A vertex measurement device and method based on spectral confocal technology

Abstract

The present invention discloses a vertex measurement device and method based on spectral confocal technology, comprising emitting multiple beams of light through multiple light exit apertures arranged in a preset geometric shape, dispersing the multiple beams of light into dispersed light beams of different wavelengths through a dispersion lens and irradiating the surface of a workpiece to be measured, then receiving reflected light, and transmitting the reflected light to a spectrum analysis device through a corresponding optical fiber channel; the spectrum analysis device analyzes the light intensity and wavelength of each group of reflected light to extract spectrum data; the height or spatial coordinates of the vertex on the workpiece surface are calculated according to the change of the spectrum data of each group of reflected light; the processing circuit outputs the calculated vertex height or spatial coordinate information; the method can effectively derive the vertex information of the workpiece through ingenious spectrum analysis and geometric fitting technology, and has wide applicability, especially suitable for high-precision vertex measurement scenarios of spherical, aspherical and conical surfaces.

Description

Technical Field

[0001] The present invention relates to the technical field, and in particular to a vertex measurement device and method based on spectral confocal technology. Background Art

[0002] With the rapid development of precision manufacturing and high-end optics, higher requirements are placed on the measurement accuracy of workpiece surface shape, especially vertex position. In the fields of aerospace, optical instruments, biomedicine, etc., accurate measurement of the vertex position and height of rotationally symmetrical workpieces such as spherical, aspherical and conical surfaces has a key impact on the performance and quality of the product. Traditional contact measurement methods are prone to damage the workpiece surface and are difficult to meet the requirements of high precision and high efficiency. Therefore, non-contact optical measurement technology has gradually become a hot spot for research and application.

[0003] At present, the commonly used spectral measurement technology mainly adopts the single-point measurement method, that is, emitting light through a single light exit hole, irradiating the surface of the workpiece after dispersion, and then receiving the reflected light for spectral analysis. This method has the problems of limited measurement range and low efficiency, and cannot fully obtain the morphological information of the workpiece surface. In addition, the existing technology often relies on machine learning models to infer the vertex position. The accuracy of the model is limited by the training data and algorithm, which may lead to inaccurate measurement results. Since only single-point measurement is performed, the random error in the measurement process cannot be effectively eliminated, the measurement accuracy is affected to a certain extent, and it is difficult to meet the needs of high-precision measurement.

[0004] In view of this, it is necessary to improve the spectral measurement technology in the prior art to solve the technical problem of large single-point measurement error. Summary of the invention

[0005] The purpose of the present invention is to provide a vertex measurement device and method based on spectral confocal technology to solve the above technical problems.

[0006] To achieve this object, the present invention adopts the following technical solutions:

[0007] A vertex measurement method based on spectral confocal technology, comprising:

[0008] Initialize the light source and calibrate the system, emit multiple beams of light through multiple light exit holes arranged in a preset geometric shape, disperse the multiple beams of light into dispersed light beams of different wavelengths through a dispersion lens, and irradiate different positions on the surface of the workpiece to be measured according to the preset geometric shape;

[0009] Reflected light is then received through the plurality of light exit apertures, and the reflected light is transmitted to a spectrum analysis device through corresponding optical fiber channels;

[0010] The spectrum analysis device analyzes the light intensity and wavelength of each group of reflected light to extract spectrum data;

[0011] The three-dimensional coordinates of each reflection point are determined by the change of the spectral data of each group of reflected light. The spatial coordinates of each reflection point are geometrically fitted with the known light exit hole position to calculate the height or spatial coordinates of the vertex on the workpiece surface.

[0012] The processing circuit outputs the calculated vertex height or spatial coordinate information.

[0013] Optionally, the initialization of the light source and calibration system, emitting multiple beams of light through multiple light exit holes arranged in a preset geometric shape, dispersing the multiple beams of light into dispersed light beams of different wavelengths through a dispersion lens, and irradiating different positions on the surface of the workpiece to be measured according to the preset geometric shape, specifically includes:

[0014] Start the light source and set the light intensity and spectrum range of the light source;

[0015] Adjust the relative position between the dispersion lens and the light exit aperture, and use a calibration workpiece or reference surface to calibrate the optical path of the dispersion lens;

[0016] A plurality of light exit apertures are arranged on the upper end surface of the dispersion adjustment lens according to a preset geometric shape.

[0017] Optionally, the method further comprises arranging the plurality of light exit apertures on the upper end surface of the dispersion adjustment lens in a preset geometric shape, and then:

[0018] Through a preset method or control system, each light exit aperture emits a light beam with preset parameters, and the emitted light beam is collimated and focused;

[0019] Each group of light beams passes through a dispersive lens and is dispersed into dispersed light beams of different wavelengths. The multiple groups of dispersed light beams are respectively irradiated to different positions on the surface of the workpiece to be measured through a layout of preset geometric shapes.

[0020] Optionally, the spectrum analysis device analyzes the light intensity and wavelength of each group of reflected light to extract spectrum data, specifically including:

[0021] The spectrum analysis device receives reflected light signals transmitted by a plurality of light exit apertures through corresponding optical fiber channels, and performs preliminary amplification and noise filtering on the received reflected light signals;

[0022] The reflected light signal after preliminary processing is introduced into the spectroscopic module of the spectrum analysis device, and the composite reflected light is separated into monochromatic lights of different wavelengths by using optical elements such as gratings, prisms or interference filters to form a continuous spectrum distribution area;

[0023] A photodetector array is used to detect optical signals of various wavelengths in the spectral distribution area, convert the optical signals into electrical signals, collect the electrical signal intensity corresponding to each wavelength, and generate digital spectral intensity data.

[0024] Optionally, the step of collecting the electrical signal intensity corresponding to each wavelength to generate digitalized spectrum intensity data further includes:

[0025] Analyze the wavelength shift and light intensity change of the spectral signal from the spectral intensity data to obtain spectral characteristic parameters related to the reflection point position, wherein the spectral characteristic parameters include peak wavelength, peak light intensity, and shape parameters of the spectral curve;

[0026] The extracted spectral characteristic parameters are sorted to generate a spectral data set corresponding to each reflection point, and the sorted spectral data is sent to the processing circuit.

[0027] Optionally, the three-dimensional coordinates of each reflection point are determined by the change of the spectral data of each group of reflected light, the spatial coordinates of each reflection point are geometrically fitted with the known light exit hole position, and the height or spatial coordinates of the vertex on the workpiece surface are calculated, which specifically includes:

[0028] For each group of reflected light, extract its spectral data through a spectral analysis device, obtain a characteristic curve of light intensity varying with wavelength, and identify the light intensity peak value corresponding to each wavelength based on the characteristic curve;

[0029] By comparing the wavelength shift in the incident spectrum and the reflected spectrum, the optical path change is determined, and the optical path difference at each reflection point is calculated based on the relationship between the wavelength and optical path of the dispersed light.

[0030] Based on the optical path difference and known system parameters, the optical path difference is converted into the distance information between each reflection point and the light exit hole;

[0031] The coordinates of each reflection point in three-dimensional space are calculated by using the distance information of each reflection point and the known position of the light exit hole and the triangulation method.

[0032] Optionally, the coordinates of each reflection point in three-dimensional space are calculated by using the distance information of each reflection point and the known position of the light exit hole using triangulation method, and then the method further includes:

[0033] Input the spatial coordinates of all reflection points into the geometric fitting algorithm, and perform surface model fitting in combination with some or all of the known shape parameters of the workpiece;

[0034] Based on the fitted surface model and surface differential analysis, the highest point on the surface is found to determine the vertex position of the workpiece surface.

[0035] The present invention also provides a vertex measurement device based on spectral confocal technology, which uses the vertex measurement method based on spectral confocal technology as described above to achieve measurement, and the vertex measurement device includes:

[0036] A light source module, used for providing an irradiation light source;

[0037] A plurality of light exit apertures are provided, wherein the plurality of light exit apertures are arranged into a preset geometric shape and connected to the light source module to emit detection light;

[0038] Dispersion lens, used to disperse multiple beams of light into dispersed beams of different wavelengths, and irradiate different positions on the surface of the workpiece to be measured according to preset geometric shapes;

[0039] Optical fiber, used to transmit reflected light;

[0040] A spectrum analysis device, used to analyze the light intensity and wavelength of each group of reflected light and extract spectrum data;

[0041] The processing circuit is used to calculate the height or spatial coordinates of the vertices on the workpiece surface through the changes in the spectral data of each group of reflected light and output the information.

[0042] Optionally, four light exit apertures are provided, three of which are arranged in a triangle, and the other light exit aperture is provided at the center of the triangle.

[0043] Compared with the prior art, the present invention has the following beneficial effects: first, the system initializes and calibrates the light source, and emits multiple beams of light through multiple light exit apertures arranged in a preset geometric shape. These light beams pass through a dispersion lens and are dispersed into light beams of different wavelengths, which are respectively irradiated to different positions on the surface of the workpiece to be measured; then, the light reflected from the workpiece surface is received through these light exit apertures, and the reflected light is transmitted to a spectrum analysis device through a corresponding optical fiber channel. The spectrum analysis device analyzes the light intensity and wavelength of each group of reflected light, extracts detailed spectral data, and determines the three-dimensional coordinates of each reflection point by analyzing the changes in the spectral data of each group of reflected light; then, the spatial coordinates of these reflection points are geometrically fitted in combination with the known positions of the light exit apertures, and the height or spatial coordinates of the vertices on the workpiece surface are calculated. The processing circuit outputs the calculated vertex height or spatial coordinate information to complete the vertex measurement process; the method can effectively derive the vertex information of the workpiece through ingenious spectral analysis and geometric fitting technology, and has wide applicability, especially for high-precision vertex measurement scenarios of spherical, aspherical and conical surfaces. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0045] The structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification so as to facilitate understanding and reading by persons familiar with this technology. They are not used to limit the conditions under which the present invention can be implemented, and therefore have no substantive technical significance. Any structural modification, change in proportion or adjustment of size, without affecting the effects and purposes that can be achieved by the present invention, should still fall within the scope of the technical contents disclosed by the present invention.

[0046] Figure 1 This is one of the flowcharts of the vertex measurement method of the first embodiment;

[0047] Figure 2 This is a second flow chart of the vertex measurement method of the first embodiment;

[0048] Figure 3 The third flowchart of the vertex measurement method of the first embodiment;

[0049] Figure 4 Schematic diagram of the system layout of the vertex measurement device of the second embodiment. DETAILED DESCRIPTION

[0050] In order to make the purpose, features and advantages of the present invention more obvious and easy to understand, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described below are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0051] In the description of the present invention, it should be understood that the terms "upper", "lower", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. It should be noted that when a component is considered to be "connected" to another component, it may be directly connected to the other component or there may be a centrally arranged component at the same time.

[0052] The technical solution of the present invention is further described below with reference to the accompanying drawings and through specific implementation methods.

[0053] Embodiment 1:

[0054] Combination Figures 1 to 3 As shown, an embodiment of the present invention provides a vertex measurement method based on spectral confocal technology, including:

[0055] S1, initialize the light source and calibrate the system, emit multiple beams of light through multiple light exit holes arranged in a preset geometric shape, disperse the multiple beams of light into dispersed light beams of different wavelengths through a dispersion lens, and irradiate different positions on the surface of the workpiece to be measured according to the preset geometric shape;

[0056] It includes setting the positions of the dispersion lens and multiple light exit holes; ensuring that the light emitted by the light source is accurately transmitted to the dispersion lens through the light exit holes, and the light is dispersed into different wavelengths by the dispersion lens, preparing to enter the measurement stage.

[0057] Multiple beams of light are emitted through multiple light exit holes arranged in different geometric shapes; these beams are dispersed into beams of different wavelengths through a dispersion lens, and irradiated to different positions on the surface of the workpiece to be measured according to a predetermined geometric layout. Each wavelength of light is dispersed and focused on a specific area on the surface of the workpiece to form a spectral coverage.

[0058] S2, receiving the reflected light through a plurality of light exit holes, and transmitting the reflected light through a corresponding optical fiber channel to a spectrum analysis device;

[0059] After the dispersed light beam is irradiated onto the workpiece surface, due to the protrusions (such as vertices) on the workpiece surface, the light generates reflected light when it contacts the workpiece surface;

[0060] S3, the spectrum analysis device analyzes the light intensity and wavelength of each group of reflected light to extract spectrum data; during the analysis process, the spectrum analysis device compares the reflection intensity of each wavelength with a preset spectrum database to determine the height change of each reflection point.

[0061] S4, determining the three-dimensional coordinates of each reflection point through the change of the spectrum data of each group of reflected light, geometrically fitting the spatial coordinates of each reflection point with the known light exit hole position, and calculating the height or spatial coordinates of the vertex on the workpiece surface;

[0062] S5, the processing circuit outputs the calculated vertex height or spatial coordinate information.

[0063] Set the coordinates of each light exit hole to (xi, yi, zi), and calculate the height Hv of each point through the wavelength change Δλi and the reflected light time difference Δti in the spectrum information;

[0064] Combined with the multi-point measurement method, the height data of multiple reflection points are used to deduce the precise position of the vertex based on the known formula of the rotationally symmetric geometric surface (spherical, aspherical or conical surface).

[0065] The working principle of the present invention is as follows: first, the system initializes and calibrates the light source, and emits multiple beams of light through multiple light exit apertures arranged in a preset geometric shape. These light beams pass through a dispersion lens and are dispersed into light beams of different wavelengths, which are respectively irradiated to different positions on the surface of the workpiece to be measured; then, the light reflected from the workpiece surface is received through these light exit apertures, and the reflected light is transmitted to a spectrum analysis device through a corresponding optical fiber channel. The spectrum analysis device analyzes the light intensity and wavelength of each group of reflected light, extracts detailed spectral data, and determines the three-dimensional coordinates of each reflection point by analyzing the time delay of each group of reflected light and the change of spectral data; then, the spatial coordinates of these reflection points are geometrically fitted in combination with the known positions of the light exit apertures, and the height or spatial coordinates of the vertex on the workpiece surface are calculated. The processing circuit outputs the calculated vertex height or spatial coordinate information to complete the vertex measurement process; the method can effectively derive the vertex information of the workpiece through ingenious spectral analysis and geometric fitting technology, and has wide applicability, especially for high-precision vertex measurement scenarios of spherical, aspherical and conical surfaces.

[0066] In this embodiment, it is specifically explained that step S1 specifically includes:

[0067] S11, start the light source, set the light intensity and spectral range of the light source; ensure the output consistency and reliability of the light source during the measurement process.

[0068] S12, adjust the relative position between the dispersion lens and the light exit hole, and use a calibration workpiece or a reference surface to calibrate the optical path of the dispersion lens; eliminate the measurement error caused by the deviation of the optical element, ensure that the light beam can accurately pass through the dispersion lens and achieve the expected dispersion effect.

[0069] S13, arranging a plurality of light exit apertures on the upper end surface of the dispersion adjustment lens according to a preset geometric shape. The position and spacing of each light exit aperture are designed according to the measurement requirements and the size of the workpiece to form a stable measurement reference, and the preset geometric shape is, for example, an equilateral triangle, a square, or other suitable polygons.

[0070] In this embodiment, it is further explained that after step S13, the following steps are further included:

[0071] S14, through a preset method or control system, each light exit hole emits a light beam with preset parameters, and the emitted light beam is collimated and focused; the preset parameters include light intensity, wavelength range and emission angle to ensure that the light beam quality meets the measurement requirements.

[0072] S15, each group of light beams passes through a dispersive lens and is dispersed into dispersed light beams of different wavelengths. The multiple groups of dispersed light beams are respectively irradiated to different positions on the surface of the workpiece to be measured through a layout of preset geometric shapes.

[0073] The design of the dispersion lens allows light beams of different wavelengths to propagate at different angles and focal lengths, providing an optical basis for multi-point measurement.

[0074] The dispersed light beam is controlled to irradiate different positions on the surface of the workpiece under test according to the preset geometric shape and optical path design; by adjusting the parameters of the light exit aperture and the dispersion lens, the irradiation point position of each light beam is precisely controlled to ensure that the key areas on the workpiece surface are covered, especially the positions close to the vertices.

[0075] The spatial coordinates of each light exit hole, the corresponding beam parameters (such as wavelength, light intensity) and the position of the irradiation point on the workpiece surface are recorded to provide the necessary initial conditions for subsequent data processing and vertex calculation.

[0076] In this embodiment, it is specifically described that step S3 specifically includes:

[0077] S31, the spectrum analysis device receives the reflected light signals transmitted by the multiple light exit holes through the corresponding optical fiber channels, and performs preliminary amplification and noise filtering on the received reflected light signals to ensure that the signal quality meets the analysis requirements.

[0078] S32, introducing the reflected light signal after preliminary processing into a spectroscopic module of a spectrum analysis device, and using optical elements such as gratings, prisms or interference filters to separate the composite reflected light into monochromatic lights of different wavelengths to form a continuous spectrum distribution area;

[0079] S33, using a photodetector array (such as CCD, CMOS or photomultiplier tube array) to detect the optical signals of each wavelength in the spectral distribution area, converting the optical signals into electrical signals, collecting the electrical signal intensity corresponding to each wavelength, and generating digital spectral intensity data.

[0080] Wavelength calibration: Use a calibrated light source with a known wavelength to calibrate the wavelength of the spectrum analyzer to establish the corresponding relationship between wavelength and pixel position; perform wavelength calibration on the collected spectral intensity data to ensure that the wavelength corresponding to each light intensity data is accurate.

[0081] Taking into account the response curve of the detector, the transmittance of the optical system and other factors, the light intensity data is corrected to eliminate the influence of system errors and environmental factors on the measurement results.

[0082] S34, analyzing the wavelength shift and light intensity change of the spectral signal from the spectral intensity data, and obtaining spectral characteristic parameters related to the reflection point position, the spectral characteristic parameters including peak wavelength, peak light intensity, shape parameters of the spectral curve (such as full width at half maximum FWHM, peak symmetry, etc.).

[0083] S35, sorting the extracted spectral characteristic parameters, generating a spectral data set corresponding to each reflection point, and sending the sorted spectral data to a processing circuit.

[0084] In this embodiment, it is specifically described that step S4 specifically includes:

[0085] S41, for each group of reflected light, extracting its spectrum data through a spectrum analysis device, obtaining a characteristic curve of light intensity varying with wavelength, and identifying the light intensity peak value corresponding to each wavelength based on the characteristic curve;

[0086] For each group of reflected light, a spectrum analysis device is used to extract detailed spectral data. Specifically, the spectrum analysis device measures the relationship between the intensity of the reflected light and the wavelength, and generates a complete characteristic curve. By analyzing this curve, the peak positions of the light intensity corresponding to each wavelength can be identified. These light intensity peaks reflect that the intensity of the reflected light reaches the maximum at a specific wavelength, which means that the light is significantly affected by the surface of the workpiece at these wavelengths, which facilitates the calculation of the optical path difference.

[0087] S42, determining the optical path change by comparing the wavelength shift in the incident spectrum and the reflected spectrum, and calculating the optical path difference of each reflection point by the relationship between the wavelength and the optical path of the dispersed light;

[0088] After completing the analysis of the reflected spectrum, it is compared with the incident spectrum, such as the wavelength shift. Since light will cause a specific wavelength shift when it is reflected on the surface of the workpiece, this shift is directly related to the change in optical path. By calculating the wavelength difference between the incident spectrum and the reflected spectrum, the change in optical path at each reflection point is determined. Using the known relationship between the wavelength of the dispersed light and the optical path, the optical path difference at each reflection point can be accurately calculated.

[0089] S43, based on the optical path difference and known system parameters, convert the optical path difference into the distance information between each reflection point and the light exit hole; this step uses the principle of geometric optics and combines the wavelength change of the dispersed light to accurately calculate the depth information of each reflection point.

[0090] Based on the optical path difference obtained in the previous step, and combined with the known parameters of the system (such as the refractive index of the medium, the initial position of the light source, etc.), the optical path difference is converted into the distance information between the reflection point and the light output aperture. This step needs to consider the propagation characteristics of light in different media and the geometric configuration of the optical system. Through precise mathematical models and formula calculations, the actual distance from each reflection point to the corresponding light output aperture is obtained, providing the necessary parameters for the calculation of spatial coordinates.

[0091] S44, using the distance information of each reflection point and the known position of the light exit aperture, using a triangulation method to calculate the coordinates of each reflection point in the three-dimensional space;

[0092] After obtaining the distance information of each reflection point and the position of the light-emitting aperture, the triangulation method is used to calculate the coordinates of each reflection point in three-dimensional space. Specifically, the spatial coordinate system is established using the known coordinates of the light-emitting aperture, the distance of the reflection point, and the incident and reflected angles of the light. By solving the relationship between the side length and angle of the triangle, the (x, y, z) coordinates of each reflection point are accurately determined. This step expands the one-dimensional distance information into three-dimensional spatial positioning and constructs a spatial distribution model of the reflection points.

[0093] S45, inputting the spatial coordinates of all reflection points into a geometric fitting algorithm, and performing surface model fitting in combination with some or all of the known shape parameters of the workpiece; and deriving the overall shape characteristics of the workpiece surface through the fitting results.

[0094] The three-dimensional spatial coordinates of all reflection points are collected and input into the geometric fitting algorithm. Combined with some or all of the known shape parameters of the workpiece (such as spherical radius, curvature change, etc.), the surface model of the workpiece surface is fitted. Through mathematical algorithms (such as least squares method, Bezier surface fitting, etc.), the overall shape characteristics of the workpiece surface can be reconstructed. The fitting result not only reflects the macroscopic contour of the workpiece surface, but also captures the tiny morphological changes, laying the foundation for the precise positioning of the vertex position.

[0095] S46, based on the fitted surface model, performing surface differential analysis, finding the highest point on the surface to determine the vertex position of the workpiece surface. The specific method may include performing surface differential analysis to find the highest point or other specific geometric feature points on the surface.

[0096] Based on the surface model of the workpiece obtained by fitting, the surface differential analysis is performed to find the highest point on the surface, that is, the vertex position of the workpiece. The extreme points on the surface are located by calculating the gradient and normal vector of the surface. This process requires the use of the principles of differential geometry to analyze the changing trend of the surface in different directions. After finding the highest point, the spatial coordinates and height information of the vertex can be determined to complete the accurate measurement of the vertex on the workpiece surface.

[0097] Embodiment 2:

[0098] Combination Figure 4 As shown, the present invention also provides a vertex measurement device based on spectral confocal technology, which uses the vertex measurement method based on spectral confocal technology as in Example 1 to achieve measurement, and the vertex measurement device includes:

[0099] The light source module is used to provide the illumination light source; the light source module provides uniform and stable light output, and after calibration, it emits multiple beams of light through the light exit hole. These beams need to have the characteristics of being decomposed into different wavelengths for dispersion processing.

[0100] There are multiple groups of light exit apertures 103, which are arranged in a preset geometric shape and connected to the light source module to emit detection light; multiple light exit apertures 103 are arranged in a preset geometric shape (such as an equilateral triangle or a square). These apertures can both emit light and receive light reflected from the workpiece to ensure the realization of multi-point measurement. The position of the light exit aperture 103 determines the measurement range and accuracy of the system.

[0101] The dispersion lens 104 is used to disperse multiple beams of light into dispersed beams of different wavelengths, and irradiate different positions on the surface of the workpiece to be measured according to the preset geometric shape; the dispersion lens 104 is located below the light exit hole 103, and decomposes the light into different wavelengths through refraction and dispersion effects, so that the beams of different wavelengths are irradiated to different surface areas of the workpiece. This module is one of the core components of the system for precise measurement, ensuring that the multi-wavelength light covers the surface of the workpiece.

[0102] The optical fiber 105 is used to transmit the reflected light; the optical fiber 105 connects the light exit hole 103 and the spectrum analysis device to efficiently transmit the reflected optical signal, avoid signal loss, and ensure the integrity and accuracy of the transmission.

[0103] The spectrum analysis device 102 is used to analyze the light intensity and wavelength of each group of reflected light and extract spectrum data; the spectrum analysis device 102 analyzes the spectrum signal returned by each optical fiber 105 channel. It extracts the wavelength, light intensity and its change of the reflected light, and converts this information into spectrum data for subsequent calculation of three-dimensional coordinates and vertex positions.

[0104] The processing circuit 101 is used to calculate the height or spatial coordinates of the vertices on the surface of the workpiece through the changes in the spectrum data of each group of reflected light and output the information.

[0105] According to the above structure, the vertex measurement device can realize accurate measurement of the workpiece surface through multiple light exit holes 103, dispersion lens 104 and spectrum analysis device 102. The light source emits light through the light exit hole 103, disperses it into light beams of different wavelengths through the dispersion lens 104 and irradiates the workpiece surface, and then receives the reflected light through the light exit hole 103, and finally transmits it to the spectrum analysis device 102 through the optical fiber for data analysis, and the processing circuit 101 completes the calculation of the vertex position. The various parts of the system work closely together to ensure high accuracy and reliability of the measurement.

[0106] It is further explained that there are 4 light exit apertures, 3 of which are arranged in a triangle, and the other light exit aperture is set at the center of the triangle. The measurement light of the 4 light exit apertures is irradiated onto the spherical surface or the conical surface to form measurement points. The type of the measured surface is preset in the data processing circuit. According to the positions of the 4 measurement points and the measured heights, the vertex of the spherical surface or the conical surface is fitted and calculated. The vertex can be the highest point or the most concave point of the spherical surface, or the highest point or the most concave point of the conical surface.

[0107] As described above, the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A vertex measurement method based on spectral confocal technology, characterized in that: include: Initialize the light source and calibrate the system, emit multiple beams of light through multiple light exit holes arranged in a preset geometric shape, disperse the multiple beams of light into dispersed light beams of different wavelengths through a dispersion lens, and irradiate different positions on the surface of the workpiece to be measured according to the preset geometric shape; Reflected light is then received through the plurality of light exit apertures, and the reflected light is transmitted to a spectrum analysis device through corresponding optical fiber channels; The spectrum analysis device analyzes the light intensity and wavelength of each group of reflected light to extract spectrum data; The three-dimensional coordinates of each reflection point are determined by the change of the spectral data of each group of reflected light. The spatial coordinates of each reflection point are combined with the known light exit hole position to perform geometric fitting on the workpiece with known partial or full shape parameters, and the height or spatial coordinates of the vertex on the workpiece surface are calculated; The processing circuit outputs the calculated vertex height or spatial coordinate information; The method of determining the three-dimensional coordinates of each reflection point by the change of the spectral data of each group of reflected light, geometrically fitting the spatial coordinates of each reflection point with the known light exit hole position, and calculating the height or spatial coordinates of the vertex on the workpiece surface specifically includes: For each group of reflected light, the spectrum data thereof is extracted by a spectrum analysis device to obtain a characteristic curve of light intensity varying with wavelength, and the light intensity peak value corresponding to each wavelength is identified based on the characteristic curve; specifically, the spectrum analysis device measures the relationship between the light intensity of the reflected light and the wavelength, and generates a complete characteristic curve, and the light intensity peak position corresponding to each wavelength is identified by analyzing the characteristic curve. The light intensity peak position reflects that the intensity of the reflected light reaches the maximum at a specific wavelength, which represents that the light is significantly affected by the surface of the workpiece at these wavelengths, and is used for calculating the optical path difference; By comparing the wavelength shift in the incident spectrum and the reflected spectrum, the optical path change is determined, and the optical path difference at each reflection point is calculated based on the relationship between the wavelength and optical path of the dispersed light. Based on the optical path difference and known system parameters, the optical path difference is converted into the distance information between each reflection point and the light exit hole; The coordinates of each reflection point in three-dimensional space are calculated by triangulation using the distance information of each reflection point and the known position of the light exit aperture. Specifically, a spatial coordinate system is established using the known light exit aperture coordinates, the distance of the reflection point, and the incident and reflected angles of the light. The (x, y, z) coordinates of each reflection point are accurately determined by solving the relationship between the side length and angle of the triangle. Input the spatial coordinates of all reflection points into the geometric fitting algorithm, and perform surface model fitting in combination with some or all of the known shape parameters of the workpiece; Based on the fitted surface model, surface differential analysis is performed to find the highest point on the surface to determine the vertex position on the workpiece surface; specifically: based on the fitted surface model of the workpiece surface, surface differential analysis is performed, by calculating the gradient and normal vector of the surface, and combining the principles of differential geometry, the changing trend of the surface in different directions is analyzed to locate the extreme point on the surface, that is, to find the highest point on the surface, and then determine the spatial coordinates and height information of the vertex to complete the measurement of the vertex on the workpiece surface.

2. The vertex measurement method based on spectral confocal technology according to claim 1 is characterized in that: The initialization light source and calibration system emits multiple beams of light through multiple light exit holes arranged in a preset geometric shape, disperses the multiple beams of light into dispersed light beams of different wavelengths through a dispersion lens, and irradiates different positions on the surface of the workpiece to be measured according to the preset geometric shape, specifically including: Start the light source and set the light intensity and spectrum range of the light source; Adjust the relative position between the dispersion lens and the light exit aperture, and use a calibration workpiece or reference surface to calibrate the optical path of the dispersion lens; A plurality of light exit apertures are arranged on the upper end surface of the dispersion adjustment lens according to a preset geometric shape.

3. The vertex measurement method based on spectral confocal technology according to claim 2 is characterized in that: The method further comprises: arranging the plurality of light exit apertures on the upper end surface of the dispersion adjustment lens in a preset geometric shape; and then: Through a preset method or control system, each light exit aperture emits a light beam with preset parameters, and the emitted light beam is collimated and focused; Each group of light beams passes through a dispersive lens and is dispersed into dispersed light beams of different wavelengths. The multiple groups of dispersed light beams are respectively irradiated to different positions on the surface of the workpiece to be measured through a layout of preset geometric shapes.

4. The vertex measurement method based on spectral confocal technology according to claim 1 is characterized in that: The spectrum analysis device analyzes the light intensity and wavelength of each group of reflected light to extract spectrum data, specifically including: The spectrum analysis device receives reflected light signals transmitted by a plurality of light exit apertures through corresponding optical fiber channels, and performs preliminary amplification and noise filtering on the received reflected light signals; The reflected light signal after preliminary processing is introduced into the spectroscopic module of the spectrum analysis device, and the composite reflected light is separated into monochromatic lights of different wavelengths by using optical elements such as gratings, prisms or interference filters to form a continuous spectrum distribution area; A photodetector array is used to detect optical signals of various wavelengths in the spectral distribution area, convert the optical signals into electrical signals, collect the electrical signal intensity corresponding to each wavelength, and generate digital spectral intensity data.

5. The vertex measurement method based on spectral confocal technology according to claim 4 is characterized in that: The step of collecting the electrical signal intensity corresponding to each wavelength to generate digitalized spectrum intensity data further includes: Analyze the wavelength shift and light intensity change of the spectral signal from the spectral intensity data to obtain spectral characteristic parameters related to the reflection point position, wherein the spectral characteristic parameters include peak wavelength, peak light intensity, and shape parameters of the spectral curve; The extracted spectral characteristic parameters are sorted to generate a spectral data set corresponding to each reflection point, and the sorted spectral data is sent to the processing circuit.

6. A vertex measurement device based on spectral confocal technology, characterized in that: The measurement is implemented by using the vertex measurement method based on spectral confocal technology as described in any one of claims 1 to 5, and the vertex measurement device comprises: A light source module, used for providing an irradiation light source; A plurality of light exit apertures are provided, wherein the plurality of light exit apertures are arranged into a preset geometric shape and connected to the light source module to emit detection light; Dispersion lens, used to disperse multiple beams of light into dispersed beams of different wavelengths, and irradiate different positions on the surface of the workpiece to be measured according to preset geometric shapes; Optical fiber, used to transmit reflected light; A spectrum analysis device, used to analyze the light intensity and wavelength of each group of reflected light and extract spectrum data; The processing circuit is used to calculate the height or spatial coordinates of the vertices on the workpiece surface through the changes in the spectral data of each group of reflected light and output the information.

7. The vertex measurement device based on spectral confocal technology according to claim 6 is characterized in that: There are four light exit apertures, three of which are arranged in a triangle, and the other light exit aperture is arranged at the center of the triangle.

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