A spectral confocal sensor

Abstract

An embodiment of the present application discloses a spectral confocal sensor. Among them, the spectral confocal sensor includes: a spectrometer system, and 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 root mean square (RMS) in the photon sensing subsystem; the cylindrical lens assembly is arranged between the spherical lens assembly and the photon sensing subsystem, and is used to receive the second light beam and focus the second light beam to output a third light beam; a photon sensing subsystem, which 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 strip-shaped.

Description

Technical Field

[0001] This application relates to the technical field of spectral confocal ranging, and particularly to a spectral confocal sensor. Background Art

[0002] The spectral confocal sensor is an advanced optical sensing technology that uses the principle of optical confocal and spectral analysis technology to detect the distance of a sample. With the development requirements, the resolution and measurement accuracy of the current spectral confocal sensors still need to be improved. Summary of the Invention

[0003] In view of this, an embodiment of this application provides a spectral confocal sensor. In a first aspect, an embodiment of this application provides a spectral confocal sensor, including: a spectrometer system, where the spectrometer system includes: an optical subsystem, including: a spherical lens assembly and a cylindrical lens assembly, where; the spherical lens assembly is configured 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) distribution in a regular circular shape in the photon sensing subsystem; the cylindrical lens assembly is disposed between the spherical lens assembly and the photon sensing subsystem, and is configured to receive the second light beam, and focus the second light beam to output a third light beam; the photon sensing subsystem is configured to receive the third light beam and generate a second light spot corresponding to the third light beam, where the RMS distribution of the second light spot is in a strip shape.

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

[0005] In the above solution, the optical subsystem further includes: a collimating lens assembly and a grating assembly; where the collimating lens assembly is configured to receive a first original light beam incident on the spectrometer system, and collimate the first original light beam; the grating assembly is disposed between the collimating lens assembly and the spherical lens assembly, and is configured to disperse the collimated first original light beam to output the first light beam propagating in the same direction; the first light beam includes at least one monochromatic light beam.

[0006] In the above solution, the optical subsystem further includes a first slit; the first slit is disposed before the collimating lens assembly; where the first slit is configured 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 configured to collimate the filtered first original light beam.

[0008] In the above solution, the grating assembly 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 solution, the photosensitive sub-system includes: a Charge-Coupled Device (CCD).

[0010] In the above solution, the spectral confocal sensor further includes: a light source system for generating a multi-color second original light beam; a dispersion system disposed between the light source system and the object to be measured, for receiving the second original light beam, axially dispersing the second original light beam and focusing lights of different wavelengths respectively, and conducting the first original light beam reflected by the object to be measured; and a spectrometer system for receiving the conducted first original light beam, focusing the conducted first original light beam onto the photosensitive sub-system included in the spectrometer system, and quantifying it into a spectral curve.

[0011] In the above solution, the spectral confocal sensor further includes: a beam splitting system; wherein the beam splitting 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-transmissive and semi-reflective mirror disposed after the second slit; wherein, the collimating lens is disposed on the side close to the light source system, for receiving the second original light beam and collimating the second original light beam to obtain a fourth light beam propagating in the same direction; the cylindrical focusing lens is disposed after the collimating lens group, for receiving the fourth light beam and focusing the fourth light beam to obtain a fifth light beam; the second slit is disposed at the focal point of the fifth light beam, for receiving the fifth light beam, filtering the fifth light beam to obtain a sixth light beam; and the semi-transmissive and semi-reflective mirror is used for transmitting and reflecting the sixth light beam.

[0012] In the above solution, the beam splitting system further includes: a light limiting component; the light limiting component includes: a rectangular diaphragm 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.

[0013] In the above solution, the dispersion system is a double telecentric system for both the image side and the object side.

[0014] An embodiment of the present application provides a spectral confocal sensor. Among them, the spectral confocal sensor includes: a spectrometer system, and the spectrometer system includes: an optical subsystem, including: a spherical lens assembly and a cylindrical lens assembly, where; 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) distribution in the shape of a regular circle in the photon subsystem; the cylindrical lens assembly is disposed between the spherical lens assembly and the photon subsystem, and is used to receive the second light beam, and focus the second light beam to output a third light beam; the photon subsystem is used to receive the third light beam and generate a second light spot corresponding to the third light beam, where the RMS distribution of the second light spot is in the shape of a long strip. The spectral confocal sensor provided by the embodiment of the present application, through the spherical lens assembly and the cylindrical lens assembly, forms a long strip-shaped light spot in the photon subsystem, 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 the various embodiments discussed in this document by way of example and not limitation.

[0016] Figure 1 It is a schematic structural diagram of a spectral confocal sensor provided by an embodiment of the present application;

[0017] Figure 2 It is a schematic structural diagram of the spectrometer system provided by an embodiment of the present application;

[0018] Figure 3 It is a schematic diagram of the RMS distribution of the first light spot provided by an embodiment of the present application;

[0019] Figure 4 It is a schematic structural diagram of the spherical lens assembly provided by an embodiment of the present application;

[0020] Figure 5 It is a schematic structural diagram of a one-dimensional cylindrical lens provided by an embodiment of the present application;

[0021] Figure 6 It is an exemplary structural schematic of the optical subsystem provided by an embodiment of the present application Figure 1 ;

[0022] Figure 7 Based on the Figure 6 shown optical subsystem, it is a schematic diagram of the RMS distribution of the second light spot generated by an embodiment of the present application;

[0023] Figure 8An exemplary structural schematic of the optical subsystem provided by the embodiments of the present application Figure 2 ;

[0024] Figure 9 For the embodiments of the present application based on Figure 8 A schematic diagram of the RMS distribution of the second light spot generated by the optical subsystem shown;

[0025] Figure 10 An exemplary schematic diagram of the distortion of the dispersion system without using the double telecentric technology provided by the embodiments of the present application;

[0026] Figure 11 An exemplary schematic diagram of the distortion of the dispersion system when using the double telecentric technology provided by the embodiments of the present application;

[0027] Among them, 100 - spectral confocal sensor; 10 - spectrometer system; 20 - light source system; 30 - beam splitting 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 component CCD; 301 - collimating lens; 302 - cylindrical focusing lens; 303 - second slit; 401 - dispersion focusing lens, which is a component in the dispersion system 40 and is set as a double telecentric system; among them, 301 to 303 form a preprocessing component; 304 - rectangular diaphragm, which is a light limiting component; 305 - semi - transparent and semi - reflecting mirror, which is a beam splitting component. Detailed implementation manners

[0028] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the following will further describe the specific technical solutions of the present application in detail with reference to the accompanying 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 only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the embodiments of the present application, unless otherwise stated, the meaning of "a plurality" is two or more.

[0030] In addition, in the embodiments of the present application, orientation terms such as "upper", "lower", "left", and "right" are defined relative to the orientation of the components shown in the accompanying drawings. It should be understood that these directional terms are relative concepts, and they are used for relative description and clarification, and they can change accordingly with the change of the orientation of the components shown in the accompanying drawings.

[0031] In the embodiments of the present application, the term "comprise", "include" or any other variant thereof is intended to cover non-exclusive inclusion, such that a process, method, article or device that comprises a series of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article or device. Without further limitation, an element defined by the phrase "comprising a..." does not exclude the presence of additional identical elements in the process, method, article or device that comprises 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 solution described as "exemplary" or "for example" in the embodiments of the present application should not be construed as being more preferred or having more advantages than other embodiments or design solutions. Rather, the use of words such as "exemplary" or "for example" is intended to present relevant concepts in a specific manner.

[0033] See Figure 1 , which shows a schematic structural diagram of a spectral confocal sensor provided by the embodiments of the present application. Specifically, the spectral confocal sensor 100 may include: a spectrometer system 10. Specifically, as Figure 2 shown, the spectrometer system 10 may include:

[0034] An optical subsystem 101, which may include: a spherical lens assembly 1011 and a cylindrical lens assembly 1012. Among them, 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 photon subsystem 102; the cylindrical lens assembly 1012 is disposed between the spherical lens assembly 1011 and the photon subsystem 102 and is used to receive the second light beam and focus the second light beam to output a third light beam;

[0035] A photon subsystem 102, which 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. After 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 the 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 passes through the spherical lens assembly 1011 and is received by the photosensitive subsystem 102, the light spot formed on the photosensitive subsystem 102 is a first light spot in a regular circular shape (i.e., the symmetrical circle mentioned above), and its RMS distribution can be exemplarily shown as follows: Figure 3 As shown. In this embodiment of the present application, a cylindrical lens assembly 1012 is disposed between the spherical lens assembly 1011 and the photosensitive subsystem 102, so that the third light beam obtained after processing by the cylindrical lens assembly 1012 forms a long strip-shaped light spot on the photosensitive subsystem 102. 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 long strip-shaped second light spot on the photosensitive subsystem 102. The RMS distribution of the second light spot is also long strip-shaped.

[0038] It should be noted that the structure of the spherical lens assembly can be as follows: Figure 4 The symmetrical 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 the form of a regular circle (i.e., the symmetrical circle 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 the 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 cylinder of the cylindrical lens assembly and the horizontal plane is a preset angle; wherein, the range of the preset angle is [0°, 180°].

[0042] Exemplarily, as Figure 5 shown, which shows a schematic structural diagram of a one-dimensional cylindrical lens assembly. In Figure 5 , 1 is the plane of the cylindrical lens; 2 is the cylinder of the cylindrical lens. When the incident light irradiates the cylinder of the cylindrical lens assembly, it only has a focusing effect in one direction. For example, when the cylinder of the cylindrical lens assembly is perpendicular to the horizontal plane, the cylinder of this 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 light. When parallel light beams are incident on the cylinder of the cylindrical lens assembly, the cylindrical lens assembly can focus the parallel light beams into a straight line; when non-parallel light beams are incident, the imaging result will vary due to different incident angles of the light. The method provided in the embodiments of the present application is to add cylindrical lens assemblies in different directions after the regular spherical lens assembly, so that the RMS of the light spot formed by the parallel light beams passing through the spherical lens assembly is reshaped from the original regular distribution into a long strip shape, which can meet the algorithm requirements for higher measurement accuracy.

[0043] Here, the so-called horizontal plane can be a relative concept. In different coordinate systems, the defined horizontal plane can be different.

[0044] Regarding the placement between the spherical lens assembly and the cylindrical lens assembly, exemplarily, as Figure 6 and [[ID=!6]] Figure 7 shown, wherein, Figure 6 shows a schematic diagram of a positional relationship between the cylindrical lens assembly and the spherical lens assembly; Figure 7 shows Figure 6 the result schematic diagram of the shape of the second light spot at the Figure 6 position. In Figure 7 , the optical axis of the spherical lens assembly is parallel to the horizontal plane, and the horizontal plane here refers to the plane perpendicular to the ground. At this time, the angle between the cylinder of the cylindrical lens assembly and the horizontal plane is 0 degrees, or it is called a cylindrical lens group distributed along the horizontal direction. In other words, a cylindrical lens distributed along the horizontal direction is added after the spherical lens assembly, that is, the cylindrical lens assembly is added between the photosensing subsystem and the spherical lens assembly. The focal length of the cylindrical lens assembly can be determined according to the situation. For example, it is 38.7 mm. At this time, a second light spot with the RMS stretched along the horizontal direction can be obtained in the photosensing subsystem. Specifically, as Figure 3 shown, the RMS is stretched along the horizontal direction compared to the regular light spot shown in

[0045] In some other exemplary embodiments, such as Figure 8 and Figure 9 shown, Figure 8 shows another schematic diagram of the positional relationship between the cylindrical lens assembly and the spherical lens assembly; Figure 9 shows Figure 8 the result schematic diagram of the shape of the second light spot at the position. In Figure 8 , the optical axis of the spherical lens assembly 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 cylinder of the cylindrical lens assembly and the horizontal plane is 90 degrees, or it can be called a cylindrical lens group distributed along the vertical direction. In other words, a cylindrical lens distributed along the vertical direction is added after the spherical lens assembly, that is, the cylindrical lens assembly is added between the photosensing subsystem and the spherical lens assembly. Among them, the focal length of the cylindrical lens assembly can be determined according to the situation. For example, it is 38.7 mm. At this time, a second light spot with the RMS stretched along the horizontal direction can be obtained in the photosensing subsystem. Specifically, as Figure 9 shown, the RMS ratio Figure 3 the regular light spot shown is stretched along the vertical direction.

[0046] In the actual application process, the cylindrical lens assembly shown in the above Figure 6 or Figure 8 is rotated by a corresponding angle to achieve stretching or scaling in different directions. Among them, the angle between the cylinder 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 beam incident on the spectrometer system and collimate the first original beam;

[0048] The grating assembly 1014 is disposed between the collimating lens assembly 1013 and the spherical lens assembly 1011 and is used to disperse the collimated first original beam and output the first beam transmitted in the same direction; the first beam includes at least one monochromatic beam.

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

[0050] Here, the grating component mentioned can be an optical element with periodic microstructures, which can be used to disperse a 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 beams included in the first light beam. In the actual application process, the grating component 1014 can be composed of a series of parallel and equidistant lines or grooves, and these lines can be transmissive or reflective. That is, in some embodiments, the grating component 1014 can 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] Among them, if the spherical lens component 1011 and the cylindrical lens component 1012 are arranged behind the grating component 1014, then the grating component 1014 can select a transmission grating. If the spherical lens component 1011 and the cylindrical lens component 1012 are arranged in front of the grating component 1014 and there is a certain angle between their symmetries (specifically as Figure 1 shown), then the grating component 1014 can select a reflection grating.

[0052] In some embodiments, the optical subsystem 101 further includes a first slit 1015; the first slit 1015 is arranged before the collimating lens component 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 component 1013 is used to collimate the filtered first original light beam.

[0055] It should be noted that the first slit 1015 is applied to the spectrometer system to define the spectral resolution, and the wavelength range to be analyzed is selected by adjusting the width of the slit. That is, in this 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 component 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 can include: a charge-coupled device (CCD) 1021.

[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 (Pixels). The more pixels a CCD contains, the higher the resolution of the provided image. That is to say, the CCD functions like film, but it converts image pixels into data signals and presents the shape of the second light spot in the form of data signals. In other words, the CCD does not change the shape of the second light spot formed by the aforementioned third light beam, but only presents the shape of the second light spot formed by the third light beam, which is a long strip shape.

[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 disposed between the light source system and the object to be measured, for receiving the second original light beam, axially dispersing the second original light beam and then focusing lights of different wavelengths respectively, and conducting the first original light beam reflected by the object to be measured;

[0061] The spectrometer system 10 for receiving the conducted first original light beam, focusing the conducted first original light beam onto the photosensitive sub-system included in the spectrometer system and quantifying it into a spectral curve.

[0062] Here, the light source system 20 mentioned above can be used to generate a multi-color second original light beam. It can use a laser fluorescence system to generate a point light source; it can also use an LED lamp to emit light and irradiate a phosphor 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 disposed between the light source system and the object to be measured, for axially dispersing the second original light beam and then focusing lights of different wavelengths respectively, and conducting the reflected light emitted by the object to be measured. This 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 spectral curve. Here, the peak position of the spectral curve has a corresponding relationship with the wavelength of the light focused on the surface of the object to be measured; after establishing a corresponding relationship among the wavelength, the displacement of the object to be measured, and the peak position of the spectral curve, the spectrometer system analyzes and inversely calculates the displacement of the object to be measured through the peak of the spectral curve, realizing the process of measuring displacement using the spectral confocal principle.

[0065] In some embodiments, the spectral confocal sensor may further include: a beam splitting system 30. Among them, the beam splitting system 30 includes a preprocessing component and a beam splitting component; the preprocessing component includes: a collimating lens 301, a cylindrical focusing lens 302, and a second slit 303; the beam splitting component includes a semi-transmissive and semi-reflective mirror 305 disposed after the second slit; where,

[0066] The collimating lens 301 is disposed on the side close to the light source system, and is configured to receive the second original beam and collimate the second original beam to obtain a parallel fourth beam;

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

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

[0069] The semi-transmissive and semi-reflective mirror 305 is configured to perform transmission and reflection processing on the sixth beam.

[0070] It should be noted that here is the structure of the beam splitting system 30 before the dispersion system 40. Since the light source system 20 generates multi-color and multi-directional beams, before entering the dispersion system for processing, it needs to be preprocessed by the beam splitting system to form beams in different directions for subsequent processing. Among them, the collimating lens 301, the cylindrical focusing lens 302, and the second slit 303 form a preprocessing component, which collimates, focuses, filters, etc. the second original beam to form a sixth beam entering the semi-transmissive and semi-reflective mirror. Here, the so-called cylindrical focusing lens 302 may be a one-dimensional plano-convex cylindrical lens.

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

[0072] In some embodiments, the beam splitting system 30 may further include: a light limiting component; the light limiting component includes: a rectangular aperture 304 disposed between the collimating lens and the cylindrical focusing lens, and is configured to receive the fourth beam and adjust the width of the fourth beam.

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

[0074] In some embodiments, the dispersion system is a double telecentric system.

[0075] Among them, 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 here the dispersion system is set as a double telecentric system with both the object side and the image side being telecentric, so as to significantly improve the curvature of the field of view, make the light entering the spectrometer system meet the requirements of X-direction resolution after being corrected by the dispersion system, and reduce the distortion of the system. The so-called double telecentric system means that both the object side and the image side are telecentric systems, that is, the chief rays of the object side and the image side are parallel to the optical axis. That is to say, the angle between the chief ray and the optical axis is 0 degrees. Due to such a special situation, the double telecentric system has lower distortion than the conventional system.

[0077] Exemplarily, such as Figure 10 and Figure 11 , among which, Figure 10 is an exemplary schematic diagram of the distortion of the dispersion system when the double telecentric technology is not adopted in the embodiments of the present application; Figure 11 is an exemplary schematic diagram of the distortion of the dispersion system when the double telecentric technology is adopted in the embodiments of the present application. Among them, when the double telecentric technology is not adopted, the distortion of the dispersion system is about 0.3%. After being optimized by the double telecentric technology, the distortion of the dispersion system is about 0.05%. That is to say, after adopting the double telecentric technology, the distortion of the dispersion system is greatly reduced.

[0078] The spectral confocal sensor provided by the embodiments of the present application combines a spherical lens assembly and a cylindrical lens assembly in the spectrometer system to adjust the distribution of the light spot into a long strip shape, improve the requirements for multiple pixels in the vertical (Z-direction), and optimize the dispersion system into a double telecentric system with both the object side and the image side being telecentric to reduce the distortion of the dispersion system, so that the light entering the spectrometer system meets the requirements of high resolution in the horizontal direction (X-direction) after being corrected by the dispersion system. Using the designed spectral confocal sensor, a higher measurement accuracy can be achieved for the sub-pixel precision positioning method based on high resolution in the x-direction and multiple pixels in the z-direction. Generally speaking, the spectral confocal sensor provided by the embodiments of the present application can add a group of two-dimensional or two groups of one-dimensional cylindrical lenses to realize the shaping of the RMS of the diffuse spot of the optical system (such as Figure 3 the shown optical system), and additionally build a double telecentric system for optimization to reduce the distortion of the system. Thus, the measurement accuracy in the Z direction can be greatly improved, problems can be solved from a hardware perspective, and the difficulty of the algorithm can be reduced.

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

[0080] In addition, in 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 merely illustrative. For example, the division of the units is only a logical function division. In actual implementation, there may be other division methods. For example, 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 with each other can be through some interfaces. The indirect coupling or communication connection of devices or units can be electrical, mechanical, or other forms.

[0081] The above 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, 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 root mean square (RMS) distribution in the photon sensor subsystem; the cylindrical lens assembly is arranged between the spherical lens assembly and the photon sensor subsystem, and is used to receive the second light beam and focus the second light beam to output a third light beam; The photon sensor 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 a strip shape.

2. The spectral confocal sensor according to claim 1, wherein If the optical axis of the spherical lens assembly is parallel to the horizontal direction; the angle between the cylinder 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 comprises: a collimating lens assembly and a grating assembly; wherein, The collimating lens assembly is used to receive a 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 to output the first light beam propagating 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 filtered first original light beam.

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

6. The spectral confocal sensor according to claim 1, wherein The photon sensor subsystem comprises: a charge-coupled device (CCD).

7. The spectral confocal sensor according to claim 1, wherein Further comprising: A light source system, used to generate a multi-color second original light beam; A dispersion system, arranged between the light source system and the object to be measured, used to receive the second original light beam, axially disperse the second original light beam, focus lights with different wavelengths respectively, and conduct the first original light beam reflected by the object to be measured; The spectrometer system is used to receive the conducted first original light beam, focus the conducted first original light beam on the photon sensor subsystem comprised in the spectrometer system and quantify it into a spectral curve.

8. The spectral confocal sensor according to claim 7, wherein The spectral confocal sensor further comprises: a beam splitting system, wherein; the beam splitting system comprises: a preprocessing component and a beam splitting component; the preprocessing component comprises: a collimating lens, a cylindrical focusing lens, a second slit; the beam splitting component comprises: a semi-transmissive and semi-reflective mirror arranged after the second slit; wherein, The collimating lens is arranged near the light source system side, 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 behind the collimating lens, 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, filter the fifth light beam to obtain a sixth light beam; the semi-transmissive and semi-reflective mirror is used to perform transmission and reflection processing on the sixth light beam.

9. The spectral confocal sensor according to claim 8, characterized in that, The beam splitting system further includes: a light limiting component; the light limiting component includes: a rectangular aperture arranged between the collimating lens and the cylindrical focusing lens, and is used to receive the fourth light beam and adjust 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 for the image side and the object side.

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