mueller matrix M 1 of the polarizer (2), the Mueller matrix M 2 of the transparent object (3) to be detected and the light intensity of four beams of diffracted light, and solving to obtain the phase delay amount distribution and stress direction angle distribution of the transparent object (3) to be detected; And 4.3, further calculating stress distribution of the transparent object (3) to be detected based on the phase delay amount distribution of the transparent object (3) to be detected, thereby realizing transparent object stress detection based on the full Stokes polarization super surface.
8. The transparent object stress detection method based on the full stokes polarization super surface according to claim 7, wherein: In step 4.1, the mueller matrix of the subsurface polarization-detecting element (4) comprises a mueller matrix of horizontally linearly polarized light Mueller matrix of 57-degree linearly polarized light Mueller matrix of left-handed 60-degree elliptical polarized light Mueller matrix of right-handed 60-degree elliptical polarized light The expressions are as follows: ; ; ; ; in step 4.2, the muller matrix M 1 of the polarizer (2) is: ; the Mueller matrix M 2 of the transparent object (3) to be measured is as follows: ; Wherein, the For the phase retardation of the transparent object (3) to be measured, Is the stress direction angle of the transparent object (3) to be measured.
9. The transparent object stress detection method based on the full stokes polarization super surface according to claim 8, wherein: In step 4.2, the phase retardation of the transparent object (3) to be detected is calculated by the following formula; ; Wherein I A is the light intensity of horizontal linear polarized light, I B is the light intensity of 57-degree linear polarized light, I C is the light intensity of left-hand 60-degree elliptical polarized light, and I D is the light intensity of right-hand 60-degree elliptical polarized light; the stress direction angle of the transparent object (3) to be measured is calculated by the following formula: 。
10. The transparent object stress detection method based on the full stokes polarization super surface according to claim 9, wherein: in step 4.3, the stress of the transparent object (3) to be measured is calculated by the following formula: ; wherein, delta represents the stress of the transparent object (3) to be measured, d represents the thickness of the transparent object (3) to be measured, and lambda represents the wavelength of the light emitted by the light source (1).

Description

Transparent object stress detection device and method based on full Stokes polarization super surface Technical Field The invention relates to a transparent object stress detection device and method, in particular to a transparent object stress detection device and method based on a full Stokes polarization super surface. Background In optical systems, various transparent elements are widely used. However, the transparent element is limited by the production and manufacturing process, residual stress is commonly existed in the transparent element, shrinkage, deformation, warping, even cracking and other problems are easily caused in the use process, the problems not only can change the surface morphology of the transparent element and degrade the optical performance of the transparent element, but also directly relate to the service life and operation safety of the product. Therefore, the stress measurement of the transparent element is carried out, and the method has important significance for guaranteeing the structural strength and the optical performance of the transparent element. Currently, the stress measurement methods of transparent elements are mainly classified into two major types, namely a mechanical method and an optical detection method. The traditional optical detection method needs to acquire polarization information by rotating an analyzer and a quarter wave plate, and is difficult to realize real-time dynamic monitoring of stress. In order to break through the limitation, researchers propose to adopt an amplitude division method to synchronously acquire polarization data in different directions, but the method needs to be provided with a plurality of photoelectric sensors, so that the problems of asynchronous acquisition of polarization images, poor picture matching degree and the like are easily caused, and the measurement accuracy is seriously influenced. In order to effectively solve the technical pain points, a stress detection scheme based on the super surface is generated. The super surface is composed of a nano unit array with a sub-wavelength scale, and can realize accurate local regulation and control on the phase, amplitude and polarization state of incident light. By virtue of excellent light field regulation and control capability and flexible structural design characteristics, the super surface can replace traditional optical elements such as lenses, gratings, beam splitters and the like, greatly reduces the volume of the device, is highly compatible with the development trend of miniaturization and integration of the current optical platform, and has great application potential in the field of stress detection. The method is particularly critical, the super surface can integrate three core functions of light splitting, polarization detection and imaging on a single-piece sub-wavelength structure in a planarization mode, the volume and the adjustment complexity of the system are obviously reduced, and the breakthrough of acquiring complete polarization information through single exposure is realized by means of the parallel polarization sampling capability of the system. The technology innovation realizes the span-type improvement on the detection precision, the detection speed and the system integration level, and opens up a brand new technical path for the on-line stress monitoring of the transparent element. Currently, various methods related to stress detection have been proposed in the patent: The patent of China patent publication No. CN111811718A proposes a transparent object stress detection device based on a micro-polarizer array, which comprises a light source, a light homogenizing plate, a polarizer, a 1/4 wave plate, a micro-polarizer array and a light intensity detector which are sequentially arranged, wherein the 1/4 wave plate is arranged above a sample to be detected, linear polarized light emitted from the polarizer is converted into circular polarized light after passing through the 1/4 wave plate, the circular polarized light is decomposed into two polarized lights with mutually perpendicular polarization directions after passing through the sample to be detected, and the two polarized lights finally reach the photosensitive surface of the light intensity detector after passing through the micro-polarizer array. The light intensity detector acquires image information, and then the stress value of the whole area of the sample to be detected can be obtained through calculation of the image processing element. However, the detection device needs multi-stage discrete components such as a polarizer, a 1/4 wave plate, a micro-polarizer array and the like, has high light energy loss, is easy to introduce systematic errors due to the alignment error of the pixels of the micro-polarizer array and the pixels of the light intensity detector and the insufficient polarization extinction ratio of the micro-polarizer array, is difficult to flexibly cover the polarization