A system and method for high-precision synchronous real-time measurement of temperature field and deformation field

Abstract

The present application proposes a system and method for high-precision synchronous real-time measurement of temperature field and deformation field. The system includes a laser modulation component, the collimated laser beam emitted by which is incident on the optical surface of the object to be measured through a prism component; the laser reflection beam reflected by the optical surface of the object to be measured is in a collimated state and is reflected to the polarization measurement component through the prism component; the infrared band beam emitted by the optical surface of the object to be measured is transmitted to the infrared thermal imaging device through the prism component for imaging; the polarization measurement component converges the interference beam result of the laser reflection beam into a diffraction spot; the image acquisition and processing system is set downstream of the filter lens along the optical path direction of the laser reflection beam to collect the laser image diffraction spot and perform polarization phase shift for coherent gradient sensing measurement and post-processing calculation; the image formed by the infrared thermal imaging device is processed by the image acquisition and processing system. The present application can accurately and effectively realize the real-time accurate synchronous measurement of the temperature field and deformation field of the object to be measured.

Description

Technical Field

[0001] The present application relates to the field of on-site real-time manufacturing technologies such as semiconductor devices and laser directed energy deposition manufacturing, and in particular to a system and method for high-precision synchronous real-time measurement of temperature fields and deformation fields. Background Art

[0002] Coherent gradient sensor is a full-field interference type gradient coherent optical measurement method based on dual grating common optical path shearing interference technology. The measurement principle of reflective coherent gradient sensor is that the object wave enters the dual grating system to generate interference. Through the phase analysis of the interference fringe field before deformation (zero fringe field) and after deformation, the full-field off-plane displacement gradient data of the object surface can be solved. In particular, the polarization phase shift coherent gradient sensor based on polarization grating has its full-field, real-time, high-precision and high-sensitivity measurement advantages, and has been widely used in the field of macro and micro measurement of various materials and structures.

[0003] However, in the field of on-site real-time manufacturing technology such as semiconductor devices and directed energy deposition, the deformation field is mostly induced by the temperature field, which involves a large number of situations that require the measurement of temperature field and deformation field, and requires synchronous real-time measurement of deformation field and temperature field. In the relevant technologies of synchronous real-time measurement of temperature field and deformation field, there are currently relevant mature application processing methods, including multispectral cameras based on colorimetry, digital image correlation methods based on fluorescent speckle, etc. However, these methods generally solve displacement, and because they are all incoherent visual test methods, the resolution and accuracy of the obtained deformation fields such as strain field and deformation gradient field are generally not high compared with coherent optical methods. At present, the prospect of high-precision real-time measurement applications in the industry is limited.

[0004] Therefore, how to develop a high-precision deformation field and temperature field synchronous real-time measurement device based on high-precision coherent gradient sensing measurement technology is a technical problem that technical personnel in this field urgently need to solve. Summary of the invention

[0005] The present application aims to solve at least one of the technical problems in the related art to a certain extent. The present application can accurately and effectively realize the real-time and accurate measurement of the deformation field and temperature field of the object to be measured, the measurement principle is simple, and the application scope and application scenarios of the coherent gradient sensor are further expanded.

[0006] To achieve the above-mentioned purpose, the first aspect of the present application proposes a system for synchronously measuring temperature field and deformation field in real time with high precision, comprising:

[0007] A laser modulation component, wherein the collimated laser beam emitted by the laser modulation component is incident on the optical surface of the object to be measured through the prism component; the laser reflected beam in the visible light band reflected by the optical surface of the object to be measured is in a collimated state and is reflected to the polarization measurement component through the prism component; the infrared band beam emitted by the optical surface of the object to be measured is transmitted through the prism component to the infrared thermal imaging device for imaging;

[0008] The polarization measurement component comprises a polarizer, a transmission grating group and a filter lens which are sequentially arranged along the optical path direction of the laser reflected light beam; the transmission grating group comprises a front polarization transmission grating and a rear polarization transmission grating, the laser reflected light beam is diffracted on the front polarization transmission grating, and the diffracted light beam passing through the front polarization transmission grating is diffracted again on the rear polarization transmission grating to form an interference light beam; the interference light beam is converged into a diffraction spot through the filter lens; and

[0009] An image acquisition and processing system is arranged downstream of the filter lens along the optical path direction of the laser reflected light beam, and is used to acquire the laser image diffraction spot and perform polarization phase shift to perform coherent gradient sensing measurement and post-processing calculation; the image formed by the infrared thermal imaging device is processed by the image acquisition and processing system.

[0010] In some embodiments, the prism assembly includes a beam splitter, a dichroic mirror and a plane reflector; the collimated laser beam is incident on the optical surface of the object to be measured through the beam splitter and the dichroic mirror; the laser reflected light beam is transmitted from the reflective surface of the beam splitter and the dichroic mirror to the plane reflector and then turned to the polarization measurement assembly to keep the laser reflected light beam horizontal; the infrared band light beam is split by the dichroic mirror and transmitted to the infrared thermal imaging device.

[0011] In some embodiments, the laser modulation assembly includes a laser that provides laser light, and a beam expanding convex lens and a collimating convex lens that are sequentially arranged along the optical path of the collimated laser beam.

[0012] In some embodiments, the beam expanding convex lens and the collimating convex lens are both plano-convex lenses and are both disposed on a slider; the slider is adapted to a slide rail extending along the optical path direction of the collimated laser beam.

[0013] In some embodiments, the dichroic mirror is a long-wave pass dichroic mirror, so that the infrared band light beam is transmitted and imaged on the target surface of the infrared thermal imaging device; and at the same time, the collimated laser beam is reflected.

[0014] In some embodiments, the reflective surfaces of the beam splitter prism and the dichroic mirror each include two right-angle optical quartz glass prisms, and the oblique surfaces of the two right-angle optical quartz glass prisms are bonded and coated with a semi-transparent and semi-reflective film or a dichroic film to form the reflective surface.

[0015] In some embodiments, the polarizer is a linear polarizer made of a dichroic material to convert the laser reflected light beam of natural light into linear polarized light.

[0016] In some embodiments, the front polarization transmission grating and the rear polarization transmission grating are both transmissive Ronchi square wave diffraction gratings made of liquid crystal polymer; the duty cycle of the transmissive Ronchi square wave diffraction grating is 1:1.

[0017] In some embodiments, the image acquisition and processing system includes a digital industrial polarization camera integrated with an aperture stop, and a computer image post-processing system.

[0018] In some embodiments, all components except the computer image post-processing system and the infrared thermal imaging device are integrated onto the bottom plate base by a supporting assembly.

[0019] According to the second aspect, the present application proposes a method for high-precision synchronous real-time measurement of temperature field and deformation field, which uses the system described in any of the above embodiments to perform measurement, including the following steps:

[0020] Building the system described in any of the above embodiments;

[0021] Reasonably set the parameters of the infrared thermal imaging device according to the thermal radiation characteristics of the optical surface of the object to be measured, so that the surface temperature value obtained by the infrared thermal imaging device is consistent with the optical surface temperature of the object to be measured;

[0022] The laser modulation component is adjusted according to the characteristics of the optical surface of the object to be measured, and the laser modulation component emits a collimated laser beam and is incident on the optical surface of the object to be measured through a prism component; the laser reflected light beam reflected by the optical surface of the object to be measured is in a collimated state; at the same time, the infrared band light beam emitted by the optical surface of the object to be measured is transmitted through the prism component to the infrared thermal imaging device for imaging;

[0023] Adjusting the clamping state of the polarization measurement assembly so that the grating lines of the front polarization transmission grating and the rear polarization transmission grating are parallel to each other;

[0024] The image acquisition and processing system acquires the image data of the laser image diffraction spot and the infrared thermal imaging device, and performs polarization phase shift coherence gradient sensing measurement and post-processing calculation on the laser image diffraction spot.

[0025] In some embodiments, the surface roughness of the optical surface of the object to be measured after polishing is less than or equal to 0.02 μm.

[0026] In some embodiments, the target surface imaged by the infrared thermal imaging device is orthogonal to the extension direction of the collimated light beam reflected by the optical surface of the object to be measured; the target surface of the digital industrial polarization camera is orthogonal to the extension direction of the interference light beam.

[0027] In some embodiments, the polarization directions of the target surface superpixels of the digital industrial polarization camera are 0°, 45°, 90°, and 135° from left to right and from top to bottom in a clockwise direction, respectively.

[0028] Compared with the prior art, this application has the following advantages:

[0029] This application utilizes the characteristics of polarization phase shift and infrared thermal imager, separates light of different wavelengths through prism components and processes temperature field results; adjusts the polarization state of the interference light beam through polarization measurement components and image acquisition and processing systems to obtain spatial phase shift deformation field results, that is, to achieve synchronous real-time measurement of temperature field and deformation field, with simple principles and convenient operation. It solves the technical difficulties of simultaneous high-precision real-time synchronous and intuitive measurement of temperature field and deformation gradient field, and expands the measurement range; and this application is applicable to real-time measurement of deformation and temperature of various optical surfaces that can reflect mirrors, and realizes the requirements of high-efficiency, non-destructive, easy-to-operate, and widely applicable in-situ real-time multi-information measurement of industrial surfaces.

[0030] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0032] Figure 1 is a schematic diagram of the structure of a system for high-precision synchronous real-time measurement of temperature field and deformation field in one embodiment of the present application;

[0033] Figure 2 is an optical path diagram of a system for high-precision synchronous real-time measurement of temperature field and deformation field in one embodiment of the present application;

[0034] Figure 3 is a spatial position relationship diagram of a part of a system for high-precision synchronous real-time measurement of temperature field and deformation field in one embodiment of the present application;

[0035] Figure 4 is a schematic diagram of the polarization direction of a target surface superpixel of a digital industrial polarization camera in one embodiment of the present application;

[0036] In the figure, 0, bottom plate base; 1, single longitudinal mode laser; 101, laser support; 2, beam expander convex lens; 201, beam expander frame; 202, beam expander support; 203, first slider; 204, first slide rail; 3, collimator convex lens; 301, collimator frame; 302, collimator support; 303, second slider; 4, beam splitter prism; 401, beam splitter prism support; 5, dichroic mirror; 501, dichroic mirror bracket; 502, dichroic mirror support; 6, sample to be tested; 7, plane reflector; 701, plane reflector support; 8, polarizer; 801, polarizer frame; 802, polarizer support; 9, Front liquid crystal polarization Ronchi transmission grating; 901, front grating clamping frame; 902, front grating support; 10, rear liquid crystal polarization Ronchi transmission grating; 1001, rear grating clamping frame; 1002, rear grating support; 11, filter lens; 1101, filter lens frame; 1102, filter lens support; 1103, connecting plate; 12, pixelated polarization camera; 1201, camera support; 1202, one-dimensional pitch stage; 1203, aperture stop; 1204, third slider; 1205, second slide rail; 13, infrared thermal imager; 14, computer image post-processing system; 15, sample workbench. DETAILED DESCRIPTION

[0037] Embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and cannot be construed as limiting the present application. On the contrary, the embodiments of the present application include all changes, modifications and equivalents that fall within the spirit and connotation of the appended claims.

[0038] To achieve the above-mentioned objectives, the first aspect of the present application proposes a system for high-precision synchronous real-time measurement of temperature field and deformation field, comprising a laser modulation component, a polarization measurement component and an image acquisition and processing system; wherein a collimated laser beam emitted by the laser modulation component is incident on the optical surface of the object to be measured through a prism component; a visible light band laser reflection beam reflected by the optical surface of the object to be measured is in a collimated state and is reflected to the polarization measurement component through the prism component; an infrared band beam emitted by the optical surface of the object to be measured is transmitted through the prism component to an infrared thermal imaging device for imaging.

[0039] The laser modulation assembly includes a laser for providing a collimated laser beam, and a beam expansion convex lens 2 and a collimating convex lens 3 arranged in sequence along the optical path of the collimated laser beam. Figure 1The front-to-back direction in the figure is consistent, wherein the front-to-back direction and the optical axis z are shown as marked in the figure. In this embodiment, the laser can be a single longitudinal mode laser 1 and provide a monochromatic laser with a laser wavelength of 532 nm, and the monochromatic laser matches each optical element in this system. The collimated laser beam emitted by the laser is directed toward the negative direction of the z-axis as the optical path direction of the collimated laser beam, that is, the laser emits the collimated laser beam from back to front.

[0040] In this embodiment, after the laser emits a collimated laser beam, the collimated laser beam passes through the beam expanding convex lens 2 and the collimating convex lens 3 in sequence along the optical path of the collimated laser beam and reaches the prism assembly, and after being reflected by the prism assembly, reaches the optical surface of the object to be tested at the bottom of the test sample 6, wherein the laser reflected beam after the collimated laser beam is reflected by the optical surface of the object to be tested is initially in a collimated state, and after the test sample 6 is deformed, the laser reflected beam after the optical surface of the object to be tested is approximately in a collimated state. In the example, the beam expanding convex lens 2 and the collimating convex lens 3 are both plano-convex lenses, and the materials of the beam expanding convex lens 2 and the collimating convex lens 3 are both optical glass K9.

[0041] In this embodiment, the infrared band light beam emitted by the optical surface of the object to be measured is transmitted through the prism assembly to the infrared thermal imaging device for imaging, wherein the infrared thermal imaging device includes an infrared thermal imager 13, that is, the infrared band light beam emitted by the optical surface of the object to be measured is transmitted through the prism assembly to the bottom of the infrared thermal imager 13 for imaging, and the imaging is an infrared thermal image. At the same time, the laser reflection light beam reflected by the optical surface of the object to be measured is reflected to the polarization measurement component through the prism assembly, and at this time, the propagation direction of the collimated laser beam is from front to back, which is opposite to the direction of the initial collimated laser beam, so the prism assembly changes the extension direction of the collimated laser beam.

[0042] It should be explained that in order to ensure that the laser reflected beam after the collimated laser beam is reflected by the optical surface of the object to be tested is initially in a collimated state, the optical surface of the object to be tested at the bottom of the test sample 6 needs to be precisely polished, and the surface roughness after polishing is less than or equal to 0.02 m, to achieve specular reflection.

[0043] The polarization measurement component includes a polarizer, a transmission grating group and a filter lens 11 which are arranged in sequence along the optical path direction of the laser reflected light beam; the transmission grating group includes a front polarization transmission grating and a rear polarization transmission grating, the laser reflected light beam is diffracted on the front polarization transmission grating, and the diffracted light beam passing through the front polarization transmission grating is diffracted again on the rear polarization transmission grating to form an interference light beam; the interference light beam is converged into a diffraction spot through the filter lens 11.

[0044] The polarization measurement component includes a polarizer 8, a transmission grating group and a filter lens 11 which are arranged in sequence along the optical path direction of the laser reflected light beam; the laser reflected light beam propagates to the polarizer 8 and is converted into linearly polarized light for transmission, wherein the polarizer 8 is a linear polarizer made of a dichroic material to convert the laser reflected light beam of natural light into linearly polarized light.

[0045] The transmission grating group includes a front liquid crystal polarization Ronchi transmission grating 9 and a rear liquid crystal polarization Ronchi transmission grating 10. The linearly polarized light beam is diffracted on the front polarization transmission grating, and the diffracted circularly polarized light beam passing through the front polarization transmission grating is diffracted again on the rear polarization transmission grating to form a circularly polarized light beam in an orthogonal direction, which is converged into a diffraction spot through the filter lens 11 and interfered with by the pixelated polarization camera 12 for imaging; the material of the example filter lens 11 is optical glass K9.

[0046] The front polarization transmission grating and the rear polarization transmission grating of the example are both Ronchi square wave diffraction gratings made of liquid crystal polymer, with a duty cycle of 1:1; for example, the front polarization transmission grating is the front liquid crystal polarization Ronchi transmission grating 9, and the linearly polarized light passing through the front liquid crystal polarization Ronchi transmission grating 9 is incident perpendicular to the grating plane (that is, the incident angle passing through the grating is 0 degrees). The linearly polarized light is diffracted on the front polarization transmission grating to form two circularly polarized light beams in orthogonal directions, and the diffracted circularly polarized light beams then reach the rear polarization transmission grating; the rear polarization transmission grating can be the rear liquid crystal polarization Ronchi transmission grating 10, and the diffracted circularly polarized light beams reach the rear liquid crystal polarization Ronchi transmission grating 10 and undergo a second diffraction, each forming a circularly polarized light beam in an orthogonal direction, and after passing through the rear liquid crystal polarization Ronchi transmission grating 10, they can directly reach the filter lens 11 to be converged into a diffraction spot and enter the pixelated polarization camera 12 of the image acquisition and processing system to generate an interference pattern, wherein the light path diagram of the system is as shown in FIG. Figure 2 shown.

[0047] The image acquisition and processing system is arranged downstream of the filter lens 11 along the optical path direction of the laser reflected light beam to collect the laser image diffraction spot, and perform polarization phase shift for coherent gradient sensing measurement and post-processing calculation; the image formed by the infrared thermal imaging device is processed by the image acquisition and processing system.

[0048] In this embodiment, along the optical path direction of the laser reflected light beam, the image acquisition and processing system is arranged downstream of the filter lens 11 to collect diffraction spots for polarization phase shift coherent gradient sensing measurement and post-processing calculation; at the same time, the infrared band light emitted from the optical surface is transmitted through the prism assembly to the bottom of the infrared thermal imager 13 for imaging and processed by the computer image post-processing system 14. The exemplary image acquisition and processing system includes a digital industrial polarization camera integrated with an aperture stop 1203 and an integrated computer image post-processing system 14, wherein the computer image post-processing system 14 can process the images of the digital industrial polarization camera and the infrared thermal imaging device. Among them, the digital industrial polarization camera is a pixelated polarization camera 12, that is, the lens of the pixelated polarization camera 12 of the present application is integrated with an aperture stop 1203; the interference light beam is converged into a diffraction spot and then enters the pixelated polarization camera 12 integrated with the aperture stop 1203 and interferes in front of the target, and the collected information is sent to the computer image post-processing system 14 for further calculation and post-processing.

[0049] The present application utilizes the characteristics of polarization phase shift and the characteristics of the infrared thermal imager 13, separates light of different wavelength bands through a prism component and processes the temperature field results; adjusts the polarization state of the interference light beam through a polarization measurement component and an image acquisition and processing system to obtain the spatial phase shift deformation field results. The principle is simple and the operation is convenient. It solves the technical problem of simultaneously and accurately measuring the temperature field and the deformation gradient field in real time, and expands the measurement range. In addition, the present application is suitable for real-time measurement of deformation and temperature of various optical surfaces that can reflect mirrors, and realizes the requirements of in-situ real-time multi-information measurement of industrial surfaces with high efficiency, non-destructiveness, ease of operation, and a wide range of applications.

[0050] In some embodiments, the prism assembly includes a beam splitter prism 4, a dichroic mirror 5 and a plane reflector 7; the collimated laser beam passes through the beam splitter prism 4 and the dichroic mirror 5 to enter the optical surface of the object to be measured; the laser reflected light beam is directed from the reflecting surface of the beam splitter prism 4 and the dichroic mirror 5 to the plane reflector 7 and then to the polarization measurement assembly to keep the laser reflected light beam horizontal; the infrared band light beam is split by the dichroic mirror 5 to the infrared thermal imaging device.

[0051] In the front-to-back direction, the beam splitter prism 4 is arranged between the collimating convex lens 3 and the dichroic mirror 5. The beam splitter prism 4 includes two right-angle optical quartz glass prisms, and the inclined surfaces of the two right-angle optical quartz glass prisms are bonded and coated with a semi-transparent and semi-reflective film or a dichroic film to form a reflective surface. In other words, the inclined surfaces of the two right-angle optical quartz glass prisms are bonded as follows: Figure 1As shown, the laser light passing through the collimating convex lens 3 passes through the beam splitter prism 4 and reaches the dichroic mirror 5, wherein the dichroic mirror 5 is a long-wave dichroic mirror, and the dichroic mirror 5 includes two right-angle optical quartz glass prisms, and the inclined surfaces of the two right-angle optical quartz glass prisms are bonded and coated with a semi-transparent and semi-reflective film or a dichroic film to form a reflecting surface, so the dichroic mirror 5 can reflect the reflected collimated laser beam in the visible light band, and reflect the laser reflected beam reflected by the optical surface of the object to be measured to the beam splitter prism 4; at the same time, the infrared band light beam emitted by the optical surface of the object to be measured will be transmitted through the dichroic mirror 5 and imaged on the target surface of the infrared thermal imaging device.

[0052] The laser reflected light beam reflected by the bottom optical surface of the sample to be tested 6 is then redirected to the plane reflector 7 through the beam splitter prism 4. The laser reflected light beam is reflected by the plane reflector 7, and the light path is changed to propagate in the front-back direction, wherein the material of the plane reflector 7 is optical glass K9, and a layer of reinforced aluminum reflective film is vacuum-deposited on the surface. The laser passes through the laser modulation component and the beam splitter prism 4 and is reflected by the dichroic mirror 5 to the bottom optical surface of the sample to be tested 6 and reflects. The dichroic mirror 5 reflects the nearly collimated emitted light and reaches the beam splitter prism 4 again. The beam splitter prism 4 reflects the laser reflected light beam to the plane reflector 7 for redirection, and propagates to the polarizer 8 made of dichroic material and converts the natural polarized light into linear polarized light, which is transmitted to the polarization grating group, reaches the filter lens 11 and converges into a diffraction spot and enters the image acquisition and processing system containing the pixelated polarization camera 12.

[0053] Therefore, the reflection surface of the beam splitter 4 transmits the collimated laser beam to the dichroic mirror 5, and the dichroic mirror 5 reflects the collimated laser beam onto the optical surface of the object to be tested and reflects the reflected light back to the beam splitter 4; the beam splitter 4 reflects the laser reflected beam onto the plane reflector 7; the plane reflector 7 is parallel to the reflection surface of the beam splitter 4 to turn the reflected laser beam so that the optical path direction of the reflected laser beam is consistent with the horizontal direction. Therefore, compared with the related art, the present application adds a dichroic mirror 5, and the laser reflected beam becomes a diffraction spot and enters the pixelated polarization camera 12 of the integrated aperture diaphragm 1203 to interfere with and collect the image. The collected information is connected with the infrared thermal imaging data collected by the infrared thermal imager 13 and sent to the computer image post-processing system 14 for further calculation and post-processing, so as to realize the full-field real-time measurement of the deformation and temperature of the optical surface of the object to be tested at the bottom of the test sample 6. It has a simple structure, a concise principle, and does not need to change the original coherent gradient sensing measurement system optical path arrangement, is easy to operate, and has a low economic cost for transformation.

[0054] In some embodiments, the beam expanding convex lens 2 and the collimating convex lens 3 are both disposed on a slider; the slider is adapted to a slide rail extending along the optical path direction of the collimated laser beam.

[0055] Wherein, the beam expander convex lens 2 and the collimator convex lens 3 are both arranged on a slider, and there are multiple sliders adapted to the slide rail, and the extension direction of the slide rail is the same as the direction of the collimated laser beam optical path. In this embodiment, the beam expander convex lens 2 and the collimator convex lens 3 are respectively arranged on the slider, and the slider can be moved on the slide rail to achieve the purpose of adjusting the position of the beam expander convex lens 2 and the collimator convex lens 3. For example, considering that the beam expander convex lens 2 and the collimator convex lens 3 need to be translated according to requirements to modulate the laser emitted by the single longitudinal mode laser 1, a first slide rail 204 is arranged along the front-to-back direction, and a first slider 203 and a second slider 303 are arranged on the first slide rail 204 in sequence, and the beam expander convex lens 2 is arranged on the first slider 203; the collimator convex lens 3 is arranged on the second slider 303; when it is necessary to modulate the laser according to the test requirements, the beam expander convex lens 2 and the collimator convex lens 3 are translated accordingly by the first slider 203 and the second slider 303, and it is ensured that the centers of the beam expander convex lens 2 and the collimator convex lens 3 are at the same horizontal height.

[0056] In some embodiments, all components except the computer image post-processing system 14 and the infrared thermal imaging device are integrated onto the bottom plate base by the support assembly.

[0057] In some embodiments, the system further includes a support assembly and a fixing member; the support assembly includes a plurality of supports, and all components except the infrared thermal imager 13 and the computer image post-processing system 14 are integrated onto the bottom plate base 0 through the support assembly and the fixing member.

[0058] For example, the laser modulation assembly includes a laser support 101 disposed on the bottom plate base 0, on which a single longitudinal mode laser 1 for providing a laser light source is fixedly disposed; a beam expander convex lens 2 and a collimator convex lens 3 are connected at the same horizontal plane height along the optical path through a first slide rail 204. A beam splitter prism support 401 for fixing and placing a beam splitter prism 4 is disposed on the bottom plate base 0. After the beam splitter prism support 401 raises the horizontal height of the beam splitter prism 4, it is ensured that the laser modulated by the laser modulation assembly can completely pass through the beam splitter prism 4. In some schemes, in order to fix the beam expander convex lens 2 and the collimator convex lens 3, a beam expander support 202 is disposed on the first slider 203, and the beam expander convex lens 2 is fixedly disposed on the beam expander frame 201 at the top of the beam expander support 202, and a collimator support 302 is disposed on the second slider 303, and the collimator convex lens 3 is fixedly disposed on the collimator frame 301 at the top of the collimator support 302.

[0059] For another example, the bottom plate base 0 is provided with a front grating support 902 and a rear grating support 1002 for fixing the front liquid crystal polarization Ronchi transmission grating 9 and the rear liquid crystal polarization Ronchi transmission grating 10, respectively. The front grating support 902 is fixedly provided with a front grating clamping frame 901 for clamping the front liquid crystal polarization Ronchi transmission grating 9, and the rear grating support 1002 is provided with a rear grating clamping frame 1001 for clamping the rear liquid crystal polarization Ronchi transmission grating 10. The polarizer 8 is fixed on the polarizer support 802 via a polarizer frame 801. The light on the surface of the specimen can reach the filter lens 11 after being diffracted twice by the front liquid crystal polarization Ronchi transmission grating 9 and the rear liquid crystal polarization Ronchi transmission grating 10, and converges into a diffraction spot and enters the image acquisition and processing system containing the pixelated polarization camera 12.

[0060] In addition, a connecting plate 1103 is provided on the bottom plate base 0, a filter lens support 1102 for fixing the filter lens 11 is fixedly provided on the connecting plate 1103, a filter lens frame 1101 installed on the top thereof is used to install the filter lens 11, a second slide rail 1205 is fixedly provided on the connecting plate 1103, a one-dimensional pitching platform 1202 is slidably connected to the second slide rail 1205 via a third slider 1204, a camera support 1201 is fixedly provided on the one-dimensional pitching platform 1202, and the camera support 1201 is fixedly connected to the pixelated polarization camera 12 of the integrated aperture diaphragm 1203. Special are the dichroic mirror bracket 501 and the dichroic mirror support 502; wherein the dichroic mirror support 502 is provided in the sample workbench 15, and is fixedly connected to the measurement environment via a magnetic base (not marked here, and does not affect the analysis), in order to ensure that each outer surface of the dichroic mirror is parallel to each outer surface of the beam splitter prism. The dichroic mirror bracket 501 is connected to the dichroic mirror support 502 for fixing the dichroic mirror. Figure 3 shown.

[0061] It should be noted that the wavelength limit of each optical element and the surface to be measured in the system should be matched with the monochromatic laser light source emitted by the single longitudinal mode laser 1, and the laser support 101, the beam expander support 202, the first slider 203, the first slide rail 204, the collimator support 302, the second slider 303, the beam splitter prism support 401, the dichroic mirror support 501, the dichroic mirror support 502, the sample workbench 15, the plane reflector support 701, the front light The materials used for the grating clamping frame 901, the rear grating clamping frame 1001, the connecting plate 1103, the camera support 1201, and the one-dimensional pitch platform 1202 are all 304 stainless steel, and the surfaces of the first slider 203, the first slide rail 204, the second slider 303, the front grating clamping frame 901, the rear grating clamping frame 1001, the connecting plate 1103, the one-dimensional pitch platform 1202, the third slider 1204, and the second slide rail 1205 are all treated with black oxidation.

[0062] According to the second aspect, the present application proposes a method for high-precision synchronous real-time measurement of temperature field and deformation field, which uses the system in any of the above embodiments to perform measurement, including the following steps:

[0063] S1: Building a system in any of the above embodiments;

[0064] S2: Reasonably set the parameters of the infrared thermal imaging device according to the thermal radiation characteristics of the optical surface of the object to be measured, so that the surface temperature value obtained by the infrared thermal imaging device is consistent with the optical surface temperature of the object to be measured;

[0065] S3: adjusting the laser modulation component according to the characteristics of the optical surface of the object to be measured, the light modulation component emits a collimated laser beam and incidents on the optical surface of the object to be measured through the prism component; the laser reflected beam reflected by the optical surface of the object to be measured is in a collimated state; at the same time, the infrared band beam emitted by the optical surface of the object to be measured is transmitted through the prism component to the infrared thermal imaging device for imaging;

[0066] S4: adjusting the clamping state of the polarization measurement assembly so that the grating lines of the front polarization transmission grating and the rear polarization transmission grating are parallel to each other;

[0067] S5: The image acquisition and processing system acquires the laser image diffraction spot and the infrared thermal image data of the infrared thermal imaging device, and performs polarization phase shift coherent gradient sensing measurement and post-processing calculation on the laser image diffraction spot.

[0068] Among them, build Figure 1 The system shown in the figure comprises a bottom plate base 0, on which a laser modulation component is arranged; wherein the beam splitter prism 4 can reflect the laser reflection light beam of the optical surface of the test sample 6 to be tested object reflected by the long-wave pass dichroic mirror 5 to the plane reflector 7, wherein the roughness of the optical surface of the test object is not greater than 0.02 μm; at the same time, the long-wave pass dichroic mirror 5 transmits the infrared band light emitted by the bottom optical surface of the test sample 6 to the infrared thermal imager 13 and forms an image; the plane reflector 7 redirects the reflected laser beam to the polarizer 8; along the front-to-back direction, a transmission grating group is arranged behind the polarizer 8, and a filter lens 11 is arranged behind the transmission grating group; correspondingly, a pixelated polarization camera 12 is arranged behind the filter lens 11 along the optical path direction to realize spatial phase shift and image acquisition. Among them, the polarizer 8 converts the laser reflected beam of natural light into linearly polarized light; the transmission grating group includes a front polarization transmission grating and a rear polarization transmission grating; the front polarization transmission grating and the rear polarization transmission grating are both transmission liquid crystal polymer diffraction gratings with a line density of 20 lines / mm.

[0069] After building a synchronous real-time measurement device for temperature field and deformation field based on coherent gradient sensing and infrared thermal imaging technology, adjust the positions of the beam expanding convex lens 2, the collimating convex lens 3, the beam splitting prism 4 and the dichroic mirror 5 on the optical axis and the pitch angle of the sample workbench 15 according to the characteristics of the optical surface of the test sample 6 and the object to be tested, so that the light beam reflected by the bottom optical surface of the test sample 6 is in a collimated state; the sample workbench 15 is a processing platform set up to facilitate manufacturing and processing in environments such as laser directional energy deposition. The clamping state of the front polarization transmission grating and the rear polarization transmission grating is adjusted so that the grating lines of the two gratings in two directions are parallel to each other; the parameters of the infrared thermal imager 13 are adjusted so that the target surface of the infrared thermal imager 13 is orthogonal to the extension direction of the collimated light beam reflected by the optical surface of the object to be measured, so that the infrared thermal imaging result of the infrared thermal imager 13 on the optical surface of the object to be measured is a real result; at the same time, the target surface of the digital industrial polarization camera is orthogonal to the extension direction of the collimated laser beam, and the pixelated polarization camera 12 with the integrated aperture diaphragm 1203 is opened and the infrared thermal imager 13 starts to collect data synchronously, and the deformation gradient field and temperature field are further measured and post-processed by the computer image post-processing system 14; wherein the polarization directions of the target surface super-pixels of the digital industrial polarization camera are 0°, 45°, 90°, 135° from left to right and from top to bottom in a clockwise direction, respectively. Figure 4 shown.

[0070] It should be noted that, in the description of this application, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. In addition, in the description of this application, unless otherwise specified, the meaning of "plurality" is two or more.

[0071] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, segment or portion of code that includes one or more executable instructions for implementing the steps of a specific logical function or process, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in the reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present application belong.

[0072] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0073] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A system for high-precision synchronous real-time measurement of temperature field and deformation field, characterized in that: include A laser modulation component, wherein the collimated laser beam emitted by the laser modulation component is incident on the optical surface of the object to be measured through the prism component; the laser reflected beam in the visible light band reflected by the optical surface of the object to be measured is in a collimated state and is reflected to the polarization measurement component through the prism component; the infrared band beam emitted by the optical surface of the object to be measured is transmitted through the prism component to the infrared thermal imaging device for imaging; The polarization measurement component comprises a polarizer, a transmission grating group and a filter lens which are sequentially arranged along the optical path direction of the laser reflected light beam; the transmission grating group comprises a front polarization transmission grating and a rear polarization transmission grating, the laser reflected light beam is diffracted on the front polarization transmission grating, and the diffracted light beam passing through the front polarization transmission grating is diffracted again on the rear polarization transmission grating to form an interference light beam; the interference light beam is converged into a diffraction spot through the filter lens; and An image acquisition and processing system is arranged downstream of the filter lens along the optical path direction of the laser reflected light beam, and is used to acquire the laser image diffraction spot and perform polarization phase shift to perform coherent gradient sensing measurement and post-processing calculation; the image formed by the infrared thermal imaging device is processed by the image acquisition and processing system.

2. The system according to claim 1, characterized in that The prism assembly includes a beam splitter, a dichroic mirror and a plane reflector; the collimated laser beam is incident on the optical surface of the object to be measured through the beam splitter and the dichroic mirror; the laser reflected light beam is directed from the reflective surface of the beam splitter and the dichroic mirror to the plane reflector and then to the polarization measurement assembly to keep the laser reflected light beam horizontal; the infrared band light beam is split by the dichroic mirror and transmitted to the infrared thermal imaging device.

3. The system according to claim 2, characterized in that The laser modulation assembly comprises a laser for providing laser light, and a beam expanding convex lens and a collimating convex lens which are sequentially arranged along the optical path direction of the collimated laser beam.

4. The system according to claim 3, characterized in that The beam expanding convex lens and the collimating convex lens are both plano-convex lenses and are both arranged on a slider; the slider is adapted to a slide rail extending along the optical path direction of the collimated laser beam.

5. The system according to claim 2, characterized in that The dichroic mirror is a long-wave pass dichroic mirror, so as to allow the infrared band light beam to be transmitted and imaged on the target surface of the infrared thermal imaging device; and simultaneously reflect the collimated laser beam.

6. The system according to any one of claims 2 to 5, characterized in that: The reflective surfaces of the beam splitter prism and the dichroic mirror each include two right-angle optical quartz glass prisms, and the inclined surfaces of the two right-angle optical quartz glass prisms are bonded and coated with a semi-transparent and semi-reflective film or a dichroic film to form the reflective surface.

7. The system according to claim 6, characterized in that The polarizer is a linear polarizer made of a dichroic material to convert the laser reflected light beam of natural light into linear polarized light.

8. The system according to claim 6, characterized in that The front polarization transmission grating and the rear polarization transmission grating are both transmission-type Ronchi square-wave diffraction gratings made of liquid crystal polymer; the duty ratio of the transmission-type Ronchi square-wave diffraction grating is 1:

1.

9. The system according to claim 1, characterized in that The image acquisition and processing system comprises a digital industrial polarization camera integrated with an aperture stop and a computer image post-processing system.

10. The system according to claim 9, characterized in that All components except the computer image post-processing system and the infrared thermal imaging device are integrated onto the bottom plate base by a supporting assembly.

11. A method for high-precision synchronous real-time measurement of temperature field and deformation field, characterized in that: Measuring using the system described in any one of claims 1 to 10 comprises the following steps: Constructing a system as described in any one of claims 1 to 10; Reasonably set the parameters of the infrared thermal imaging device according to the thermal radiation characteristics of the optical surface of the object to be measured, so that the surface temperature value obtained by the infrared thermal imaging device is consistent with the optical surface temperature of the object to be measured; The laser modulation component is adjusted according to the characteristics of the optical surface of the object to be measured, and the laser modulation component emits a collimated laser beam and is incident on the optical surface of the object to be measured through a prism component; the laser reflected light beam reflected by the optical surface of the object to be measured is in a collimated state; at the same time, the infrared band light beam emitted by the optical surface of the object to be measured is transmitted through the prism component to the infrared thermal imaging device for imaging; Adjusting the clamping state of the polarization measurement assembly so that the grating lines of the front polarization transmission grating and the rear polarization transmission grating are parallel to each other; The image acquisition and processing system acquires the image data of the laser image diffraction spot and the infrared thermal imaging device, and performs polarization phase shift coherence gradient sensing measurement and post-processing calculation on the laser image diffraction spot.

12. The method according to claim 11, characterized in that The surface roughness of the optical surface of the object to be measured after polishing is less than or equal to 0.02 μm.

13. The method according to claim 11, characterized in that The target surface imaged by the infrared thermal imaging device is orthogonal to the extension direction of the collimated light beam reflected by the optical surface of the object to be measured; the target surface of the digital industrial polarization camera is orthogonal to the extension direction of the interference light beam.

14. The method according to claim 13, characterized in that The polarization directions of the target surface superpixels of the digital industrial polarization camera are 0°, 45°, 90°, and 135° from left to right and from top to bottom in a clockwise direction.

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