Spectral confocal sensor

Abstract

The embodiment of the invention discloses a spectral confocal sensor. The spectral confocal sensor comprises a spectrograph system, the spectrograph system comprises an optical subsystem, the optical subsystem comprises a spherical lens assembly and a cylindrical lens assembly, and the spherical lens assembly comprises a spherical lens and a cylindrical lens. The spherical lens assembly is used for receiving a first light beam propagating in the same direction, focusing the first light beam and outputting a second light beam; the second light beam can form a first light spot of which the root mean square (RMS) is in a regular circle in the photosensitive subsystem; the cylindrical lens assembly is arranged between the spherical lens assembly and the photosensitive subsystem and is used for receiving the second light beam, focusing the second light beam and outputting a third light beam; the light sensing subsystem is used for receiving the third light beam and generating a second light spot corresponding to the third light beam, and the RMS distribution of the second light spot is in a long strip shape.

Description

Technical Field

[0001] The present application relates to the technical field of spectral confocal distance measurement, and in particular to a spectral confocal sensor. Background Art

[0002] Spectral confocal sensor is an advanced optical sensing technology, which uses the optical confocal principle and spectral analysis technology to detect the distance of the sample. With the development needs, the resolution and measurement accuracy of the current spectral confocal sensor still need to be improved. Summary of the invention

[0003] In view of this, an embodiment of the present application provides a spectral confocal sensor. In the first aspect, an embodiment of the present application provides a spectral confocal sensor, comprising: a spectrometer system, the spectrometer system comprising: an optical subsystem, comprising: a spherical lens assembly and a cylindrical lens assembly, wherein; the spherical lens assembly is used to receive a first light beam propagating in the same direction, and focus the first light beam to output a second light beam; the second light beam can form a first light spot with a regular circular distribution of root mean square RMS in the photosensitive subsystem; the cylindrical lens assembly is arranged between the spherical lens assembly and the photosensitive subsystem, and is used to receive the second light beam, and focus the second light beam to output a third light beam; the photosensitive subsystem is used to receive the third light beam and generate a second light spot corresponding to the third light beam, wherein the RMS distribution of the second light spot is in the shape of a long strip.

[0004] In the above scheme, if the optical axis of the spherical mirror assembly is parallel to the horizontal direction; the angle between the cylindrical surface of the cylindrical lens assembly and the horizontal plane is a preset angle; wherein the range of the preset angle is [0°, 180°].

[0005] In the above scheme, the optical subsystem also includes: a collimating lens assembly and a grating assembly; wherein the collimating lens assembly is used to receive the first original light beam incident on the spectrometer system and collimate the first original light beam; the grating assembly is arranged between the collimating lens assembly and the spherical lens assembly, and is used to disperse the collimated first original light beam and output the first light beam to be transmitted in the same direction; the first light beam includes at least one monochromatic light beam.

[0006] In the above scheme, the optical subsystem further includes a first slit; the first slit is arranged before the collimating lens assembly; wherein the first slit is used to receive the first original light beam and filter the first original light beam to obtain the filtered first original light beam;

[0007] The collimating lens assembly is used to collimate the first original light beam after filtering.

[0008] In the above scheme, the grating component includes: a reflection grating or a transmission grating; wherein: the reflection grating is used to reflect the collimated first original light beam and output the first light beam; the transmission grating is used to transmit the collimated first original light beam and output the first light beam.

[0009] In the above scheme, the photosensitive subsystem includes: a photosensitive coupling component CCD.

[0010] In the above scheme, the spectral confocal sensor also includes: a light source system, which is used to generate a multi-color second original light beam; a dispersion system, which is arranged between the light source system and the object to be measured, and is used to receive the second original light beam, and focus the light of different wavelengths respectively after axial dispersion of the second original light beam, and transmit the first original light beam reflected by the object to be measured; the spectrometer system, which is used to receive the transmitted first original light beam, and focus the transmitted first original light beam onto the photosensitive subsystem included in the spectrometer system and quantify it into a spectral curve.

[0011] In the above scheme, the spectral confocal sensor also includes: a spectroscopic system, wherein; the spectroscopic system includes: a preprocessing component and a beam splitting component; the preprocessing component includes: a collimating lens, a cylindrical focusing lens, and a second slit; the beam splitting component includes: a semi-transparent and semi-reflective mirror arranged after the second slit; wherein the collimating lens is arranged on the side close to the light source system, and is used to receive the second original light beam, and collimate the second original light beam to obtain a fourth light beam propagating in the same direction; the cylindrical focusing lens is arranged after the collimating lens group, and is used to receive the fourth light beam, and focus the fourth light beam to obtain a fifth light beam; the second slit is arranged at the focus of the fifth light beam, and is used to receive the fifth light beam, and filter the fifth light beam to obtain a sixth light beam; the semi-transparent and semi-reflective mirror is used to transmit and reflect the sixth light beam.

[0012] In the above scheme, the spectroscopic system further includes: a light limiting component; the light limiting component includes: a rectangular light beam arranged between the collimating lens and the cylindrical focusing lens, for receiving the fourth light beam and adjusting the width of the fourth light beam.

[0013] In the above solution, the dispersion system is a dual telecentric system in the image and object spaces.

[0014] The embodiment of the present application provides a spectral confocal sensor. The spectral confocal sensor includes: a spectrometer system, the spectrometer system includes: an optical subsystem, including: a spherical lens assembly and a cylindrical lens assembly, wherein: the spherical lens assembly is used to receive a first light beam propagating in the same direction, and focus the first light beam to output a second light beam; the second light beam can form a first light spot with a regular circular distribution of root mean square RMS in the photosensitive subsystem; the cylindrical lens assembly is arranged between the spherical lens assembly and the photosensitive subsystem, and is used to receive the second light beam, and focus the second light beam to output a third light beam; the photosensitive subsystem is used to receive the third light beam and generate a second light spot corresponding to the third light beam, wherein the RMS distribution of the second light spot is in the shape of a long strip. The spectral confocal sensor provided in the embodiment of the present application forms a long strip of light spots in the photosensitive subsystem through the spherical lens assembly and the cylindrical lens assembly, thereby meeting the requirement of multiple pixels in a certain direction. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In the drawings, which are not necessarily drawn to scale, the same reference numerals may describe similar components in different views. The same numerals with different letter suffixes may represent different instances of similar components. The drawings generally illustrate various embodiments discussed in this document by way of example and not limitation.

[0016] Figure 1 A schematic diagram of the structure of a spectral confocal sensor provided in an embodiment of the present application;

[0017] Figure 2 A schematic diagram of the structure of a spectrometer system provided in an embodiment of the present application;

[0018] Figure 3 A schematic diagram of the RMS distribution of the first light spot provided in an embodiment of the present application;

[0019] Figure 4 A schematic diagram of the structure of a spherical lens assembly provided in an embodiment of the present application;

[0020] Figure 5 A schematic diagram of the structure of a one-dimensional cylindrical lens provided in an embodiment of the present application;

[0021] Figure 6 An exemplary structure diagram of an optical subsystem provided in an embodiment of the present application Figure 1 ;

[0022] Figure 7 Provide a method based on the embodiments of the present application Figure 6 Schematic diagram of the RMS distribution of the second light spot generated by the optical subsystem shown;

[0023] Figure 8An exemplary structure diagram of an optical subsystem provided in an embodiment of the present application Figure 2 ;

[0024] Fig. 9 Based on the embodiments of the present application Figure 8 Schematic diagram of the RMS distribution of the second light spot generated by the optical subsystem shown;

[0025] Fig.10 An exemplary schematic diagram of the distortion of a dispersion system when the double telecentric technology is not adopted provided in an embodiment of the present application;

[0026] Fig.11 An exemplary schematic diagram of the distortion of a dispersion system when a double telecentric technology is used according to an embodiment of the present application;

[0027] Among them, 100-spectral confocal sensor; 10-spectrometer system; 20-light source system; 30-spectrometric system; 40-dispersion system; 101-optical subsystem; 102-photosensitive subsystem; 1011-spherical lens assembly; 1012-cylindrical lens assembly; 1013-collimating lens assembly; 1014-grating assembly; 1015-first slit; 1021-photosensitive coupling assembly CCD; 301-collimating lens; 302-cylindrical focusing lens; 303-second slit; 401-dispersion focusing lens, which is a component in the dispersion system 40, which is set as a double telecentric system; among them, 301 to 303 constitute a pre-processing component; 304-rectangular glare, which is a light-limiting component; 305-semi-transparent and semi-reflective mirror, which is a beam splitting component. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the specific technical solution of the present application will be further described in detail below in conjunction with the drawings in the embodiments of the present application. The following embodiments are used to illustrate the present application, but are not used to limit the scope of the present application.

[0029] In the embodiments of the present application, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implying the number of technical features indicated by the term. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the feature. In the description of the embodiments of the present application, unless otherwise specified, "multiple" means two or more.

[0030] In addition, in the embodiments of the present application, directional terms such as "up", "down", "left" and "right" are defined relative to the orientation of the components in the drawings. It should be understood that these directional terms are relative concepts. They are used for relative description and clarification, and they may change accordingly according to changes in the orientation of the components in the drawings.

[0031] In the embodiments of the present application, the terms "include", "comprises" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes the elements in a step-by-step manner, and also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

[0032] In the embodiments of the present application, words such as "exemplarily" or "for example" are used to indicate examples, illustrations or explanations. Any embodiment or related scheme described as "exemplary" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary" or "for example" is intended to present related concepts in a specific way.

[0033] See also Figure 1 , which shows a schematic diagram of the structure of a spectral confocal sensor provided in an embodiment of the present application. Specifically, the spectral confocal sensor 100 may include: a spectrometer system 10, specifically, such as Figure 2 As shown, the spectrometer system 10 may include:

[0034] The optical subsystem 101 may include: a spherical lens assembly 1011 and a cylindrical lens assembly 1012, wherein: the spherical lens assembly 1011 is used to receive a parallel first light beam, and focus the first light beam to output a second light beam; the second light beam can form a first light spot with a regular circular root mean square RMS in the photosensitive subsystem 102; the cylindrical lens assembly 1012 is arranged between the spherical lens assembly 1011 and the photosensitive subsystem 102, and is used to receive the second light beam, and focus the second light beam to output a third light beam;

[0035] The photosensitive subsystem 102 is used to receive the third light beam and generate a second light spot corresponding to the third light beam, wherein the RMS distribution of the second light spot is in a strip shape.

[0036] It should be noted that the spherical lens assembly 1011 can be composed of a circularly symmetrical spherical lens, which can focus the incident first light beam to generate a second light beam. If the second light beam is received by the photosensitive subsystem 102, a symmetrical circular light spot will be generated in the photosensitive subsystem 102. In actual application, the intensity distribution of the light spot is reflected by the spatial distribution of the root mean square (RMS). That is to say, in optical imaging and beam quality analysis, the light spot can refer to a bright spot or spot formed on a certain plane after the light beam is focused; and the RMS distribution is used to describe the relative change in the light intensity in this light spot.

[0037] The above description is that, assuming that the first light beam is received by the photosensitive subsystem 102 after passing through the spherical lens assembly 1011, the light spot formed on the photosensitive subsystem 102 is a first light spot in a regular circular shape (that is, the symmetrical circle mentioned above), and its RMS distribution can be exemplarily shown as follows: Figure 3 As shown. In the embodiment of the present application, a cylindrical lens assembly 1012 is arranged between the spherical lens assembly 1011 and the photosensitive subsystem 102, so that the light spot formed by the third light beam obtained after processing by the cylindrical lens assembly 1012 on the photosensitive subsystem 102 is in the shape of a long strip. That is, the cylindrical lens assembly 1012 receives the second light beam and focuses the second light beam to form the third light beam. The third light beam is received by the photosensitive subsystem 102, and forms a second light spot in the shape of a long strip on the photosensitive subsystem 102. The RMS distribution of the second light spot is also in the shape of a long strip.

[0038] It should be noted that the structure of the spherical lens assembly can be as follows: Figure 4 The symmetric optical system shown in Figure 4 In the optical system shown in FIG. 1 , the light spot formed on the photosensitive subsystem 102 is a first light spot in a regular circular shape (i.e., the symmetrical circular shape mentioned above), and its RMS distribution can be exemplarily shown as follows: Figure 3 shown.

[0039] Here, the cylindrical lens assembly may include a set of two-dimensional plano-convex cylindrical lenses or two sets of one-dimensional plano-convex cylindrical lenses. The set of two-dimensional plano-convex cylindrical lenses or two sets of one-dimensional plano-convex cylindrical lenses can focus the second light beam into a third light beam with a light spot in the shape of an elongated strip.

[0040] In actual application, the position of the spherical lens assembly in the spectral confocal sensor is different, and the cylindrical lens group also changes with the change of the position of the spherical lens assembly.

[0041] An exemplary implementation may include: if the optical axis of the spherical lens assembly is parallel to the horizontal direction; the angle between the cylindrical surface of the cylindrical lens assembly and the horizontal plane is a preset angle; wherein the range of the preset angle is [0°, 180°].

[0042] For example, Figure 5 As shown, it shows a schematic diagram of the structure of a one-dimensional cylindrical lens assembly. Figure 5 In the figure, 1 is the plane of the cylindrical lens; 2 is the cylindrical surface of the cylindrical lens. When the incident light hits the cylindrical surface of the cylindrical lens assembly, it only has a focusing effect in one direction. For example, when the cylindrical surface of the cylindrical lens assembly is perpendicular to the horizontal plane, the cylindrical lens assembly is a straight line in the vertical direction without a curved surface, and has a curved surface in the horizontal direction and can refract. When a parallel light beam is incident on the cylindrical surface of the cylindrical lens assembly, the cylindrical lens assembly can focus the parallel light beam into a straight line; when a non-parallel light beam is incident, the imaging result will vary due to the different incident angles of the light. The method provided in the embodiment of the present application is to add cylindrical lens assemblies in different directions after a regular spherical lens assembly, so that the RMS of the light spot formed by the parallel light beam passing through the spherical lens assembly is shaped from the original regular distribution to a long strip shape, which can meet the algorithm requirements of higher measurement accuracy.

[0043] Here, the horizontal plane may be a relative concept. In different coordinate systems, the horizontal planes defined may be different.

[0044] For the placement between the spherical lens assembly and the cylindrical lens assembly, for example, Figure 6 and Figure 7 As shown, Figure 6 A schematic diagram showing a positional relationship between a cylindrical lens assembly and a spherical lens assembly; Figure 7 Show Figure 6 Schematic diagram of the result of the shape of the second light spot at the position. Figure 6 In the spherical lens assembly, the optical axis is parallel to the horizontal plane, where the horizontal plane refers to the plane perpendicular to the ground. At this time, the angle between the cylindrical surface of the cylindrical lens assembly and the horizontal plane is 0 degrees, or it is called a cylindrical lens group distributed in the horizontal direction. In other words, a cylindrical lens distributed in the horizontal direction is added after the spherical lens assembly, that is, the cylindrical lens assembly is added between the photosensitive subsystem and the spherical lens assembly, wherein the focal length of the cylindrical lens assembly can be determined according to the situation, for example, 38.7 mm. At this time, the second light spot with RMS stretched in the horizontal direction can be obtained in the photosensitive subsystem. Specifically, as Figure 7 As shown, the RMS ratio Figure 3 The regular light spot shown is stretched in the horizontal direction.

[0045] In other exemplary embodiments, Figure 8 and Fig. 9 As shown, Figure 8 Another schematic diagram showing the positional relationship between the cylindrical lens assembly and the spherical lens assembly; Fig. 9 Show Figure 8 Schematic diagram of the result of the shape of the second light spot at the position. Figure 8 In the spherical lens assembly, the optical axis is parallel to the horizontal plane, where the horizontal plane refers to the plane perpendicular to the ground. At this time, the angle between the cylindrical surface of the cylindrical lens assembly and the horizontal plane is 90 degrees, or it is called a cylindrical lens group distributed in the vertical direction. In other words, a cylindrical lens distributed in the vertical direction is added after the spherical lens assembly, that is, the cylindrical lens assembly is added between the photosensitive subsystem and the spherical lens assembly, wherein the focal length of the cylindrical lens assembly can be determined according to the situation, for example, 38.7 mm. At this time, the second light spot with RMS stretched in the horizontal direction can be obtained in the photosensitive subsystem. Specifically, as Fig. 9 As shown, the RMS ratio Figure 3 The regular light spot shown is stretched in the vertical direction.

[0046] In actual application, the above Figure 6 or Figure 8 The cylindrical lens assembly shown is rotated at corresponding angles to achieve stretching or scaling in different directions, wherein the angle between the cylindrical surface of the cylindrical lens assembly and the horizontal plane can be any angle between 0 degrees and 180 degrees.

[0047] In some embodiments, the optical subsystem 101 may further include: a collimating lens assembly 1013 and a grating assembly 1014; wherein the collimating lens assembly 1013 is used to receive the first original light beam incident on the spectrometer system and collimate the first original light beam;

[0048] The grating component 1014 is disposed between the collimating lens component 1013 and the spherical lens component 1011, and is used to perform dispersion processing on the collimated first original light beam and output the first light beam to be transmitted in the same direction; the first light beam includes at least one monochromatic light beam.

[0049] Here, the collimating lens assembly may include a collimating lens, which may be a special type of lens that can convert a divergent light beam into a parallel light beam, that is, collimate the first original light beam propagating in multiple directions and output a light beam propagating in the same direction (that is, parallel).

[0050] Here, the grating component can be an optical element with a periodic microstructure, which can be used to perform dispersion processing on the parallel first original light beam, and output parallel first light beams of different colors (or different wavelengths) to analyze the components of the monochromatic light beam contained in the first light beam. In actual application, the grating component 1014 may include a series of parallel, equidistant lines or grooves, and these lines may be transmissive or reflective, that is, in some embodiments, the grating component 1014 may include: a reflection grating or a transmission grating; wherein: the reflection grating is used to reflect the first original light beam and output the first light beam; the transmission grating is used to transmit the collimated first original light beam and output the first light beam.

[0051] If the spherical lens assembly 1011 and the cylindrical lens assembly 1012 are arranged behind the grating assembly 1014, the grating assembly 1014 can select the transmission grating. If the spherical lens assembly 1011 and the cylindrical lens assembly 1012 are arranged in front of the grating assembly 1014, and there is a certain angle between them (specifically, Figure 1 As shown), the grating component 1014 can select a reflective grating.

[0052] In some embodiments, the optical subsystem 101 further includes a first slit 1015; the first slit 1015 is disposed before the collimating lens assembly 1013; wherein,

[0053] The first slit 1015 is used to filter the first original light beam to obtain the filtered first original light beam;

[0054] The collimating lens assembly 1013 is used to collimate the first original light beam after filtering.

[0055] It should be noted that the first slit 1015 is applied to the spectrometer system to define the resolution of the spectrum, and the wavelength range to be analyzed is selected by adjusting the width of the slit, that is, in the present application, the first slit is used to filter the first original light beam to obtain the filtered first original light beam. Here, the collimating lens assembly 1013 is used to collimate the filtered first original light beam and output a parallel light beam.

[0056] In some embodiments, the photosensitive subsystem 102 may include: a photosensitive coupling component CCD1021.

[0057] It should be noted that the CCD is a semiconductor device that can convert optical images into digital signals. Among them, the tiny photosensitive substances implanted on the CCD are called pixels. The more pixels a CCD contains, the higher the image resolution it provides. In other words, the CCD acts like a film, but it converts image pixels into data signals and presents the shape of the second light spot with the data signal. In other words, the CCD does not change the shape of the second light spot that can be formed by the aforementioned third light beam, but only presents the shape of the second light spot that can be formed by the third light beam, that is, a long strip.

[0058] In some embodiments, the spectral confocal sensor 100 may further include:

[0059] A light source system 20, for generating a multi-color second original light beam;

[0060] a dispersion system 40, arranged between the light source system and the object to be measured, for receiving the second original light beam, focusing lights of different wavelengths respectively after axial dispersion of the second original light beam, and transmitting the first original light beam reflected by the object to be measured;

[0061] The spectrometer system 10 is used to receive the first original light beam transmitted, focus the first original light beam transmitted onto the photosensitive subsystem included in the spectrometer system, and quantify it into a spectrum curve.

[0062] Here, the light source system 20 can be used to generate a multi-color second original light beam, which can use a laser fluorescent system to generate a point light source; it can also use an LED lamp to emit light to illuminate fluorescent powder to generate white light; it can also use an LED lamp to directly generate white light, etc. In this application, the structure of the light source system is not limited.

[0063] Here, the dispersion system 40 is arranged between the light source system and the object to be measured, and is used to focus the light of different wavelengths respectively after axial dispersion of the second original light, and to conduct the reflected light emitted by the object to be measured. The reflected light can be the aforementioned first original light beam.

[0064] Here, the spectrometer system 10 is used to receive the first original light beam, focus the first original light beam onto the CCD, and quantify it into a spectrum curve. Here, the peak position of the spectrum curve corresponds to the wavelength of the light focused on the surface of the object to be measured; the spectrometer system establishes a corresponding relationship between the wavelength, the displacement of the object to be measured, and the peak position of the spectrum curve, and then analyzes it, and infers the displacement of the object to be measured through the peak of the spectrum curve, thereby realizing the process of measuring the displacement using the spectral confocal principle.

[0065] In some embodiments, the spectral confocal sensor may further include: a light splitting system 30, wherein the light splitting system 30 includes a pre-processing component and a beam splitting component; the pre-processing component includes: a collimating lens 301, a cylindrical focusing lens 302, and a second slit 303; the beam splitting component includes a semi-transparent and semi-reflective mirror 305 disposed after the second slit; wherein,

[0066] The collimating lens 301 is arranged near the light source system, and is used to receive the second original light beam and collimate the second original light beam to obtain a parallel fourth light beam;

[0067] The cylindrical focusing lens 302 is disposed after the collimating lens group, and is used to receive the fourth light beam and focus the fourth light beam to obtain a fifth light beam;

[0068] The second slit 303 is disposed at the focus of the cylindrical focusing lens group, and is used to receive the fifth light beam and filter the fifth light beam to obtain a sixth light beam;

[0069] The semi-transparent and semi-reflective mirror 305 is used to transmit and reflect the sixth light beam.

[0070] It should be noted that this is the structure of the spectroscopic system 30 before the dispersion system 40. Because the light source system 20 generates a multi-color and multi-directional light beam, it needs to be pre-processed by the spectroscopic system before entering the dispersion system for processing to form light beams in different directions for subsequent processing. Among them, the collimating lens 301, the cylindrical focusing lens 302, and the second slit 303 constitute a pre-processing component, which performs collimation, focusing, filtering and other processing on the second original light beam to form a sixth light beam that enters the semi-transparent and semi-reflective mirror. Here, the cylindrical focusing lens 302 can be a one-dimensional plano-convex cylindrical lens.

[0071] Here, the semi-transparent and semi-reflective mirror can be an optical mirror that is half transmissive and half reflective, which can achieve half transmission and half reflection of the received sixth light beam. When the transmitted light is reflected by the object to be measured to form emitted light and then irradiates the semi-transparent and semi-reflective mirror, the semi-transparent and semi-reflective mirror transmits half of the reflected light and reflects half of it, and sends the reflected emitted light into the spectrometer system 10.

[0072] In some embodiments, the optical splitting system 30 may further include: a light limiting component; the light limiting component includes: a rectangular light beam 304 disposed between the collimating lens and the cylindrical focusing lens, for receiving the fourth light beam and adjusting the width of the fourth light beam.

[0073] Here, the light-limiting component may be a rectangular light beam to adjust the width of the fourth light beam.

[0074] In some embodiments, the dispersive system is a doubly telecentric system.

[0075] The dispersion system may include a dispersion component; the dispersion component includes a dispersion focusing lens; the dispersion focusing lens is a double telecentric lens for the image side and the object side.

[0076] It should be noted that the dispersion system is set as a double telecentric system in which both the object and image sides are telecentric, so as to significantly improve the curvature of the field of view, so that the light entering the spectrometer system is corrected by the dispersion system to meet the requirements of X-direction resolution and reduce the distortion of the system. The so-called double telecentric system refers to a system in which both the object and image sides are telecentric, that is, the main light of the object and image sides is parallel to the optical axis, that is, the angle between the main light and the optical axis is 0 degrees. It is precisely because of this special situation that the double telecentric system has lower distortion than the conventional system.

[0077] For example, Fig.10 and Fig.11 ,in, Fig.10 is an exemplary schematic diagram of distortion of a dispersion system when the double telecentric technology is not adopted provided in an embodiment of the present application; Fig.11 An exemplary schematic diagram of the distortion of the dispersion system when the double telecentric technology is used in the embodiment of the present application. Wherein, when the double telecentric technology is not used, the distortion of the dispersion system is about 0.3%. After the double telecentric optimization, the distortion of the dispersion system is about 0.05%, that is, after the double telecentric technology is used, the distortion of the dispersion system is greatly reduced.

[0078] The spectral confocal sensor provided in the embodiment of the present application adjusts the distribution of the light spot into a long strip by combining a spherical lens assembly with a cylindrical lens assembly in the spectrometer system, thereby improving the multi-pixel requirement in the vertical (Z direction), and optimizing the dispersion system to be a double-telecentric system in both the object protection and image sides to reduce the distortion of the dispersion system, so that the light entering the spectrometer system meets the requirement of high resolution in the horizontal direction (X direction) after correction by the dispersion system. Utilizing the spectral confocal sensor of this design, a higher measurement accuracy of the sub-pixel precision positioning method based on high resolution in the x-direction and multi-pixels in the z-direction can be achieved. In general, the spectral confocal sensor provided in the embodiment of the present application can be added with a group of two-dimensional or two groups of one-dimensional cylindrical lenses to realize an optical system (such as Figure 3 The optical system shown in the figure) is used to shape the diffuse spot RMS, and a double telecentric system is built and optimized to reduce the distortion of the system. This greatly improves the measurement accuracy in the Z direction, solves the problem from a hardware perspective, and reduces the difficulty of the algorithm.

[0079] It should be noted that the terms “first”, “second”, etc. that appear in the present application are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence.

[0080] In addition, in the several embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. The device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as: multiple units or components can be combined, or can be integrated into another system, or some features can be ignored, or not executed. In addition, the coupling, direct coupling, or communication connection between the components shown or discussed can be through some interfaces, and the indirect coupling or communication connection of the devices or units can be electrical, mechanical or other forms.

[0081] The above description is only a preferred embodiment of the present application and is not intended to limit the protection scope of the present application.

Claims

1. A spectral confocal sensor, characterized in that: include: A spectrometer system, the spectrometer system comprising: The optical subsystem comprises: a spherical lens assembly and a cylindrical lens assembly, wherein: the spherical lens assembly is used to receive a first light beam propagating in the same direction, and focus the first light beam to output a second light beam; the second light beam can form a first light spot with a root mean square RMS in a regular circular distribution in the photosensitive subsystem; the cylindrical lens assembly is arranged between the spherical lens assembly and the photosensitive subsystem, and is used to receive the second light beam, and focus the second light beam to output a third light beam; The photosensitive subsystem is used to receive the third light beam and generate a second light spot corresponding to the third light beam, wherein the RMS distribution of the second light spot is in the shape of a long strip.

2. The spectral confocal sensor according to claim 1, characterized in that: If the optical axis of the spherical mirror assembly is parallel to the horizontal direction; the angle between the cylindrical surface of the cylindrical lens assembly and the horizontal plane is a preset angle; wherein the range of the preset angle is [0°, 180°].

3. The spectral confocal sensor according to claim 1, characterized in that: The optical subsystem further includes: a collimating lens assembly and a grating assembly; wherein, The collimating lens assembly is used to receive the first original light beam incident on the spectrometer system and collimate the first original light beam; The grating component is arranged between the collimating lens component and the spherical lens component, and is used to perform dispersion processing on the collimated first original light beam, and output the first light beam to be transmitted in the same direction; the first light beam includes at least one monochromatic light beam.

4. The spectral confocal sensor according to claim 3, characterized in that: The optical subsystem further comprises a first slit; the first slit is arranged before the collimating lens assembly; wherein, The first slit is used to receive the first original light beam and filter the first original light beam to obtain the filtered first original light beam; The collimating lens assembly is used to collimate the first original light beam after filtering.

5. The spectral confocal sensor according to claim 3, characterized in that: The grating component comprises: a reflection grating or a transmission grating; wherein: The reflection grating is used to reflect the collimated first original light beam and output the first light beam; The transmission grating is used to perform transmission processing on the collimated first original light beam and output the first light beam.

6. The spectral confocal sensor according to claim 1, characterized in that: The photosensitive subsystem includes: a photosensitive coupling component CCD.

7. The spectral confocal sensor according to claim 1, characterized in that: Also includes: A light source system for generating a polychromatic second original light beam; a dispersion system, arranged between the light source system and the object to be measured, for receiving the second original light beam, focusing lights of different wavelengths respectively after axial dispersion of the second original light beam, and conducting the first original light beam reflected by the object to be measured; The spectrometer system is used to receive the first original light beam transmitted, focus the first original light beam transmitted onto the photosensitive subsystem included in the spectrometer system, and quantify it into a spectrum curve.

8. The spectral confocal sensor according to claim 7, characterized in that: The spectral confocal sensor further comprises: a spectroscopic system, wherein: the spectroscopic system comprises: a preprocessing component and a beam splitting component; the preprocessing component comprises: a collimating lens, a cylindrical focusing lens, and a second slit; the beam splitting component comprises: a semi-transparent and semi-reflective mirror disposed after the second slit; wherein, The collimating lens is arranged near the light source system, and is used to receive the second original light beam and collimate the second original light beam to obtain a fourth light beam propagating in the same direction; The cylindrical focusing lens is arranged after the collimating lens group, and is used to receive the fourth light beam and perform focusing processing on the fourth light beam to obtain a fifth light beam; The second slit is arranged at the focus of the fifth light beam, and is used to receive the fifth light beam, filter the fifth light beam, and obtain the sixth light beam; the semi-transparent and semi-reflective mirror is used to transmit and reflect the sixth light beam.

9. The spectral confocal sensor according to claim 8, characterized in that: The light splitting system further includes: a light limiting component; the light limiting component includes: a rectangular light beam arranged between the collimating lens and the cylindrical focusing lens, for receiving the fourth light beam and adjusting the width of the fourth light beam.

10. The spectral confocal sensor according to claim 8, characterized in that: The dispersion system is a double telecentric system in the image and object spaces.

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