Dispersion confocal measurement system and measurement method thereof

Abstract

The present invention provides a dispersive confocal measurement system and a measurement method thereof. The dispersive confocal measurement system performs position measurement through a first measurement unit and performs tilt angle measurement through a second measurement unit. While measuring the position information, the normal tilt angle at the measured point of the measured object is measured in real time. The dispersive confocal measurement method obtains the centroid position of the reflected light beam spot by the centroid method based on the light intensity distribution data of the corresponding confocal wavelength collected, and calculates the two-dimensional tilt angle through a mathematical model in combination with the position information determined first, thereby realizing real-time detection of the position and tilt angle, and has the advantages of low cost, high precision, wide measurement range, fast dynamic response speed, high signal-to-noise ratio, etc.

Description

Technical Field

[0001] The present invention relates to the field of optical detection technology, and in particular to a dispersion confocal measurement system and a measurement method thereof. Background Art

[0002] In recent years, with the deepening of research on nano-scale technologies such as ultra-precision machining and their wider application, ultra-precision detection, as a key link, is of great importance. Traditional contact measurement technology is easy to damage the measuring components and has poor real-time performance, so it is no longer used in the field of ultra-precision detection. Sub-micron or even nano-level measurement accuracy has brought new challenges to the research of non-contact measurement methods.

[0003] Among the ultra-precision non-contact measurement methods in the field of optics at this stage, common ones include laser triangulation, laser interferometry, grating interferometry, and dispersive confocal measurement. Laser triangulation has relatively high accuracy and integration capabilities, but it is limited to the measurement of highly reflective or inclined surfaces, and the defocused spot increases sharply near the focal position, which will lead to a decrease in lateral resolution. Laser interferometry performs linear incremental measurements on the reflective surface fixed on the moving target, and has high measurement performance, but it is also easily affected by environmental variables such as atmospheric pressure and temperature. In contrast, dispersive confocal measurement (CCT) uses dispersion phenomena and confocal technology to achieve focal length positioning by analyzing the reflection spectrum. It has the advantages of being insensitive to the tilt of the measured surface, high measurement accuracy, no need for additional accessories, and flexible integration. In addition, it can easily perform measurements by avoiding axial scanning operations, which is very difficult for laser scanning confocal or differential confocal microscopes.

[0004] However, when the existing technology of dispersive confocal measurement realizes the measurement of the three-dimensional coordinate information of the measured surface, it cannot realize the measurement of the tilt angle, that is, the normal vector information, at each measurement point. Therefore, dispersive confocal measurement has great research value and application prospects in morphology detection. Summary of the invention

[0005] The purpose of the present invention is to overcome the defects of the prior art and to provide a dispersion confocal measurement system and a measurement method thereof.

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

[0007] The dispersion confocal measurement system proposed in the present invention comprises a first measurement unit and a second measurement unit; wherein:

[0008] The first measuring unit comprises a light source assembly, a first beam splitter, a second beam splitter, a dispersive objective lens and a signal receiving assembly which are sequentially arranged along the optical path;

[0009] The light beam emitted by the light source assembly is incident on the surface of the object to be measured after being reflected by the first beam splitter, transmitted by the second beam splitter and transmitted by the dispersive objective lens. The light beam reflected back by the surface of the object to be measured is sequentially transmitted through the dispersive objective lens, the second beam splitter and the first beam splitter to the signal receiving assembly. The signal receiving assembly obtains the position information of the point to be measured on the surface of the object to be measured according to the received spectral signal.

[0010] The second measuring unit comprises a focusing lens, a third beam splitter, a first cylindrical mirror, a first linear array detector, a second cylindrical mirror and a second linear array detector which are sequentially arranged along the optical path;

[0011] The light beam reflected back from the surface of the object to be measured is sequentially transmitted through the dispersive objective lens, reflected by the second beam splitter to the focusing lens for collimation, and then incident on the third beam splitter for splitting. The transmitted light beam is sequentially incident on the first cylindrical mirror and the first linear array detector, and the reflected light beam is sequentially incident on the second cylindrical mirror and the second linear array detector. Data from the first linear array detector and the second linear array detector are collected, and the data is analyzed to obtain the inclination angle information of the point to be measured on the surface of the object to be measured.

[0012] Furthermore, the light source assembly includes a laser and a pinhole aperture;

[0013] The light beam emitted by the laser is emitted through the pinhole aperture to form a point light source.

[0014] Further, the signal receiving component includes a first confocal pinhole and a light receiving unit;

[0015] The light beam reflected by the object to be measured is incident on the first confocal pinhole filter and then incident on the light receiving unit, and the position information of the surface of the object to be measured is obtained by analyzing the data of the light receiving unit.

[0016] Further, the second measurement unit also includes a second confocal pinhole;

[0017] The light beam reflected back from the surface of the object to be measured is sequentially transmitted through the dispersion objective lens, reflected by the second beam splitter to the second confocal pinhole for filtering.

[0018] Furthermore, the pinhole aperture, the first confocal pinhole and the surface of the object to be measured are conjugate with each other.

[0019] Furthermore, the first confocal pinhole and the second confocal pinhole are distributed in a mirror image.

[0020] Furthermore, both the first cylindrical mirror and the second cylindrical mirror are plano-convex cylindrical lenses, and the convex surfaces of the two lenses are facing the third beam splitter.

[0021] The dispersion confocal measurement method proposed by the present invention comprises the following steps:

[0022] S1. Building a dispersive confocal measurement system, including the first measurement unit and the second measurement unit;

[0023] S2, measuring the to-be-measured point on the surface of the object to be measured, collecting the spectral signal received by the signal receiving component in the first measuring unit, and analyzing the spectral signal to obtain the corresponding position information of the to-be-measured point on the surface of the object to be measured;

[0024] Collecting data from the first linear array detector and the second linear array detector in the second measuring unit, calculating and correcting the specific position information of the center of mass by a center of mass method, and obtaining the inclination angle information of the point to be measured on the surface of the object to be measured according to the analysis of the specific position information of the center of mass;

[0025] S3. Combining the position information of the measured point and the inclination angle information on the surface of the object to be measured, simultaneously obtain the surface position information and the inclination angle information of the object to be measured.

[0026] Furthermore, the step S2 is specifically as follows:

[0027] S201, collecting the spectral signal received by the signal receiving component in the first measuring unit, obtaining the wavelength value at the maximum light flux by analyzing the spectral information of the specific wavelength light beam received by the signal receiving component, and extracting the peak wavelength, thereby obtaining the corresponding position information of any point on the surface of the object to be measured;

[0028] S202, collecting data of the first linear array detector and the second linear array detector, and calculating the centroid position information of the first linear array detector and the second linear array detector by using the centroid method using formula group (1) and formula group (2), where formula group (1) and formula group (2) are as follows:

[0029]

[0030] in, Respectively represent the pixel number coordinates corresponding to the first linear array detector and the second linear array detector; n represents the total number of pixels of the linear array detector; I ij represents the light intensity signal data on each pixel, i=x represents the signal data on the first linear array detector, i=y represents the signal data on the second linear array detector; j=1, 2, ..., n represents the specific pixel in the corresponding direction;

[0031]

[0032] in, Respectively represent the centroid position information corresponding to the first linear array detector and the second linear array detector; d represents the length and width of the pixel of the linear array detector;

[0033] S203, correct the center of mass position information according to formula group (3) to obtain corrected center of mass position information, where formula group (3) is as follows:

[0034]

[0035] Wherein, η represents the proportional coefficient, L represents the distance between the first confocal pinhole and the center point of the dispersion objective lens; f represents the focal length of the focusing lens; Respectively represent the corrected centroid position information;

[0036] S204, obtaining the inclination angle information of the point to be measured on the surface of the object to be measured according to formula group (4), where formula group (4) is as follows:

[0037]

[0038] Among them, f(λ i ) represents the wavelength λ corresponding to the point to be measured on the surface of the object to be measured i The focal length of the light beam; θ1 and θ2 respectively represent the inclination information of the normal vector at the test point on the surface of the object to be tested in two dimensions.

[0039] Furthermore, after step S201 and before step S202, a calibration step is also included:

[0040] After completing the position measurement of the test point on the surface of the object to be measured, place the plane mirror at the position of the object to be measured so that the normal vector at the test point on the surface of the object to be measured coincides with the optical axis of the dispersive objective lens, and obtain the position information of the center of mass at this time by the center of mass method to complete the calibration.

[0041] The present invention can achieve the following technical effects:

[0042] The present invention designs a dispersive confocal measurement system and a measurement method thereof on the basis of dispersive confocal displacement measurement, and utilizes the characteristic of a cylindrical mirror to shape a collimated light beam into a linear light source, thereby improving the signal-to-noise ratio. By collecting light intensity distribution data through a linear array detector, high precision can be achieved, and the dynamic response speed is faster and the real-time performance is better under high resolution. In addition, while detecting the position information, the inclination angle of the normal vector at the measured point in two dimensions can be measured in real time, realizing real-time dynamic detection of position and inclination angle, and having the advantages of low cost, high precision, wide measurement range, fast dynamic response speed, and high signal-to-noise ratio. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1is a schematic diagram of a dispersive confocal measurement system according to an embodiment of the present invention;

[0044] Figure 2 is a flow chart of a dispersion confocal measurement method according to an embodiment of the present invention;

[0045] Figure 3 Schematic diagram of the tilt principle of the measured surface in the dispersion confocal measurement method according to an embodiment of the present invention.

[0046] Reference numerals include:

[0047] Laser 1, pinhole aperture 2, first confocal pinhole 3, second confocal pinhole 4, first beam splitter 5, second beam splitter 6, third beam splitter 7, object to be measured 8, light receiving unit 9, dispersive objective lens 10, focusing lens 11, second cylindrical mirror 12, first cylindrical mirror 13, first linear array detector 14, second linear array detector 15. DETAILED DESCRIPTION

[0048] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the following description, the same modules are represented by the same reference numerals. In the case of the same reference numerals, their names and functions are also the same. Therefore, the detailed description thereof will not be repeated.

[0049] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and do not constitute a limitation of the present invention.

[0050] The specific working mode of the present invention is described in detail below with reference to the accompanying drawings:

[0051] The present invention provides a dispersion confocal measurement system, comprising a first measurement unit and a second measurement unit. The first measurement unit is used for position measurement, and the second measurement unit is used for two-dimensional inclination measurement. Figure 1 As shown, the first measuring unit includes a light source component, a first beam splitter 5, a second beam splitter 6, a dispersive objective lens 10 and a signal receiving component arranged in sequence along the optical path. In the embodiment of the present invention, the light source component in the dispersive confocal measurement system includes a laser 1 and a pinhole aperture 2. In the embodiment of the present invention, the signal receiving component in the dispersive confocal measurement system includes a first confocal pinhole 3 and a light receiving unit 9. In the embodiment of the present invention, the pinhole aperture 2, the first confocal pinhole 3 and the surface of the object to be measured 8 are conjugate with each other. The light receiving unit 9 in the embodiment of the present invention adopts a spectrometer in the prior art, and any device in the prior art that can collect spectral data can be used, and the present invention does not limit this.

[0052] The collimated white light beam emitted by the laser 1 is emitted through the pinhole diaphragm 2. After passing through the pinhole diaphragm 2, it can be approximated as a point light source. After the light beam is reflected by the non-polarized first beam splitter 5, transmitted by the non-polarized second beam splitter 6 and transmitted by the dispersive objective lens 10, based on the color coding principle, the focused light spots formed by the monochromatic lights of different wavelengths on the optical axis of the dispersive objective lens 10 are continuously and evenly distributed from short waves to long waves, and are incident on the surface of the object to be measured 8. These monochromatic lights with different focal positions are reflected by the surface of the object to be measured 8, and the reflected light beams are sequentially transmitted through the dispersive objective lens 10, the second beam splitter 6 and the first beam splitter 5 to the first confocal pinhole 3 and the light receiving unit 9. The first confocal pinhole 3 can achieve a filtering effect. When the light beam is reflected from the surface of the object to be measured 8 to the first confocal pinhole 3, only the light beams of the corresponding wavelengths that meet the confocal condition can pass through the first confocal pinhole 3, and other lights of the corresponding wavelengths in the defocused state will be blocked by the first confocal pinhole 3. Therefore, in the spectral data collected by the spectrometer, the single wavelength that meets the confocal condition has the highest light flux, and the other wavelengths are in a defocused state, so the light flux is relatively low, and the greater the defocus, the lower the light flux. Based on the above principle analysis, the peak wavelength λ extracted from the spectral data is i and the position of the measuring point f(λ i ), the height position information of the measuring point on the surface of the object to be measured 8 can be measured, that is, the position information of the measuring point on the surface of the object to be measured 8 can be obtained.

[0053] The second measurement unit in the embodiment of the present invention comprises a second confocal pinhole 4, a focusing lens 11, a third beam splitter 7, a first cylindrical mirror 13, a first linear array detector 14, a second cylindrical mirror 12, and a second linear array detector 15, which are sequentially arranged along the optical path. The first confocal pinhole 3 and the second confocal pinhole 4 in the embodiment of the present invention are distributed in a mirror image, so as to filter out the wavelength λ corresponding to the point to be measured on the surface of the object to be measured 8 to the greatest extent. iThe light beam of the corresponding wavelength in the out-of-focus state. The first cylindrical mirror 13 and the second cylindrical mirror 12 in the embodiment of the present invention are both plano-convex cylindrical lenses, and the convex surface faces the third beam splitter 7. In the embodiment of the present invention, the first cylindrical mirror 13 and the second cylindrical mirror 12 are used to realize the shaping of the circular light spot into a linear light source in the horizontal and vertical directions respectively, thereby improving the signal-to-noise ratio; and the first linear array detector 14 and the second linear array detector 15 collect the light intensity distribution signal data. The prior art often uses position sensors and area array detectors. The advantage of the position sensor is that it combines the principle of low rise time and integral measurement, but the measurement accuracy is greatly affected by the environment. At the same time, in order to avoid nonlinear errors, the measurement range is limited, and only the area within the central linear area can be selected. The reading time of the area array detector is too long, and it is difficult to meet the requirements of ultra-precision measurement real-time. In the embodiment of the present invention, the light source is shaped into a linear light source by a cylindrical mirror, and combined with a linear array detector, which can not only achieve high resolution to achieve high-frequency dynamic response, but also meet the high resolution. At the same time, the measurement range can also meet the performance indicators, and the real-time performance is better.

[0054] The light beam reflected back from the surface of the object to be measured 8 is sequentially transmitted through the dispersive objective lens 10, reflected by the second beam splitter 6 to the second confocal pinhole 4, and collimated by the focusing lens 11, and then incident on the third beam splitter 7 for splitting, and the transmitted light beam is sequentially incident on the first cylindrical mirror 13 and the first linear array detector 14, and the reflected light beam is sequentially incident on the second cylindrical mirror 12 and the second linear array detector 15, and the data of the first linear array detector 14 and the second linear array detector 15 are collected. When the surface of the object to be measured 8 is tilted, that is, when there is an angle between the normal vector at the surface of the object to be measured 8 and the optical axis of the dispersive objective lens 10, the center of mass of the reflected light beam will shift, and the center of mass shift angle is twice the normal tilt angle at the measuring point. Therefore, the collected data of the first linear array detector 14 and the second linear array detector 15 are analyzed by using the center of mass method, and then the tilt angle information of the surface of the object to be measured 8 is obtained.

[0055] The beneficial effects of the dispersive confocal measurement system of the present invention are as follows: the dispersive confocal measurement system provided by the embodiment of the present invention can filter out stray light and dark noise, and can measure the inclination angles of the normal vector at the test point on the surface of the object 8 in real time in two dimensions while detecting the position information. The characteristic of the cylindrical mirror to shape the collimated light beam into a linear light source is utilized to improve the signal-to-noise ratio. The light intensity distribution data is collected by the linear array detector, which can achieve high precision, faster dynamic response speed and better real-time performance under high resolution.

[0056] On the other hand, the embodiment of the present invention also provides a dispersion confocal measurement method, such as Figure 2 As shown, the following steps are included:

[0057] S1. Build a dispersion confocal measurement system, including a first measurement unit and a second measurement unit.

[0058] The first measuring unit for position measurement in the embodiment of the present invention comprises a laser 1, a pinhole aperture 2, a first beam splitter 5, a second beam splitter 6, a dispersive objective lens 10, a first confocal pinhole 3 and a light receiving unit 9, which are sequentially arranged along the optical path. The light receiving unit 9 in the embodiment of the present invention adopts a spectrometer in the prior art.

[0059] The second measuring unit for angle measurement in the embodiment of the present invention comprises a second confocal pinhole 4, a focusing lens 11, a third beam splitter 7, a first cylindrical mirror 13, a first linear array detector 14, a second cylindrical mirror 12 and a second linear array detector 15 which are sequentially arranged along the optical path.

[0060] S2, measuring the test point on the surface of the object 8 to be tested, collecting the spectral signal received by the signal receiving component in the first measuring unit, analyzing the spectral signal to obtain the corresponding position information of the test point on the surface of the object 8 to be tested. Collect the light intensity distribution data of the confocal wavelength of the first linear array detector 14 and the second linear array detector 15 in the second measuring unit, calculate and correct the specific position information of the center of mass by the centroid method, and then obtain the inclination angle information of the test point on the surface of the object 8 to be tested according to the analysis of the specific position information of the center of mass.

[0061] S201, collecting the spectral signal received by the signal receiving component in the first measurement unit, analyzing the spectral information of the specific wavelength light beam received by the signal receiving component, obtaining the wavelength value at the maximum light flux, and extracting the peak wavelength, and extracting the peak wavelength λ from the spectral information i and the position of the measuring point f(λ i ), the height position information of the measuring point on the surface of the object to be measured 8 can be measured, that is, the position information of the measuring point on the surface of the object to be measured 8 can be obtained.

[0062] In an embodiment of the present invention, a preferred method is provided. By completing calibration, the centroid extracted from the data collected by the linear array detector is linked to the relationship between the offset and the inclination angle in the theoretical mathematical model, thereby eliminating the offset error of the dispersive confocal measurement method, realizing the corresponding relationship between the linear array detector pixel and the inclination angle of the object to be measured 8, and further improving the accuracy of the inclination angle measurement. After completing the position measurement of the point to be measured on the surface of the object to be measured 8, the plane mirror is placed at the position of the object to be measured 8 so that the normal vector at the point to be measured on the surface of the object to be measured 8 coincides with the optical axis of the dispersive objective lens 10, that is, the plane mirror surface with an inclination angle of zero is used as a target for calibration. The data of the first linear array detector 14 and the second linear array detector 15 are collected, and the centroid position information of the first linear array detector 14 and the second linear array detector 15 when there is no inclination is calculated by the centroid method using formula group (1) and formula group (2), that is, the lateral and longitudinal position information of the centroid of the light beam are respectively The calibration is completed. The calculation formula group (1) and formula group (2) are as follows:

[0063]

[0064] in, They respectively represent the pixel number coordinates corresponding to the first linear array detector 14 and the second linear array detector 15 when there is no inclination; n represents the total number of pixels of the linear array detector; I ij represents the light intensity signal data on each pixel, i=x represents the signal data on the first linear array detector 14, i=y represents the signal data on the second linear array detector 15; j=1, 2, ..., n represents the specific pixel in the corresponding direction.

[0065]

[0066] in, They respectively represent the corresponding centroid position information of the first linear array detector 14 and the second linear array detector 15 when there is no inclination; d represents the length and width of the pixel of the linear array detector.

[0067] S202, collecting data from the first linear array detector 14 and the second linear array detector 15, and calculating the centroid position information of the first linear array detector 14 and the second linear array detector 15 by using the centroid method using formula group (3) and formula group (4). Formula group (3) and formula group (4) are as follows:

[0068]

[0069] in, I represents the pixel number coordinates corresponding to the first linear array detector 14 and the second linear array detector 15 respectively; n represents the total number of pixels of the linear array detector; ij represents the light intensity signal data on each pixel, i=x represents the signal data on the first linear array detector 14, i=y represents the signal data on the second linear array detector 15; j=1, 2, ..., n represents the specific pixel in the corresponding direction;

[0070]

[0071] in, They respectively represent the corresponding centroid position information of the first linear array detector 14 and the second linear array detector 15; d represents the length and width of the pixel of the linear array detector.

[0072] Since calibration is performed in the embodiment of the present invention, the centroid extracted from the data collected by the linear array detector is linked to the relationship between the offset and the tilt angle in the theoretical mathematical model, thereby eliminating the offset error of the dispersion confocal measurement method and further improving the accuracy of the tilt angle measurement. The centroid position information corresponding to the first linear array detector 14 and the second linear array detector 15 after calibration, that is, the longitudinal and lateral offsets of the centroid after calibration, are as shown in formula group (5):

[0073]

[0074] Wherein, △r1 and △r2 respectively represent the corresponding centroid position information of the first linear array detector 14 and the second linear array detector 15 after calibration.

[0075] S203, correct the centroid position information according to formula group (6) to obtain the corrected centroid position information, where formula group (6) is as follows:

[0076]

[0077] Wherein, η represents the proportional coefficient, L represents the distance between the first confocal pinhole 3 and the center point of the dispersive objective lens 10; f represents the focal length of the focusing lens 11; △r1' and △r2' respectively represent the corresponding centroid position information of the first linear array detector 14 and the second linear array detector 15 after correction, that is, the longitudinal and lateral offsets of the centroid of the light beam at the dispersive lens.

[0078] S204, such as Figure 3 As shown, when the surface of the object to be tested 8 is tilted, that is, when there is an angle between the normal vector at the surface of the object to be tested 8 and the optical axis of the dispersive objective lens 10, the center of mass of the reflected light beam will be offset. The center of mass offset angle is twice the normal tilt angle at the surface of the object to be tested 8. The specific offset can be approximately expressed as formula group (7). Therefore, according to formula group (7), the tilt angle information θ1 and θ2 of the surface of the object to be tested 8 is obtained. Formula group (7) is as follows:

[0079]

[0080] Among them, f(λ i ) represents the wavelength λ corresponding to the point to be measured on the surface of the object to be measured 8 i The focal length of the light beam is the position information of the test point on the surface of the object 8 to be tested; θ1 and θ2 respectively represent the inclination information of the normal vector at the test point on the surface of the object 8 to be tested and the optical axis of the dispersion lens in two dimensions.

[0081] S3. Combining the position information and the inclination angle information of the measured point on the surface of the measured object 8, simultaneously obtain the surface position information and the inclination angle information of the measured object 8.

[0082] The beneficial effects of the dispersion confocal measurement method of the present invention are as follows: the present invention designs a dispersion confocal measurement method based on the dispersion confocal displacement measurement. The system newly adds a first measurement unit for position measurement and a second measurement unit for tilt angle measurement. It can measure the normal tilt angle at the measured point in real time while measuring the displacement information. According to the collected light intensity distribution data of the corresponding confocal wavelength, the centroid position of the reflected light beam spot is obtained by the centroid method. Combined with the position information determined first, the two-dimensional tilt angle is calculated through a mathematical model, which realizes the real-time detection of the position and tilt angle and has the advantages of low cost, high precision, wide measurement range, fast dynamic response speed, and high signal-to-noise ratio.

[0083] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. 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 invention. In this specification, the schematic representations of the above terms do 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. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0084] Although the embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and cannot be understood as limiting the present invention. Those skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

[0085] The above specific implementations of the present invention do not constitute a limitation on the protection scope of the present invention. Any other corresponding changes and modifications made based on the technical concept of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A dispersive confocal measurement system, characterized in that: It includes a first measuring unit and a second measuring unit; wherein, The first measuring unit comprises a light source assembly, a first beam splitter, a second beam splitter, a dispersive objective lens and a signal receiving assembly which are sequentially arranged along the optical path; The light beam emitted by the light source component is incident on the surface of the object to be measured after being reflected by the first beam splitter, transmitted by the second beam splitter and transmitted by the dispersive objective lens. The light beam reflected back by the surface of the object to be measured is sequentially transmitted to the signal receiving component through the dispersive objective lens, the second beam splitter and the first beam splitter. The position information of the point to be measured on the surface of the object to be measured is obtained by analyzing the spectral signal received by the signal receiving component. The second measuring unit comprises a focusing lens, a third beam splitter, a first cylindrical mirror, a first linear array detector, a second cylindrical mirror and a second linear array detector which are sequentially arranged along the optical path; The light beam reflected back from the surface of the object to be measured is sequentially transmitted through the dispersive objective lens, reflected by the second beam splitter to the focusing lens for collimation, and then incident on the third beam splitter for splitting, the transmitted light beam is sequentially incident on the first cylindrical mirror and the first linear array detector, the reflected light beam is sequentially incident on the second cylindrical mirror and the second linear array detector, data from the first linear array detector and the second linear array detector are collected, and the inclination angle information of the surface of the object to be measured is obtained by analyzing the data; combined with the position information of the surface of the object to be measured obtained by the first measuring unit, the surface position information and inclination angle information of the object to be measured are simultaneously obtained; The signal receiving component includes a first confocal pinhole and a light receiving unit; The light beam reflected by the object to be measured is incident on the first confocal pinhole filter and then incident on the light receiving unit, and the position information of the surface of the object to be measured is obtained by analyzing the data of the light receiving unit; The second measurement unit further includes a second confocal pinhole; The light beam reflected back from the surface of the object to be measured is sequentially transmitted through the dispersive objective lens and reflected by the second beam splitter to the second confocal pinhole for filtering.

2. The dispersion confocal measurement system according to claim 1, characterized in that: The light source assembly includes a laser and a pinhole aperture; The light beam emitted by the laser is emitted through the pinhole aperture to form a point light source.

3. The dispersion confocal measurement system according to claim 2, characterized in that: The pinhole aperture, the first confocal pinhole and the surface of the object to be measured are conjugate to each other.

4. The dispersion confocal measurement system according to claim 3, characterized in that: The first confocal pinhole and the second confocal pinhole are distributed in a mirror image.

5. The dispersion confocal measurement system according to claim 1, characterized in that: The first cylindrical mirror and the second cylindrical mirror are both plano-convex cylindrical lenses, and the convex surfaces of the two lenses are facing the third beam splitter.

6. A measurement method using the dispersive confocal measurement system according to any one of claims 1 to 5, characterized in that: The steps include: S1. Building a dispersive confocal measurement system, including the first measurement unit and the second measurement unit; S2, measuring the to-be-measured point on the surface of the object to be measured, collecting the spectral signal received by the signal receiving component in the first measuring unit, and analyzing the spectral signal to obtain the corresponding position information of the to-be-measured point on the surface of the object to be measured; Collecting data from the first linear array detector and the second linear array detector in the second measuring unit, calculating and correcting the specific position information of the center of mass by a center of mass method, and obtaining the inclination angle information of the point to be measured on the surface of the object to be measured according to the analysis of the specific position information of the center of mass; S3. Combining the position information of the measured point and the inclination angle information on the surface of the object to be measured, simultaneously obtain the surface position information and the inclination angle information of the object to be measured.

7. The measuring method according to claim 6, characterized in that: The step S2 is specifically as follows: S201, collecting the spectral signal received by the signal receiving component in the first measuring unit, obtaining the wavelength value at the maximum light flux by analyzing the spectral information of the specific wavelength light beam received by the signal receiving component, and extracting the peak wavelength, thereby obtaining the corresponding position information of any point on the surface of the object to be measured; S202, collecting data of the first linear array detector and the second linear array detector, and calculating the centroid position information of the first linear array detector and the second linear array detector by using the centroid method, using formula group (1) and formula group (2), where formula group (1) and formula group (2) are as follows: in, Respectively represent the pixel number coordinates corresponding to the first linear array detector and the second linear array detector; n represents the total number of pixels of the linear array detector; I ij represents the light intensity signal data on each pixel, i=x represents the signal data on the first linear array detector, i=y represents the signal data on the second linear array detector; j=1, 2, ..., n represents the specific pixel in the corresponding direction; in, Respectively represent the centroid position information corresponding to the first linear array detector and the second linear array detector; d represents the length and width of the pixel of the linear array detector; S203, correct the center of mass position information according to formula group (3) to obtain corrected center of mass position information, where formula group (3) is as follows: Wherein, η represents the proportional coefficient, L represents the distance between the first confocal pinhole and the center point of the dispersion objective lens; f represents the focal length of the focusing lens; Respectively represent the centroid position information corresponding to the first linear array detector and the second linear array detector after correction; S204, obtaining the inclination angle information of the point to be measured on the surface of the object to be measured according to formula group (4), where formula group (4) is as follows: Among them, f(λ i ) represents the wavelength λ corresponding to the point to be measured on the surface of the object to be measured i The focal length of the light beam; θ1 and θ2 respectively represent the inclination information of the normal vector at the test point on the surface of the object to be tested and the optical axis of the dispersion lens in two dimensions.

8. The measuring method according to claim 7, characterized in that: After step S201 and before step S202, a calibration step is also included: After completing the position measurement of the test point on the surface of the object to be measured, place the plane mirror at the position of the object to be measured so that the normal vector at the test point on the surface of the object to be measured coincides with the optical axis of the dispersive objective lens, and obtain the position information of the center of mass at this time by the center of mass method to complete the calibration.

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