Orthogonal line spectrum confocal profile measurement sensor and anti-vibration method

Abstract

The present invention belongs to the technical field related to precision measurement, and discloses an orthogonal line spectrum confocal scanning profile measurement sensor and an anti-vibration method. The sensor includes a light source module, and first and second direction linear dispersion confocal imaging modules. The light source module is used to generate two beams of orthogonal collimated white light. The two beams of orthogonal collimated white light enter the first and second direction linear dispersion confocal imaging modules respectively, thereby scanning the surface of the sample to be measured and imaging, thereby obtaining the surface profile of the sample to be measured at two orthogonal angles. The first direction linear dispersion confocal imaging module includes a first linear dispersion confocal structure, a second slit, and a first imaging unit. The second direction linear dispersion confocal imaging module includes a second linear dispersion confocal structure, a third slit, and a second imaging unit. The directions of the second and third slits are respectively the same as the directions of the two orthogonal slits in the first slit. Through the present invention, the problem of vibration affecting measurement accuracy during line scanning surface measurement is solved.

Description

Technical Field

[0001] The present invention belongs to the technical field related to precision measurement, and more specifically, relates to an orthogonal line spectrum confocal scanning profile measurement sensor and an anti-vibration method. Background Art

[0002] Currently, precision surface measurement technology plays a vital role in a wide range of fields, including but not limited to the semiconductor, electronics, medical, and machinery industries. Optical line scanning measurement technology, with its non-contact, high-speed, and high-precision features, has become an indispensable tool in this field.

[0003] Existing line-scan confocal sensors are highly efficient surface line-scan measurement sensors. However, due to the complex and diverse surface structures, their adaptability to surface tilt angles needs to be improved. Furthermore, during line-scan surface measurement, including with existing line-scan confocal sensors, vibration can arise from a variety of factors, such as mechanical vibrations caused by the instrument itself or the external environment, as well as micro-vibrations of the sample itself due to motion errors or experimental conditions. These vibrations can reduce the stability and accuracy of line-scan measurements. Therefore, a vibration-resistant line-scan profilometry method is needed to mitigate the impact of vibration on imaging quality and improve measurement accuracy. Summary of the Invention

[0004] In response to the above defects or improvement needs of the prior art, the present invention provides an orthogonal line spectrum confocal profile measurement sensor and an anti-vibration method to solve the problem of vibration affecting measurement accuracy during line scanning surface measurement and the problem of surface structure angle adaptability.

[0005] To achieve the above object, according to one aspect of the present invention, an orthogonal line spectrum confocal profile measurement sensor is provided, which includes a light source module, a first direction line dispersion confocal imaging module and a second direction line dispersion confocal imaging module, wherein:

[0006] The light source module is used to generate two beams of orthogonal collimated white light; the two beams of orthogonal collimated white light enter the first direction linear dispersion confocal imaging module and the second direction linear dispersion confocal imaging module respectively to obtain the line profile of the surface of the sample to be measured in orthogonal directions;

[0007] The first-direction linear dispersion confocal imaging module includes a first linear dispersion confocal structure, a second slit, and a first imaging unit. The first linear dispersion confocal structure receives a beam of collimated linear white light from the light source module and disperses and focuses it on the surface of the sample to be measured as a second-direction measurement line. The second-direction measurement line is reflected by the surface of the sample to be measured and then returns to the first linear dispersion confocal structure to be collimated and focused. It then enters the first imaging unit through the second slit to form a second-direction line profile.

[0008] The second-direction linear dispersion confocal imaging module includes a second linear dispersion confocal structure, a third slit, and a second imaging unit. The second linear dispersion confocal structure receives another beam of collimated linear white light from the light source module and disperses and focuses it on the surface of the sample to be measured as a first direction measurement line orthogonal to the second direction measurement line. The first direction measurement line is reflected by the surface of the sample to be measured and then returns to the second linear dispersion confocal structure to be collimated and focused. It then enters the second imaging unit through the third slit to form a first direction line profile.

[0009] The directions of the second slit and the third slit are respectively the same as the directions of the two orthogonal slits in the first slit; the sensor and the sample to be tested move relative to each other to scan the surface of the sample to be tested, and the scanning direction is the same as the direction of the second slit / the third slit.

[0010] Further preferably, the optical axis of the first linear dispersion confocal structure is perpendicular to the surface of the sample to be measured, and it includes a third linear lens group, a second beam splitter prism and a fourth collimating lens group. The second beam splitter prism is used to receive a beam of collimated white light from the light source module and split it, wherein one beam of light is dispersed and focused onto the surface of the sample to be measured after passing through the third linear lens group, and then reflected by the surface of the sample to be measured and returned to the beam splitter prism along the original path. The third linear lens group is used to focus the light emitted from the second beam splitter prism on the surface of the sample to be measured in order of wavelength from high to low or from low to high, and the fourth collimating lens group is used to collimate the light from the second beam splitter prism and focus it into the second slit.

[0011] Further preferably, the second linear dispersion confocal structure includes a first linear dispersion unit, a second linear dispersion unit and a second collimating lens group. The first linear dispersion unit and the second linear dispersion unit are respectively distributed on both sides of the normal of the sample to be tested and are symmetrical about the normal of the sample to be tested. The two have the same structure. There is an angle between the optical axes of the first linear dispersion unit and the second linear dispersion unit and the normal direction of the sample to be tested. The first linear dispersion unit is used to disperse and focus another beam of collimated white light from the light source module on the surface of the sample to be tested. The second linear dispersion unit receives the light reflected from the surface of the sample to be tested and focuses the light on the third slit through the second collimating lens group.

[0012] Further preferably, the first linear dispersion unit includes a first reflection grating and a first linear lens group, the first reflection grating is used to disperse the collimated white light from the first beam splitter prism, and the first linear lens group is used to focus the light dispersed by the first reflection grating on the surface of the sample to be measured in order of wavelength from high to low or from low to high.

[0013] Further preferably, the light source module includes a white light source, a first slit, a first collimating lens group and a first beam splitter prism, the first slit is used to have two orthogonal slits arranged in the center, for converting the light of the white light source into mutually orthogonal linear white light, the first collimating lens group is used to collimate the orthogonal linear white light emitted from the first slit and enter the first beam splitter prism, the first beam splitter prism is used to split the orthogonal collimated linear white light from the first collimating lens group into two beams, one beam propagates to the first reflection grating, and the other beam propagates to the second beam splitter prism.

[0014] Further preferably, the first imaging unit includes a fifth collimating lens group, a plane reflector, a fourth reflective grating, a first imaging lens group, and a first camera; the fifth collimating lens group is used to collimate the light emitted from the second slit; the plane reflector is used to change the propagation direction of the light from the fifth collimating lens group; the fourth reflective grating is used to disperse and reflect the light from the plane reflector; the first imaging lens group is used to focus the light dispersed by the fourth reflective grating onto the first camera; and the first camera is used to image the light focused by the first imaging lens group;

[0015] The second imaging unit includes a third collimating lens group, a third reflection grating, a second imaging lens group and a second camera. The third collimating lens group is used to collimate the light emitted from the third slit, the third reflection grating is used to disperse and reflect the light from the third collimating lens group, the second imaging lens group is used to focus the light dispersed by the third reflection grating and image it onto the second camera, and the second camera is used to image the light focused by the second imaging lens group.

[0016] According to another aspect of the present invention, there is provided a vibration-proof method for performing line scanning surface vibration-proof measurement using the orthogonal line spectrum confocal profilometry sensor, the method comprising the following steps:

[0017] S1 uses the orthogonal line spectrum confocal profile measurement sensor to measure the sample to be measured, and synchronously obtains surface line profiles of the sample to be measured in two orthogonal directions under the influence of vibration, which are respectively a first direction line profile and a second direction line profile under the influence of vibration;

[0018] S2 calculates an average value of the profile data of the second direction line profile under the influence of vibration, and uses the average value as the profile data of the second direction line profile under the influence of vibration; using the intersection of the two orthogonal measurement lines to make a difference between the profile data of the first direction line profile under the influence of vibration and the profile data of the second direction line profile under the influence of vibration, and the difference is the relative vibration amount;

[0019] S3 uses the relative vibration amount obtained in step S2 to compensate the contour data of the first direction line profile under the influence of vibration, and obtains the contour data of the first direction line profile under the influence of vibration, that is, eliminates the vibration of the surface contour of the sample to be tested, and realizes the reconstruction of the surface of the sample to be tested.

[0020] Further preferably, in step S1, the contour data of the second direction line contour under the influence of vibration is x=[X1, X2, ..., X k ,…,X N ], the contour data of the first direction line contour under the influence of vibration is y=[Y1, Y2, ..., Y k ,…,Y M ], where x is the profile data of the second direction line profile under the influence of vibration, X1, X2, …, X k ,…,X N X is the profile data measured from the 1st point to the Nth point on the second direction measurement line affected by vibration. k is the contour data of the intersection point k of the second direction and the first direction measurement line on the second direction line contour, is the contour data of point n on the contour line measured by point N on the second direction measurement line under the influence of vibration, y is the contour data of the first direction line contour, Y1, Y2, ..., Y k ,…,Y M Y is the profile data measured from point 1 to point M on the first direction measurement line under the influence of vibration. k It is the contour data of the intersection point k between the second direction measurement line and the first direction measurement line on the contour of the first direction line.

[0021] Further preferably, in step S2, the relative vibration amount is calculated according to the following relationship:

[0022] ΔV i =Y k -x'

[0023] x'=[X1+X2+…+X k +…+X N ] / N

[0024] Where x' is the profile data of the second direction line profile without vibration, N is the number of points on the second direction measurement line, ΔV i is the i-th vibration quantity, Y k It is the contour data of the intersection point k between the second direction measurement line and the first direction measurement line on the contour of the first direction line under the influence of vibration.

[0025] Further preferably, in step S3, the contour data after the first direction line contour compensation is calculated according to the following relationship:

[0026] y'=y-ΔV i

[0027] Among them, y' is the contour data of the first direction line profile after compensation, y is the contour data of the first direction line profile under the influence of vibration, ΔV i is the i-th vibration quantity.

[0028] In general, the above technical solutions conceived by the present invention have the following beneficial effects compared with the prior art:

[0029] 1. The present invention proposes an orthogonal line spectrum confocal scanning profile measurement sensor. This sensor uses a light source module to generate orthogonal collimated white light. Based on the orthogonal collimated white light, a first linear dispersion confocal imaging structure, and a second linear dispersion confocal imaging structure, it can achieve synchronous measurement of the orthogonal line profile of the surface of a sample to be measured. The sensor and the sample to be measured move relative to each other to achieve synchronous scanning measurement of the orthogonal line profile of the sample to be measured.

[0030] 2. The orthogonal line spectral confocal scanning profile measurement sensor proposed in the present invention has good surface adaptability. The optical axis of the first linear dispersive confocal imaging module is perpendicular to the surface of the sample to be measured, and the surface inclination angle that can be measured is relatively small. At the same time, when measuring surfaces with varying brightness, matte surfaces, and rough surfaces, the signal noise increases, the contrast deteriorates, and the peak curve becomes broadened, resulting in poor measurement quality. The second linear dispersive confocal imaging module is provided with two linear dispersive units, and the optical axes of the two linear dispersive units form an angle with the surface normal of the sample to be measured. Therefore, it can achieve surface measurement with larger inclination angles, and maintain good signal quality for surfaces with varying brightness, matte surfaces, and rough surfaces, with higher measurement accuracy. However, if there is a step surface on the surface of the sample to be measured, the second linear dispersive confocal imaging module cannot measure the surface under the step, while the first linear dispersive confocal imaging module can measure it. Therefore, the orthogonal line spectral confocal scanning profile measurement sensor that integrates the first linear dispersive confocal imaging module and the second linear dispersive confocal imaging module has good adaptability to the inclination angle of the sample surface, and can meet the surface profile measurement requirements of samples with different inclination angles by adjusting the scanning direction.

[0031] 3. This invention proposes a vibration-resistant method for line-scan surface measurement. Under the influence of vibration, the surface is scanned and measured using two orthogonal measurement lines of an orthogonal line spectral confocal scanning profilometry sensor. One measurement line is in a first direction, and a sequence of surface line profiles in the first direction is acquired through scanning. The other measurement line is in a second orthogonal direction. During the scanning process, the orthogonal second-direction line profiles are simultaneously captured and analyzed to extract vibration information. This information is used to compensate for each horizontally captured line profile, and surface reconstruction is performed after removing the vibration effect, thereby achieving vibration-resistant measurement of line-scanned surfaces. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 1 is a schematic structural diagram of an orthogonal line spectrum confocal profile measurement sensor constructed according to a preferred embodiment of the present invention;

[0033] Figure 2 is a schematic diagram of surface measurement of a sample to be tested constructed according to a preferred embodiment of the present invention;

[0034] Figure 3 This is a flow chart of a vibration-resistant method for line scanning surface measurement using an orthogonal line spectrum confocal profilometry sensor constructed according to a preferred embodiment of the present invention;

[0035] Figure 4 It is a schematic diagram of the anti-vibration process of line scanning surface measurement constructed according to the preferred embodiment of the present invention.

[0036] Throughout the drawings, the same reference numerals are used to denote the same elements or structures, wherein:

[0037] 1-white light source, 2-first slit, 3-first collimating lens group, 4-first beam splitter, 5-first reflection grating, 6-first linear lens group, 7-sample to be measured, 8-third linear lens group, 9-second beam splitter, 10-fourth collimating lens group, 11-second slit, 12-fifth collimating lens group, 13-plane reflector, 14-fourth reflection grating, 15-first imaging lens group, 16-first camera, 17-second linear lens group, 18-second reflection grating, 19-second collimating lens group, 20-third slit, 21-third collimating lens group, 22-third reflection grating, 23-second imaging lens group, 24-second camera. DETAILED DESCRIPTION

[0038] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely for the purpose of explaining the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

[0039] like Figure 1 As shown, an orthogonal line spectrum confocal scanning profile measurement sensor includes a light source module, a first direction line dispersion confocal imaging module and a second direction line dispersion confocal imaging module, specifically including:

[0040] The light source module includes a white light source 1, a first slit 2, a first collimating lens group 3 and a first beam splitter prism 4. Two orthogonal slits are arranged at the center of the first slit 2, which are used to convert the LED white light source 1 into orthogonal line white light. The first collimating lens group 3 is used to collimate the orthogonal line white light emitted from the first slit 2 into orthogonal collimated linear white light. The orthogonal collimated linear white light enters the first beam splitter prism 4, and the reflected and transmitted light is split into two beams of orthogonal collimated linear white light, namely a first beam of collimated linear white light and a second beam of collimated linear white light. In an embodiment of the present invention, the white light source adopts an LED white light source.

[0041] The first-direction linear dispersion confocal imaging module includes a first linear dispersion confocal structure, a second slit 11 and a first imaging unit. The optical axis of the first linear dispersion confocal structure is perpendicular to the surface of the sample 7 to be measured. It includes a third linear lens group 8, a second beam splitter prism 9 and a fourth collimating lens group 10. The second beam splitter prism 9 is used to receive a first beam of collimated linear white light from the light source module, split the light and reflect it into the third linear lens group 8, disperse it by the third linear lens group 8 and focus it on the surface of the sample 7 to be measured as the second-direction measurement line. The corresponding wavelength light wave of the second-direction measurement line focused on the surface profile is reflected by the surface of the sample 7 to be measured and then returns to the third linear lens group 8. It is collimated by the third linear lens group 8, passes through the second beam splitter prism 9, and enters the fourth collimating lens group 10. It is focused on the second slit 11 by the fourth collimating lens group 10. The light passing through the second slit 11 has a spectral distribution in the slit length direction that corresponds to the surface profile height on the second-direction measurement line and enters the first imaging unit.

[0042] The first imaging unit includes a fifth collimating lens group 12, a plane mirror 13, a fourth reflection grating 14, a first imaging lens group 15, and a first camera 16. The fifth collimating lens group 12 collimates the light emitted from the second slit 11 and entering the first imaging unit. The light is reflected by the plane mirror 13 and enters the fourth reflection grating 14. The fourth reflection grating 14 reflects and diffracts light of different wavelengths corresponding to the profile height of each point on the second direction measurement line at different angles, and enters the first imaging lens group 15. The light is spectrally focused by the first imaging lens group 15 and imaged onto the first camera 16. The spectrally focused image obtained by the first camera 16 is then analyzed and calculated to obtain the measurement of the second direction line profile.

[0043] The second direction linear dispersion confocal imaging module includes a second linear dispersion confocal structure, a third slit 20 and a second imaging unit. The second linear dispersion confocal structure includes a first linear dispersion unit, a second linear dispersion unit and a second collimating lens group 19. The first linear dispersion unit and the second linear dispersion unit are symmetrically distributed on both sides of the normal line of the sample to be measured. The two have the same structure. The first linear dispersion unit includes a first reflection grating 5 and a first linear lens group 6. The second linear dispersion unit includes a second reflection grating 18 and a second linear lens group 17. The first reflection grating 5 disperses the second beam of collimated linear white light from the light source module, enters the first linear lens group 6, and is reflected by the first linear lens group 6 is focused on the surface of the sample 7 to be measured in the order of wavelength from high to low or from low to high, as the first direction measurement line orthogonal to the second direction measurement line. The light waves of the corresponding wavelengths focused on the surface of the sample 7 by the first direction measurement line are reflected by the surface of the sample to be measured and enter the second linear lens group 17. They are collimated by the second linear lens group 17 and further incident on the second reflection grating 18. They are converged and reflected by the second reflection grating 18 and enter the second collimating lens group 19. They are focused on the third slit 20 by the second collimating lens group 19. The spectrum distribution of the light passing through the third slit 20 in the length direction of the slit is highly consistent with the surface profile on the first direction measurement line, and enters the second imaging unit.

[0044] The second imaging unit includes a third collimating lens group 21, a third reflecting grating 22, a second imaging lens group 23, and a second camera 24. The third collimating lens group collimates the light emitted from the third slit and entering the second imaging unit, and the light enters the third reflecting grating 22. The third reflecting grating 22 reflects and diffracts the light of different wavelengths corresponding to the profile height of each point on the first direction measurement line from the third collimating lens group 21 at different angles, and the light enters the second imaging lens group 23. The second imaging lens group 23 spectrally focuses the light and forms an image on the second camera 24. After analyzing and solving the spectrally focused image obtained by the second camera 24, the measurement of the first direction line profile is obtained.

[0045] The directions of the second slit 11 and the third slit 20 are respectively the same as the directions of the two orthogonal slits in the first slit 2, are orthogonal to each other, and correspond to the directions of the second direction measurement line and the first direction measurement line, respectively; in this way, the orthogonal line spectral confocal profile measurement sensor, by the first direction line dispersion confocal imaging module and the second direction line dispersion confocal imaging module, synchronously obtains the second direction line profile and the first direction line profile where the second direction measurement line and the first direction measurement line are located, thereby realizing synchronous measurement of the orthogonal direction line profile of the surface to be measured, and drives the sensor and the sample to be measured to move relative to each other, thereby scanning the surface of the sample to be measured by the second direction measurement line and the first direction measurement line orthogonal thereto, thereby realizing synchronous scanning measurement of the orthogonal direction line profile of the surface of the sample to be measured.

[0046] In the present invention, the third collimating lens group 21 and the fifth collimating lens group 12 have the same structure, and the first imaging lens group 15 and the second imaging lens group 23 have the same structure. The collimating, focusing, and imaging functions achieved by the first collimating lens group 3, the second collimating lens group 19, the third collimating lens group 21, the fourth collimating lens group 10, the fifth collimating lens group 12, the first linear lens group 6, the second linear lens group 17, the third linear lens group 8, the first imaging lens group 15, and the second imaging lens group 23 are achieved using a conventional spherical lens combination structure. Corresponding structures are disclosed in the prior art, so the specific structures are not described in detail in this invention.

[0047] When performing scanning measurement, the first direction measurement line and the second direction measurement line of the sensor fall on the surface of the sample to be measured. The measurement line corresponding to the scanning direction is the longitudinal profile measurement line, and the measurement line perpendicular to the scanning direction is the transverse profile measurement line. Figure 2 As shown, the transverse profile measurement line and the longitudinal profile measurement line when scanning the sample to be measured are respectively shown.

[0048] In one embodiment of the present invention, under the influence of vibration, the workbench drives the sample to be measured to move to realize transverse profile measurement line scanning to obtain a series of transverse profiles, while continuously obtaining the longitudinal profile from the longitudinal profile measurement line. The true value of the longitudinal profile is obtained by analyzing the longitudinal profile data value. At the same time, the profile data measured at the intersection of the transverse and longitudinal measurement lines are analyzed to obtain vibration information, and the obtained transverse profile is compensated to obtain the actual profile. After further reconstruction, the surface line scanning surface vibration measurement is realized.

[0049] like Figure 3 As shown, based on the orthogonal line spectrum confocal scanning profile measurement sensor, the process of the line scanning surface measurement anti-vibration method for synchronously capturing orthogonal line profiles and performing vibration analysis and compensation proposed by the present invention is as follows:

[0050] S1. Using the orthogonal line spectrum confocal profile measurement sensor to measure the sample to be measured to obtain a series of transverse profiles, and simultaneously obtain a series of longitudinal profiles on orthogonal scanning direction lines;

[0051] During line scanning measurement, there are N points on the second direction measurement line. During line scanning measurement, each point on the measurement line measures all n points on the second direction line profile of the sample surface. The profile data of the second direction line profile is x = [X1, X2, ..., X k ,…,X N ],in

[0052] The first direction measurement line has M points in total, and the contour data is y=[Y1, Y2, ..., Y k ,…,Y M ], where x is the contour data of the second direction line contour, X1, X2, ..., X k ,…,X N X is the profile data measured from the 1st point to the Nth point on the second direction measurement line affected by vibration. k is the contour data value of the second direction line contour at the intersection point k of the first direction and the second direction measurement line, is the data value of point n on the contour line measured by point N on the second direction measurement line under the influence of vibration, y is the contour data of the first direction line contour, Y1, Y2, ..., Y k ,…,Y M Y is the profile data measured from the 1st point to the Mth point on the first direction measurement line under the influence of vibration, k The contour data value of the intersection point k of the first direction and the second direction measurement line in the first direction.

[0053] S2. Analyze the profile data of the second-direction line profile and calculate the average value of the data of the second-direction line profile as the true value excluding the vibration amount; use the intersection of the first-direction and second-direction measurement lines to obtain the true value of the profile data of the second-direction line profile and the profile data containing the vibration amount in the first direction, and use the difference between the two values ​​as the vibration amount;

[0054] The vibration amount is calculated according to the following relationship: x'=[X1+X2+…+X k +…+X N ] / N, ΔV i =Y k -x', where x' is the true value of the contour data of the second direction line contour, N is the number of measurement line points in the second direction, x is the contour data of the second direction line contour, X1, X2, ..., X k ,…,X Nis the profile data measured at each point on the second direction measurement line containing the vibration amount, ΔV i is the relative vibration amount, Y k The contour data value of the intersection of the first direction and the second direction measurement line on the first direction line contour.

[0055] S3. Compensating the first direction line profile data value using the acquired vibration amount, thereby eliminating the vibration influence on the surface profile of the sample to be measured and realizing reconstruction of the surface of the sample to be measured.

[0056] The contour data after the first direction line contour compensation is y'=y-ΔV i =[Y'1, Y'2, ..., Y' k ,…,Y' M ], where y' is the profile data after the first direction line profile compensation, y is the profile data of the first direction line profile, ΔV i is the relative vibration amount, Y'1, Y'2, ..., Y' k ,…,Y' M It is the contour data value measured from the 1st point to the Mth point on the measurement line in the first direction after compensation.

[0057] like Figure 4 As shown, the line scanning surface vibration resistance measurement method proposed in the present invention obtains longitudinal profile measurement by performing a first-direction contour line scanning measurement simultaneously with a second-direction measurement line. For the sample to be measured, the vibration direction is perpendicular to the surface of the sample to be measured, that is, the vibration direction is perpendicular to the first direction and the second direction. Therefore, the contour measurement data of the intersection of the first direction and the second direction can be used to analyze and obtain vibration information, and then the relative vibration amount obtained by the second direction measurement is used to compensate for the first-direction contour line scanning measurement, thereby realizing line scanning surface vibration resistance measurement.

[0058] The present invention not only possesses the aforementioned vibration-resistant properties but also exhibits excellent surface adaptability. By changing the scanning direction to accommodate different surface structures, the scanning direction of the first and second measurement lines can be switched, resolving the problem of triangular surface structures blocking light. Furthermore, when the surface to be measured has a large inclination angle, the two orthogonal measurement lines can be switched to a parallel state, enabling measurement of samples at large angles.

[0059] It will be easily understood by those skilled in the art that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. An orthogonal line spectrum confocal profile measurement sensor, characterized in that: The sensor includes a light source module, a first-direction line dispersion confocal imaging module and a second-direction line dispersion confocal imaging module, wherein: The light source module is used to generate two beams of orthogonal collimated white light; the two beams of orthogonal collimated white light enter the first direction linear dispersion confocal imaging module and the second direction linear dispersion confocal imaging module respectively to obtain the line profile of the surface of the sample (7) to be tested in the orthogonal direction; The first-direction linear dispersion confocal imaging module comprises a first linear dispersion confocal structure, a second slit (11), and a first imaging unit. The first linear dispersion confocal structure receives a beam of collimated linear white light from the light source module and disperses and focuses the beam on the surface of the sample to be measured (7) as a second-direction measurement line. The second-direction measurement line is reflected by the surface of the sample to be measured (7) and then returns to the first linear dispersion confocal structure to be collimated and focused. The second-direction measurement line then enters the first imaging unit through the second slit (11) to form a second-direction line profile. The second-direction linear dispersion confocal imaging module comprises a second linear dispersion confocal structure, a third slit (20) and a second imaging unit. The second linear dispersion confocal structure receives another beam of collimated linear white light from the light source module and disperses and focuses it on the surface of the sample to be measured (7) as a first direction measurement line orthogonal to the second direction measurement line. The first direction measurement line is reflected by the surface of the sample to be measured (7) and then returns to the second linear dispersion confocal structure to be collimated and focused. It enters the second imaging unit through the third slit (20) to form a first direction line profile. The directions of the second slit (11) and the third slit (20) are respectively the same as the directions of the two orthogonal slits in the first slit (2) provided in the light source module; the sensor and the sample to be tested (7) move relative to each other to scan the surface of the sample to be tested (7), and the scanning direction is the same as the direction of the second slit (11) and the third slit (20).

2. The orthogonal line spectrum confocal profile measurement sensor according to claim 1, characterized in that: The optical axis of the first linear dispersion confocal structure is perpendicular to the surface of the sample to be tested, and the structure comprises a third linear lens group (8), a second beam splitter prism (9) and a fourth collimating lens group (10). The second beam splitter prism (9) is used to receive a beam of collimated linear white light from the light source module and split it, wherein one beam of light is dispersed and focused onto the surface of the sample to be tested (7) after passing through the third linear lens group (8), and then reflected by the surface of the sample to be tested and returned to the beam splitter prism (9) along the original path. The third linear lens group (8) is used to focus the light emitted from the second beam splitter prism (9) onto the surface of the sample to be tested (7) in the order of wavelength from high to low or from low to high. The fourth collimating lens group (10) is used to collimate the light from the second beam splitter prism (9) and focus it into the second slit (11).

3. The orthogonal line spectrum confocal profile measurement sensor according to claim 1 or 2, characterized in that: The second linear dispersion confocal structure includes a first linear dispersion unit, a second linear dispersion unit and a second collimating lens group (19). The first linear dispersion unit and the second linear dispersion unit are respectively distributed on both sides of the normal line of the sample to be tested and are symmetrical about the normal line of the sample to be tested. The two have the same structure. There is an angle between the optical axes of the first linear dispersion unit and the second linear dispersion unit and the normal line direction of the sample to be tested. The first linear dispersion unit is used to disperse and focus another beam of collimated white light from the light source module on the surface of the sample to be tested (7). The second linear dispersion unit receives the light reflected from the surface of the sample to be tested (7) and focuses the light on the third slit (20) through the second collimating lens group (19).

4. The orthogonal line spectrum confocal profile measurement sensor according to claim 3, characterized in that: The first linear dispersion unit comprises a first reflection grating (5) and a first linear lens group (6), wherein the first reflection grating (5) is used to disperse the collimated white light from the first beam splitter prism (4), and the first linear lens group (6) is used to focus the light dispersed by the first reflection grating (5) on the surface of the sample to be measured (7) in the order of wavelength from high to low or from low to high.

5. The orthogonal line spectrum confocal profile measurement sensor according to claim 1 or 2, characterized in that: The light source module comprises a white light source (1), a first slit (2), a first collimating lens group (3) and a first beam splitting prism (4); two orthogonal slits are provided at the center of the first slit (2) for converting the light of the white light source (1) into mutually orthogonal linear white light; the first collimating lens group (3) is used to collimate the orthogonal linear white light emitted from the first slit (2) and enter the first beam splitting prism (4); the first beam splitting prism (4) is used to split the orthogonal collimated linear white light from the first collimating lens group (3) into two beams, one of which propagates toward the first reflection grating (5) and the other propagates toward the second beam splitting prism (9).

6. The orthogonal line spectrum confocal profile measurement sensor according to claim 1 or 2, characterized in that: The first imaging unit comprises a fifth collimating lens group (12), a plane reflector (13), a fourth reflective grating (14), a first imaging lens group (15) and a first camera (16), wherein the fifth collimating lens group (12) is used to collimate the light emitted from the second slit (11), the plane reflector (13) is used to change the propagation direction of the light from the fifth collimating lens group (12), the fourth reflective grating (14) is used to disperse and reflect the light from the plane reflector (13), the first imaging lens group (15) is used to focus the light dispersed by the fourth reflective grating (14) onto the first camera (16), and the first camera (16) is used to image the light focused by the first imaging lens group (15); The second imaging unit comprises a third collimating lens group (21), a third reflecting grating (22), a second imaging lens group (23) and a second camera (24), wherein the third collimating lens group (21) is used to collimate the light emitted from the third slit (20), the third reflecting grating (22) is used to disperse and reflect the light from the third collimating lens group (21), the second imaging lens group (23) is used to focus the light dispersed by the third reflecting grating (22) onto the second camera (24), and the second camera (24) is used to image the light focused by the second imaging lens group (23).

7. A vibration-proof method for performing line scanning surface vibration-proof measurement using the sensor according to any one of claims 1 to 6, characterized in that: The anti-vibration method includes the following steps: S1: using the sensor to measure the sample to be measured, and synchronously obtaining the surface line profiles of the sample to be measured in two orthogonal directions under the influence of vibration, namely, the first direction line profile and the second direction line profile; S2: taking the average value of the profile data of all points in the second direction line profile under the influence of vibration as the profile data of the second direction line profile under the influence of vibration; using the profile data of the first direction line profile under the influence of vibration at the intersection of the two orthogonal measurement lines to make a difference with the profile data of the second direction line profile under the influence of vibration, and the difference is the relative vibration amount; S3 uses the relative vibration amount to compensate for the contour data of the first direction line profile under the influence of vibration, obtains the contour data of the first direction line profile under the influence of vibration, eliminates the vibration of the surface contour image of the sample to be measured, and realizes reconstruction of the surface of the sample to be measured.

8. The anti-vibration method according to claim 7, wherein: In step S1, the contour data of the second direction line contour under the influence of vibration is x =[ X 1, X 2,…, X k ,…, X N ], the contour data of the first direction line contour under the influence of vibration is y =[ Y 1, Y 2,…, Y k ,…, Y M ],in, x is the contour data of the second direction line profile under the influence of vibration, , ,…, ,…, , X 1, X 2,…, X k ,…, X N It is the profile data measured from the 1st point to the Nth point on the second direction measurement line affected by vibration. X k The intersection of the second direction and the first direction measurement line k Contour data on the second direction line contour, hn N Points on the second direction measurement line under the influence of vibration N Measured points on the contour line n The contour data, y is the contour data of the first direction line contour, Y 1, Y 2,…, Y k ,…, Y M The first direction measurement line under the influence of vibration is from point 1 to point M The measured profile data, Y k The intersection of the second direction measurement line and the first direction measurement line k Contour data on the first direction line contour.

9. The anti-vibration method according to claim 7 or 8, characterized in that: In step S2, the relative vibration amount is calculated according to the following relationship: D V i = Y k - x' x' =[ X 1+ X 2+…+ X k +…+ X N ] / N in, x' is the contour data of the second direction line profile without vibration influence, N is the number of points on the second direction measurement line, Δ V i is the i-th vibration quantity, Y k The intersection of the second direction measurement line and the first direction measurement line k Contour data on a first direction line profile under the influence of vibration.

10. The anti-vibration method according to claim 7, wherein: In step S3, the contour data after the first direction line contour compensation is calculated according to the following relationship: y' = y -D V i in, y' is the contour data after the first direction line contour compensation, y is the profile data of the first direction line profile under the influence of vibration, Δ V i is the i-th vibration quantity.

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