Curved surface temperature and deformation detection method and device based on digital light

Abstract

The invention discloses a curved surface temperature and deformation detection method and device based on digital light, and relates to the technical field of non-contact optical measurement, and the method comprises the steps: S11, carrying out the temperature calibration, and obtaining a fitting function of the phosphorescence lifetime and the temperature; s12, projecting a periodic signal combined by a phosphorescence excitation signal and a surface structure light signal to the three-dimensional structure sample coated with the phosphorescence coating by a projector to generate reflected light of surface structure light and phosphorescence return light; s13, acquiring an image of phosphorescent return light by using the first camera, and measuring temperature information of each coordinate point from the image based on a fitting function of phosphorescent lifetime and temperature; s14, acquiring an image of reflected light of the surface structured light by using a second camera, and measuring depth information of each coordinate point from the image; and S15, combining the depth information and the temperature information to construct a three-dimensional temperature field. According to the invention, three-dimensional temperature field reconstruction is realized by combining a phosphorescence lifetime temperature measurement technology and a structured light technology, three-dimensional deformation measurement can be carried out at the same time, and the cost is reduced while the measurement precision is effectively improved.

Description

Technical Field

[0001] The present invention relates to the technical field of non-contact optical measurement, and in particular to a method and device for detecting curved surface temperature and deformation based on digital light. Background Art

[0002] In the face of extremely harsh environments such as high temperature, high pressure, and high speed in the future, in order to ensure the performance of aircraft engines, more comprehensive structural strength design and working performance testing are very necessary during the development process. Before that, it is a big problem to obtain various information data of aircraft engines through reliable and accurate testing technology. Among them, the temperature distribution detection of the engine blade surface and the detection of its deformation field are the problems that need to be solved.

[0003] At present, the temperature measurement methods on the surface of aircraft engine blades are mainly divided into contact temperature measurement and non-contact temperature measurement. Contact temperature measurement mainly includes thermocouple temperature measurement, temperature indicating paint temperature measurement and crystal temperature measurement; non-contact temperature measurement mainly includes infrared radiation temperature measurement, phosphorescence temperature measurement, optical fiber temperature measurement, etc. Compared with the traditional contact temperature measurement method, phosphorescence temperature measurement has obvious advantages: non-contact temperature measurement path, high temperature measurement accuracy, not easily affected by the environment, low cost of use, etc., and the traditional temperature measurement method has reached the bottleneck of development, and phosphorescence temperature measurement has great potential in the future. At present, the surface of aircraft engine blades is a three-dimensional curved surface, and the single-point and two-dimensional phosphorescence temperature measurement solutions are relatively mature, but there is still a certain gap with the requirements of actual three-dimensional curved surface temperature measurement applications.

[0004] Optical 3D measurement technology includes passive measurement technology and active measurement technology. Passive measurement refers to the method of reconstructing the surface of an object directly through the image taken by the camera without the help of a designed light source. Passive measurement can be divided into monocular vision method and multi-eye vision method according to the number of image viewing angles used. Active measurement method refers to the method of projecting the designed light source signal to the object to be measured and receiving the signal back at the same time. Then compare the signal difference to obtain the depth information of the object for effective 3D reconstruction and measurement. According to the different principles of the method, active measurement methods can be divided into three categories: laser ranging-based methods, signal interference-based methods, and structured light-based methods. Among them, the structured light-based method is the most widely used, and it has good compatibility with phosphorescence measurement technology, so it is more feasible to combine the two. There are six modulation methods of structured light in the structured light-based method: interference fringe projection method, physical grating projection method, optical mask projection method, diffraction fringe projection method, digital light processing projection method, and MEMS projection method. Each modulation method has its own advantages and disadvantages, but compared with other modulation methods, digital light processing projection method and MEMS projection method have better performance. Both have advantages such as programmability and high-quality projection, but the latter is still immature in application. Therefore, it is currently a better solution to use digital light processing projection method for structured light modulation effect.

[0005] In the current phosphorescence temperature measurement technology, due to the influence of factors such as uneven phosphorescence smearing, poor directionality of excited phosphorescence and environment, the intensity method and the intensity ratio method have large errors in two-dimensional / three-dimensional measurement, while the phosphorescence lifetime method is not affected by the above factors and has greater advantages in two-dimensional / three-dimensional measurement; and the optical three-dimensional measurement technology used in three-dimensional temperature measurement can also be used in the detection of three-dimensional shape changes, so the combination of the two can effectively reduce costs; therefore, in order to solve the problems of three-dimensional temperature measurement and three-dimensional deformation detection on the surface of aircraft engine blades, this field urgently needs a solution that can simultaneously realize the testing of both. Summary of the invention

[0006] In response to the above problems, the present invention proposes a surface temperature and deformation detection method and device based on digital light. By combining the phosphorescence lifetime temperature measurement technology with the structured light three-dimensional reconstruction method, the reconstruction of the three-dimensional temperature field and the measurement of the three-dimensional deformation are realized. The device is simple to build and has complete functions. It can effectively improve the measurement accuracy, that is, the anti-interference ability, and reduce the cost. It can be flexibly used in scenarios where surface temperature measurement and deformation measurement are required.

[0007] On the one hand, a surface temperature detection method based on digital light, the specific steps are as follows:

[0008] S11, performing temperature calibration to obtain a fitting function of phosphorescence lifetime and temperature;

[0009] S12, applying simulated environmental conditions so that the three-dimensional structure sample coated with the phosphorescent coating is in the simulated environment; a projector projects a periodic signal of a surface structured light signal combined with a phosphorescent excitation signal onto the three-dimensional structure sample coated with the phosphorescent coating, generating reflected light of the structured light under the simulated environment and phosphorescent return light;

[0010] S13, using the first camera to collect an image of phosphorescent return light, and measuring the temperature information of each coordinate point in the image of phosphorescent return light based on the fitting function;

[0011] S14, using a second camera to collect an image of the reflected light of the surface structured light, and based on a surface structured light three-dimensional measurement method, detecting depth information of each coordinate point from the image of the reflected light of the surface structured light to obtain first depth information;

[0012] S15, combining the first depth information and the temperature information to construct a three-dimensional temperature field and obtain the phosphorescent surface temperature.

[0013] Preferably, the periodic signal of the surface structured light signal combined with the phosphorescence excitation signal is as follows:

[0014] Each period of the periodic signal is formed by segmented combination of a phosphorescence excitation signal and a structured light signal; the phosphorescence excitation signal is a square wave light signal; and the surface structured light signal is a sinusoidal grating structured light.

[0015] Preferably, the temperature calibration is performed using a two-dimensional plane plate coated with a phosphorescent coating; the coating technology of the two-dimensional plane plate coated with the phosphorescent coating and the three-dimensional structure sample coated with the phosphorescent coating is the Weissenberg direct writing technology.

[0016] Preferably, in S13, the first camera is used to collect an image of phosphorescence return light, and the temperature information of each coordinate point in the image of phosphorescence return light is measured based on a fitting function of phosphorescence lifetime and temperature, as follows:

[0017] The phosphorescence lifetime value corresponding to each coordinate is solved based on the three-frame method and the phosphorescence lifetime decay equation, and the phosphorescence lifetime value corresponding to each coordinate is substituted into the phosphorescence lifetime and temperature fitting curve function to obtain the temperature information corresponding to each coordinate.

[0018] Preferably, in S14, the image of the reflected light of the surface structured light is collected by the second camera, and the depth information of each coordinate point in the image of the reflected light of the surface structured light is measured based on the surface structured light three-dimensional measurement method, specifically as follows:

[0019] The second camera collects the reflected light of the surface structured light to obtain a reflected light image of the surface structured light corresponding to each phase difference value;

[0020] The phase shift method is used to extract the phase, and the package phase and modulation value corresponding to each coordinate point are obtained;

[0021] The phase values ​​of all coordinate points are unfolded by the phase fast unfolding method;

[0022] The depth information of each coordinate point is obtained by reconstructing the Thornwell wavefront model.

[0023] Preferably, in S15, the combining of the first depth information and the temperature information to construct a three-dimensional temperature field is as follows:

[0024] Match the depth information of each coordinate point in the image of structured light reflection light with the corresponding plane coordinate point in the temperature information of each coordinate point in the image of phosphorescent return light, obtain the depth information and temperature information under the same plane coordinates, display the coordinate information, depth information and temperature information in the same coordinate axis system, and finally obtain the three-dimensional temperature field based on the point cloud three-dimensional reconstruction technology.

[0025] On the other hand, a deformation detection method based on digital light is provided, which is based on a curved surface temperature detection method based on digital light, and includes:

[0026] S21, without applying a simulated environment condition, a periodic signal combining a surface structured light signal and a phosphorescence excitation signal is projected by a projector onto a three-dimensional structured sample coated with a phosphorescent coating, thereby generating reflected light of the structured light under a non-simulated environment;

[0027] S22, using a second camera to collect an image of the reflected light of the surface structured light, and measuring the depth information of each coordinate point in the image of the reflected light of the surface structured light based on a surface structured light three-dimensional measurement method to obtain second depth information;

[0028] S23, reconstructing the first depth information and the second depth information in three dimensions in the same coordinate axis, and calculating a three-dimensional shape variable.

[0029] In yet another aspect, a curved surface temperature and deformation detection device based on digital light includes a projector, a dichroic mirror, a first lens, a first camera, a second camera, a second lens, a control system, a temperature controller, and a heat stage;

[0030] The projector receives the light code generated by the control system, generates and projects the corresponding projection light to the dichroic mirror;

[0031] The dichroic mirror allows the projection light projected from the projector to be vertically projected through the top of the hot stage and projected onto the three-dimensional structure sample coated with the phosphorescent coating placed on the hot stage; the return light of the three-dimensional structure sample coated with the phosphorescent coating enters the second narrow light filter and enters the first narrow light filter through the dichroic mirror;

[0032] The first narrow-band filter separates phosphorescence information in a specific wavelength range from the return light of the three-dimensional structure sample coated with the phosphorescent coating; the return light of the three-dimensional structure sample coated with the phosphorescent coating passes through the first narrow-band filter, the first lens and the first camera in sequence, and an image of the phosphorescent return light is generated and transmitted to the control system; the first camera is a high-speed camera;

[0033] The second narrow-band filter separates structured light information in a specific wavelength range from the return light of the three-dimensional structure sample coated with the phosphorescent coating; the return light of the three-dimensional structure sample coated with the phosphorescent coating passes through the second narrow-band filter, the second lens and the second camera in sequence to generate an image of the reflected light of the surface structured light and transmit it to the control system; the second camera is a CCD camera or a CMOS camera;

[0034] The hot stage is used to fix the three-dimensional structure sample or calibration plate coated with the phosphorescent coating; the temperature controller is used to control the change of the temperature of the hot stage;

[0035] The control system generates light coding and controls the projection of the projector; is connected to a temperature controller connected to the heat stage to control the temperature of the heat stage; receives and processes image information from the first camera and the second camera and synthesizes a three-dimensional temperature field.

[0036] Preferably, the projector uses DLP digital light processing technology for projection.

[0037] Compared with the prior art, the present invention has the following beneficial effects:

[0038] (1) The present invention realizes the reconstruction of three-dimensional temperature field and the measurement of three-dimensional deformation by combining phosphorescence lifetime temperature measurement technology with structured light three-dimensional reconstruction method. The device is simple to build and has complete functions. It can effectively improve the measurement accuracy, that is, the anti-interference ability, and reduce the cost. It can be flexibly used in scenes where curved surface temperature measurement and deformation measurement are required.

[0039] (2) The present invention uses a DLP projector for projection, which can adjust the intensity of the structured light and avoid the influence of oversaturation on three-dimensional reconstruction; the present invention uses the same projection light for phosphorescence lifetime temperature measurement and structured light measurement, which basically do not interfere with each other, reducing the construction cost while maintaining the accuracy level of the original technologies.

[0040] (3) The present invention uses phosphorescence temperature method to measure temperature, without considering the problems of shape change and uneven phosphorescence coating, and has higher measurement accuracy than other phosphorescence temperature measurement methods; the present invention uses phase decoding to obtain depth information, which has higher measurement accuracy; BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The present invention is further described in detail below in conjunction with the accompanying drawings;

[0042] Figure 1 is a schematic diagram of a curved surface temperature and deformation detection device based on digital light according to an embodiment of the present invention;

[0043] Figure 2 is a flow chart of a curved surface temperature detection method based on digital light according to an embodiment of the present invention;

[0044] Figure 3 A schematic diagram of the flow of a curved surface temperature detection method based on digital light and a deformation detection method based on digital light according to an embodiment of the present invention;

[0045] Description of the drawings: 1. DLP digital projector; 2. Dichroic mirror; 3. First narrow-band filter; 4. First lens; 5. First industrial camera; 6. Second industrial camera; 7. Second lens; 8. Second narrow-band filter; 9. Computer; 10. Temperature controller; 11. Hot stage; 12. Three-dimensional structure sample coated with phosphorescent coating. DETAILED DESCRIPTION

[0046] The present invention is further described below through specific implementation modes.

[0047] See also Figure 1 As shown, a curved surface temperature and deformation detection device based on digital light according to an embodiment of the present invention includes a DLP digital projector 1; a dichroic mirror 2; a first narrow-band filter 3; a first lens 4; a first industrial camera 5; a second industrial camera 6; a second lens 7; a second narrow-band filter 8; a computer 9; a temperature controller 10; a heat stage 11; and a three-dimensional structure sample 12 coated with a phosphorescent coating.

[0048] The DLP digital projector 1 receives the light encoding generated by the algorithm of the computer 9, and emits a periodic light signal composed of a square wave light signal and a sinusoidal grating structure light signal. The periodic light signal emitted by it is reflected by the dichroic mirror 2 onto the surface of the three-dimensional structure sample 12 coated with a phosphor coating in the hot stage 11; the dichroic mirror 2 is installed at a horizontal angle of 45°, with the reflective surface vertically facing the DLP digital projector 1 and the transmissive surface vertically facing the window directly above the hot stage 11.

[0049] The hot stage 11 and its matching temperature controller 10 are used to control the temperature change and fix the three-dimensional structure sample or calibration plate coated with the phosphorescent coating. The temperature control range is from room temperature to 1000°C, and the temperature control accuracy is 0.1°C. The temperature of the hot stage 11 is controlled by the temperature controller 10, and the temperature controller 10 is connected to the computer 9 to control and detect the temperature at this time on the computer 9.

[0050] The phosphorescence signal excited on the three-dimensional structure sample 12 coated with the phosphorescent coating is emitted to the first industrial camera 5 via the dichroic mirror 2, the first narrow-band filter 3 and the first lens 4; wherein the central wavelength of the first narrow-band filter 3 is 610nm, the first industrial camera 5 is a high-speed camera, and the first industrial camera 5 only stores a number of phosphorescence images excited by the square wave light signal;

[0051] The light signal reflected from the surface of the three-dimensional structure sample 12 coated with the phosphorescent coating is emitted to the second industrial camera 6 via the second narrow-band filter 8 and the second lens 7; wherein the central wavelength of the second narrow-band filter 8 is 405nm, the second industrial camera 6 is an ordinary CCD camera or CMOS camera, and the second industrial camera 6 only saves four return light images reflected from the sinusoidal grating structure light signal.

[0052] Finally, computer 9 is used as a control system. All images are analyzed and processed by computer 9, and the three-dimensional temperature field is reconstructed and the three-dimensional deformation variable is calculated by the algorithm on computer 9. It also includes controlling the projection of DLP digital projector, the temperature change of the heating stage and its matching temperature controller, and the information reception and processing of industrial camera.

[0053] Specifically, the wavelength of the projection light of the DLP digital projector is 405nm; the first industrial camera 5 and the second industrial camera 6 have the same resolution, and the optical path for receiving light information remains basically the same; the half-wave bandwidths of the first narrow-band filter 3 and the second narrow-band filter 8 are both 10nm; the dichroic mirror 2 is used for optical path transmission, so that the surface structured light generated by the DLP digital projector 1 is projected vertically above the heat stage or the industrial camera can receive the return light returned from above the heat stage.

[0054] See also Figure 2 As shown, a curved surface temperature detection method based on digital light in an embodiment of the present invention is specifically as follows:

[0055] S11, performing temperature calibration to obtain a fitting function of phosphorescence lifetime and temperature.

[0056] Before temperature calibration, perform camera calibration and projector calibration first.

[0057] The camera calibration method is one of the Zhang Zhengyou calibration method, the phase shift grating calibration method, etc., so as to obtain the internal and external parameters of the camera. The calibration plate used is one of the checkerboard, the circular array, the single concentric circle grating, etc. The calibration plate of this embodiment uses a checkerboard; after the camera is calibrated, the internal and external parameters of the camera are obtained.

[0058] The projector calibration is performed after the camera calibration, and the calibration method used is one of the reverse camera method and the pseudo camera method, so as to obtain the internal and external parameters of the projector. The projector calibration of this embodiment adopts the camera method, and the calibration board used is a chessboard board. After the projector calibration, the internal and external parameters of the projector are obtained.

[0059] The specific steps of temperature calibration are as follows:

[0060] S111, the calibrated first industrial camera 5, the second industrial camera 6 and the DLP digital projector 1 are installed on the measuring platform, and a two-dimensional plane plate coated with a mixture of Y2O3:Eu phosphor and PDC ceramic is placed inside the hot stage 11, and the coating technology used is the Weissenberg direct writing technology. The periodic light signal generated by the algorithm on the computer 9 is encoded and transmitted to the DLP digital projector 1, so that the DLP digital projector 1 projects the periodic light signal. The front part of each period of the periodic light signal is a square wave light signal, and the rear part is a surface structure light signal, wherein the surface structure light signal is selected as a sinusoidal grating structured light, and the method of projecting the grating selects the phase shift method, the frequency of the sinusoidal grating is selected as 60Hz, and a four-step phase shift grating is generated, and the phases are π / 2, π, 3π / 2, and 2π respectively. In the temperature calibration process, only the phosphorescence information excited by the square wave light signal needs to be recorded.

[0061] It should be noted that the periodic optical signal may adopt a planar structured optical signal in the front part of each period and a square wave optical signal in the rear part of each period, and this embodiment does not impose any limitation thereto.

[0062] S112, the square wave light signal projected by the DLP digital projector 1 is irradiated onto the two-dimensional plane plate coated with the phosphorescent coating, thereby stimulating the phosphorescent signal, and then the first industrial camera 5 records multiple phosphorescent images in several time periods, that is, the phosphorescent lifetime is measured using the three-frame method, and then the phosphorescent lifetime is measured according to the attenuation equation of the phosphorescent under the pulsed excitation light. The corresponding combination relationship between phosphorescence lifetime and temperature is obtained; among them, I0 represents the initial phosphorescence intensity; t represents the time; τ represents the phosphorescence lifetime; I1 represents the constant term.

[0063] S113, controlling the temperature change of the heat stage 11 at a certain temperature interval. In this embodiment, the temperature of the heat stage 11 is controlled to change from room temperature to 1000°C at an interval of 50°C. Then, at each temperature point, the phosphorescence image group at each temperature point is operated as in step S112, and finally a fitting curve of phosphorescence lifetime and temperature is obtained, thereby obtaining a fitting curve function of phosphorescence lifetime and temperature.

[0064] S12, applying simulated environmental conditions so that the three-dimensional structure sample coated with the phosphorescent coating is in a simulated environment; the projector projects a periodic signal combining the surface structured light signal and the phosphorescent excitation signal onto the three-dimensional structure sample coated with the phosphorescent coating, generating reflected light of the structured light and phosphorescent return light under the simulated environment.

[0065] The calibrated first industrial camera 5 , second industrial camera 6 and DLP digital projector 1 are placed inside the hot stage 11 with a three-dimensional structure sample 12 coated with a phosphorescent coating.

[0066] Air flow is introduced into the hot stage 11 and the pressure is increased to create a measurement simulation environment.

[0067] The periodic light signal generated by the algorithm on the computer 9 is encoded and transmitted to the projector, so that the DLP digital projector 1 projects the periodic light signal. The front part of each period of the periodic light signal is a square wave light signal, and the rear part is a surface structured light signal, wherein the surface structured light signal is selected as a sinusoidal grating structured light, and the method of projecting the grating is a phase shift method, the frequency of the sinusoidal grating is 60Hz, and a four-step phase shift grating is generated, and the phases are π / 2, π, 3π / 2, and 2π respectively.

[0068] S13, using the first camera to collect an image of the phosphorescence return light, and measuring the temperature information of each coordinate point in the image of the phosphorescence return light based on the fitting function.

[0069] The square wave light signal projected by the DLP digital projector 1 is irradiated onto the three-dimensional structure sample 12 coated with the phosphorescent coating, thereby stimulating the phosphorescent signal. Then, the first industrial camera 5 records multiple phosphorescent images in several time periods, that is, the phosphorescent lifetime is measured using the three-frame method. Then, according to the phosphorescent lifetime decay equation The phosphorescence lifetime value corresponding to each coordinate is solved, and finally substituted into the phosphorescence lifetime-temperature fitting curve function obtained by temperature calibration to obtain the temperature information corresponding to each coordinate.

[0070] S14, using a second camera to collect an image of the reflected light of the surface structured light, and based on a surface structured light three-dimensional measurement method, detecting depth information of each coordinate point from the image of the reflected light of the surface structured light to obtain first depth information.

[0071] Specifically, the second industrial camera 6 collects the reflected light of the three-dimensional structure sample 12 coated with the phosphorescent coating generated by the partial sinusoidal grating structure light after the period, and obtains the reflected light image corresponding to each phase difference value, a total of 4 images; then the phase is extracted by the phase shift method to obtain the wrapped phase and modulation value corresponding to each coordinate point or pixel point; then the phase values ​​of all coordinates are expanded by the phase rapid expansion method; then the Southwell wavefront reconstruction model is used to obtain the depth information (height value) of each coordinate point, and the first depth information is obtained.

[0072] S15, combining the first depth information and the temperature information to construct a three-dimensional temperature field and obtain the phosphorescent surface temperature.

[0073] The temperature information corresponding to each coordinate in the image of the phosphorescent return light in step S13 is matched with the depth information (i.e., the first depth information) of each coordinate point in the image of the structured light reflected light in step S14, and then the corresponding matching relationship between the coordinates of the two is obtained, thereby obtaining the temperature information and depth information corresponding to the same coordinate, and finally obtaining the three-dimensional temperature field based on the three-dimensional reconstruction of the point cloud.

[0074] The embodiment of the present invention adopts a DLP projector for projection, which is codable and flexible. The embodiment of the present invention uses the same projection light for phosphorescence lifetime temperature measurement and structured light measurement, which basically do not interfere with each other, thereby reducing the construction cost while maintaining the accuracy level of the original technologies.

[0075] The embodiment of the present invention adopts the phosphorescence temperature method to measure temperature, without considering problems such as shape change and uneven phosphorescence coating, and has higher measurement accuracy than other phosphorescence temperature measurement methods; this embodiment adopts phase decoding to obtain depth information, and has higher measurement accuracy.

[0076] In another embodiment, deformation detection is performed simultaneously with the construction of the three-dimensional temperature field, see Figure 3 The steps of the basic implementation method are the same, the difference lies in the additional steps performed, and the specific additional steps are as follows:

[0077] S21, no simulated environmental conditions are applied; the projector projects a periodic signal combining a surface structured light signal and a phosphorescent excitation signal onto a three-dimensional structured sample coated with a phosphorescent coating, generating reflected light of the structured light under a non-simulated environment;

[0078] S22, using a second camera to collect an image of the reflected light of the surface structured light, and measuring the depth information of each coordinate point in the image of the reflected light of the surface structured light based on a surface structured light three-dimensional measurement method to obtain second depth information (or initial depth information);

[0079] S23, performing three-dimensional reconstruction on the first depth information and the second depth information in the same coordinate axis (ie, initial three-dimensional contour reconstruction and three-dimensional contour reconstruction of the test point), and calculating the three-dimensional shape variable.

[0080] Specifically, the 3D reconstruction used adopts an ICP (Iterative Closest Point) point cloud 3D reconstruction algorithm.

[0081] The embodiment of the present invention adopts a DLP projector for projection, which can adjust the intensity of structured light and avoid the influence of oversaturation on three-dimensional reconstruction; the embodiment of the present invention uses the same projection light for three-dimensional reconstruction and temperature measurement, and the two technologies do not interfere with each other; three-dimensional deformation detection is performed while reconstructing the three-dimensional temperature field, which can effectively reduce costs.

[0082] The above is only a specific implementation of the present invention, but the design concept of the present invention is not limited thereto. Any non-substantial changes to the present invention using this concept shall be deemed as an infringement of the protection scope of the present invention.

Claims

1. A curved surface temperature detection method based on digital light, characterized in that: The following steps are included: S11, performing temperature calibration to obtain a fitting function of phosphorescence lifetime and temperature; S12, applying simulated environmental conditions so that the three-dimensional structure sample coated with the phosphorescent coating is in the simulated environment; The projector projects a periodic signal combining a surface structured light signal and a phosphorescence excitation signal onto a three-dimensional structured sample coated with a phosphorescent coating, thereby generating reflected light of the structured light and phosphorescence return light in a simulated environment; S13, using the first camera to collect an image of phosphorescent return light, and measuring the temperature information of each coordinate point in the image of phosphorescent return light based on the fitting function; S14, using a second camera to collect an image of the reflected light of the surface structured light, and based on a surface structured light three-dimensional measurement method, detecting depth information of each coordinate point from the image of the reflected light of the surface structured light to obtain first depth information; S15, combining the first depth information and the temperature information to construct a three-dimensional temperature field and obtain the phosphorescent surface temperature.

2. The curved surface temperature detection method based on digital light according to claim 1, characterized in that: The periodic signal of the surface structured light signal combined with the phosphorescence excitation signal is as follows: Each period of the periodic signal is formed by segmented combination of a phosphorescence excitation signal and a structured light signal; the phosphorescence excitation signal is a square wave light signal; and the surface structured light signal is a sinusoidal grating structured light.

3. The curved surface temperature detection method based on digital light according to claim 1, characterized in that: The temperature calibration is performed using a two-dimensional plane plate coated with a phosphorescent coating; the coating technology of the two-dimensional plane plate coated with the phosphorescent coating and the three-dimensional structure sample coated with the phosphorescent coating is the Weissenberg direct writing technology.

4. The curved surface temperature detection method based on digital light according to claim 1, characterized in that: In S13, the first camera is used to collect an image of phosphorescence return light, and the temperature information of each coordinate point in the image of phosphorescence return light is measured based on the fitting function of phosphorescence lifetime and temperature, as follows: The phosphorescence lifetime value corresponding to each coordinate is solved based on the three-frame method and the phosphorescence lifetime decay equation, and the phosphorescence lifetime value corresponding to each coordinate is substituted into the phosphorescence lifetime and temperature fitting curve function to obtain the temperature information corresponding to each coordinate.

5. The curved surface temperature detection method based on digital light according to claim 1, characterized in that: In S14, the image of the reflected light of the surface structured light is collected by the second camera, and the depth information of each coordinate point in the image of the reflected light of the surface structured light is measured based on the surface structured light three-dimensional measurement method, as follows: The second camera collects the reflected light of the surface structured light to obtain a reflected light image of the surface structured light corresponding to each phase difference value; The phase shift method is used to extract the phase, and the package phase and modulation value corresponding to each coordinate point are obtained; The phase values ​​of all coordinate points are unfolded by the phase fast unfolding method; The depth information of each coordinate point is obtained by reconstructing the Thornwell wavefront model.

6. The curved surface temperature detection method based on digital light according to claim 1, characterized in that: In S15, the three-dimensional temperature field is constructed by combining the first depth information and the temperature information, as follows: Match the first depth information with the corresponding plane coordinate points in the temperature information to obtain the depth information and temperature information under the same plane coordinates, display the coordinate information, depth information and temperature information in the same coordinate axis system, and finally obtain the three-dimensional temperature field based on the point cloud three-dimensional reconstruction technology.

7. A deformation detection method based on digital light, characterized in that: The digital light-based curved surface temperature detection method according to any one of claims 1 to 7 comprises: S21, without applying a simulated environment condition, a periodic signal combining a surface structured light signal and a phosphorescence excitation signal is projected by a projector onto a three-dimensional structured sample coated with a phosphorescent coating, thereby generating reflected light of the structured light under a non-simulated environment; S22, using a second camera to collect an image of the reflected light of the surface structured light, and measuring the depth information of each coordinate point in the image of the reflected light of the surface structured light based on a surface structured light three-dimensional measurement method to obtain second depth information; S23, reconstructing the first depth information and the second depth information in three dimensions in the same coordinate axis, and calculating a three-dimensional shape variable.

8. A curved surface temperature and deformation detection device based on digital light, comprising a projector, a dichroic mirror, a first lens, a first camera, a second camera, a second lens, a control system, a temperature controller and a heat stage; The projector receives the light code generated by the control system, generates and projects the corresponding projection light to the dichroic mirror; The dichroic mirror allows the projection light projected from the projector to be vertically projected through the top of the hot stage and projected onto the three-dimensional structure sample coated with the phosphorescent coating placed on the hot stage; the return light of the three-dimensional structure sample coated with the phosphorescent coating enters the second narrow light filter and enters the first narrow light filter through the dichroic mirror; The first narrow-band filter separates phosphorescence information in a specific wavelength range from the return light of the three-dimensional structure sample coated with the phosphorescent coating; the return light of the three-dimensional structure sample coated with the phosphorescent coating passes through the first narrow-band filter, the first lens and the first camera in sequence, and an image of the phosphorescent return light is generated and transmitted to the control system; the first camera is a high-speed camera; The second narrow-band filter separates structured light information in a specific wavelength range from the return light of the three-dimensional structure sample coated with the phosphorescent coating; the return light of the three-dimensional structure sample coated with the phosphorescent coating passes through the second narrow-band filter, the second lens and the second camera in sequence to generate an image of the reflected light of the surface structured light and transmit it to the control system; the second camera is a CCD camera or a CMOS camera; The hot stage is used to fix the three-dimensional structure sample or calibration plate coated with the phosphorescent coating; the temperature controller is used to control the change of the temperature of the hot stage; The control system generates light codes and controls the projection of the projector; A temperature controller connected to the heat stage is connected to control the temperature of the heat stage; image information from the first camera and the second camera is received and processed, and a three-dimensional temperature field is synthesized.

9. The curved surface temperature and deformation detection device based on digital light according to claim 8, characterized in that: The projector adopts DLP digital light processing technology for projection.

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