CN115665563A

CN115665563A - Optical measurement system and imaging method based on optical measurement system

Info

Publication number: CN115665563A
Application number: CN202211602684.3A
Authority: CN
Inventors: 张琥杰; 张和君; 刘怡; 章智伟
Original assignee: Chotest Technology Inc
Current assignee: Chotest Technology Inc
Priority date: 2022-12-14
Filing date: 2022-12-14
Publication date: 2023-01-31
Anticipated expiration: 2042-12-14
Also published as: CN116828318A; CN116744123A; CN115665563B; CN116744123B; CN116828318B

Abstract

The optical measurement system comprises an illumination module, a light splitting module, a scanning module, an imaging module and an image processing module, the multi-hole plate comprises a mounting area and a scanning area arranged around the mounting area, the scanning area comprises a spiral area with a plurality of Archimedes spirals, the through light hole groups forming the Archimedes spirals are distributed in a rotational symmetry mode around the center of the multi-hole plate, the spiral area comprises a plurality of groups of through light hole arrays arranged periodically in a mode of surrounding the center of the multi-hole plate, and the spiral area comprises at least three groups of through light hole arrays. Therefore, the multi-hole plate can perform multiple imaging in one rotation cycle according to different surface reflectivity of the object to be measured, and the optical measurement system and the imaging method based on the optical measurement system can perform multi-frame fusion on a plurality of imaged images with different exposure ranges to obtain a larger dynamic range.

Description

Optical measurement system and imaging method based on optical measurement system

Technical Field

The present disclosure relates generally to the smart manufacturing equipment industry, and more particularly to an optical measurement system and an imaging method based on the optical measurement system.

Background

At present, optical microscopy is widely applied to various fields of scientific and technical research, but the reconstruction of three-dimensional morphology of an object with certain thickness cannot be realized by common optical microscopy. With the continuous development of the microscopic technology in recent years, the confocal microscopic technology becomes one of the important technologies in the optical microscopic field, has the characteristics of high precision, high resolution, non-contact and unique axial tomography, can realize the reconstruction of the three-dimensional shape of an object to be detected, and is widely applied to the fields of micro-nano detection, precise measurement, life science research and the like.

In the prior art, the parallel scanning confocal microscopic detection technology based on the Nipkow porous plate (Nipkow porous plate) has the advantages of simple structure, easy realization, low cost, high image quality and the like.

However, when the conventional Nipkow porous disc with a confocal pinhole is applied to a confocal microscope, the conventional Nipkow porous disc is usually designed to rotate for one circle to enable the confocal microscope to image a sample once, so that for a sample with weak surface reflectivity or strong and weak surface reflectivity, in a single imaging of the confocal microscope, an area with weak surface reflectivity of the sample may have a problem of insufficient exposure, and an image with a high dynamic range cannot be obtained.

Disclosure of Invention

The present disclosure is made in view of the above-mentioned prior art, and an object of the present disclosure is to provide an optical measurement system and an imaging method based on the optical measurement system, which can perform multiple imaging within one rotation cycle according to the difference of the surface reflectivity of an object and perform multi-frame fusion on a plurality of images with different exposure ranges to form one high dynamic range image.

To this end, a first aspect of the present disclosure provides an optical measurement system including an illumination module, a spectroscopy module, a scanning module, an imaging module, and an image processing module; the illumination module is used for emitting an illumination light beam; the light splitting module is arranged between the illumination module and the scanning module and is configured to receive a reflected light beam from the scanning module and reflect the reflected light beam to the imaging module; the scanning module comprises a multi-hole disc and a driving device for driving the multi-hole disc to rotate, the multi-hole disc is arranged along the propagation direction of an illumination light beam, the scanning module is configured to receive the illumination light beam transmitted through the light splitting module, emit the illumination light beam to an object to be measured and receive a reflected light beam from the object to be measured and emit the reflected light beam to the light splitting module, the multi-hole disc comprises a mounting area and a scanning area, the mounting area is positioned in the center of the multi-hole disc and is used for mounting the driving device for driving the multi-hole disc to rotate, the scanning area is arranged around the mounting area, the scanning area comprises a spiral area with a plurality of Archimedes spirals, the groups of light through holes forming the Archimedes spirals are distributed in rotational symmetry around the center of the multi-hole disc, the spiral area comprises a plurality of light through hole arrays which are periodically arranged around the center of the multi-hole disc, and the spiral area comprises at least three groups of the light through hole arrays; the imaging module is configured to receive a reflected light beam from the object to be measured and reflected by the light splitting module for imaging, the porous plate rotates for at least one unit period to enable the imaging module to image for the first time, the porous plate continues to rotate for at least two unit periods to enable the imaging module to image for the second time, the unit period is an angle of a group of light-passing hole arrays surrounding the center of the porous plate, and the periods of the multiple rotations of the porous plate back and forth are different; the image processing module is used for receiving the images imaged by the imaging module at least twice and fusing at least two images with different exposure ranges into an image with a high dynamic range.

In the first aspect of the present disclosure, the optical measurement system can perform multiple imaging of the multi-hole plate when the multi-hole plate rotates one cycle by periodically arranging the light-transmitting hole arrays around the center of the multi-hole plate, and the object to be measured can be completely scanned for at least two different exposure times by arranging at least three sets of light-transmitting hole arrays in the spiral region; the multi-hole disc rotates for at least one unit period, so that the first complete scanning of first exposure time can be carried out on a region to be detected of an object to be detected, a first image is formed in the imaging module, the multi-hole disc continues to rotate for at least two unit periods, and the periods of the multi-hole disc rotating for multiple times are different from each other, so that the second complete scanning of second exposure time different from the first exposure time can be carried out on the region to be detected of the object to be detected, the second image is formed in the imaging module, then, at least two images with different exposure ranges can be fused into an image with a high dynamic range through the image processing module, and therefore, the image with a high dynamic range can be conveniently processed.

In addition, in the optical measurement system according to the first aspect of the present disclosure, optionally, the porous plate further includes a peripheral region surrounding the scanning region, the scanning region further includes a tolerance region and a wide-field region for wide-field imaging, and a plating region is provided in the peripheral region corresponding to the wide-field region. Therefore, the object to be measured can be conveniently observed according to the wide field region, the object to be measured or the region to be measured of the object to be measured can be conveniently switched between wide field observation and confocal scanning through synchronous triggering of the coating region, and the tolerance region can be used as a time delay region generated by starting of optical signals and receiving of imaging.

Further, in the optical measurement system according to the first aspect of the present disclosure, optionally, the shape of the multi-hole plate is a circle, the shape of the scanning region and the peripheral region is a circle, and the shape of the spiral region, the tolerance region, the wide field region, and the plating region is a fan ring. Therefore, the scanning region and the peripheral region can be conveniently configured on the circular porous disc, and the spiral region, the tolerance region, the wide field region and the plating layer region can be conveniently configured.

Further, in the optical measuring system according to the first aspect of the present disclosure, optionally, each group of the light passing holesThe array is at an angle theta around the center of the multi-well plate, and the optical measurement system selects the spiral regions to rotate x in sequence ₁ θ、x ₂ θ、……、x _m Time of theta as exposure time, x ₁ θ+x ₂ θ+……+x _m θ≤360°，x ₁ ，x ₂ ，……，x _m Are respectively positive integers and are not equal to each other; the image processing module is used for fusing m images with different exposure ranges into an image with a high dynamic range. Therefore, the object to be measured can be completely scanned for m times in different exposure time within one rotation circle of the porous plate, and the image processing module can fuse m images in different exposure ranges into one image with a high dynamic range.

Further, in the optical measuring system according to the first aspect of the present disclosure, optionally, the illumination module includes a light source for emitting an illumination light beam and a first polarization unit for converting a polarization state of the illumination light beam from natural light to linearly polarized light. Therefore, the light source can conveniently emit the illumination light beams, and the first polarization unit can conveniently convert the polarization state of the illumination light beams into linearly polarized light from natural light.

In addition, in the optical measurement system according to the first aspect of the present disclosure, optionally, the scanning module further includes a second polarization unit and a microscope objective, and the illumination light beam reaches the object to be measured and is reflected by the object to be measured to form a reflected light beam through the porous plate, the second polarization unit, and the microscope objective in sequence. Therefore, the second polarization unit can conveniently change the polarization directions of the illuminating light beam and the reflected light beam, and the microscope objective can conveniently amplify and the like the object to be detected.

In addition, in the optical measurement system according to the first aspect of the present disclosure, optionally, the imaging module includes a sensing unit, a third polarization unit disposed between the sensing unit and the light splitting module, and the sensing unit is configured to receive a reflected light beam transmitted through the third polarization unit. Therefore, the sensing unit can image the object to be detected, and the third polarization unit can conveniently change the polarization directions of the illuminating light beams and the reflected light beams.

In addition, in the optical measurement system according to the first aspect of the present disclosure, optionally, the light passing holes located in the radial direction of the porous plate have the same pitch, and the light passing holes located in the circumferential direction of the porous plate have the same radial pitch; the polar coordinate expression of the light through hole on the spiral area is as follows:

wherein r is the distance from the center of the light through hole to the center of the porous plate, n is the nth light through hole on the single spiral, r ₁ The distance from the center of the porous disc to the center of the light through hole at the beginning of the single spiral, delta r is the value of increasing unit angle r of the spiral along the radial direction of the porous disc, and delta theta is the argument increment of the adjacent light through holes of the single spiral; the distance d between the adjacent light through holes of the single spiral satisfies the formula:

and the distance between the adjacent light through holes of the single spiral is equal to the distance between the light through holes in the radial direction of the multi-hole disc. Therefore, the arrangement mode of the light through holes in the spiral area can be conveniently designed, and the light through holes can be uniformly and compactly arranged in the whole scanning area.

In addition, in the optical measurement system according to the first aspect of the present disclosure, optionally, the central axis of the porous plate and the predetermined direction have a first predetermined included angle greater than 0 °, and the predetermined direction is a direction perpendicular to a carrying platform carrying the object to be measured. Thereby, the porous plate can be disposed obliquely.

A second aspect of the present disclosure provides an imaging method based on an optical measurement system, which includes the following steps: a preparation step of preparing an illumination module, a spectroscopy module, a scanning module, an imaging module, and an image processing module; a configuration process of turning on the illumination module for emitting an illumination beam; disposing the spectroscopy module between the illumination module and the scanning module and configured to receive a reflected beam from the scanning module and reflect the reflected beam to the imaging module; arranging the multi-hole disc along the propagation direction of the illumination light beam, and configuring the scanning module to receive the illumination light beam transmitted through the light splitting module and emit the illumination light beam to an object to be measured and receive a reflected light beam from the object to be measured and emit the reflected light beam to the light splitting module; the imaging module is configured to receive a reflected light beam from the object to be measured and reflected by the light splitting module for imaging; the multi-hole plate comprises a mounting area and a scanning area, the mounting area is positioned in the center of the multi-hole plate and is used for mounting a driving device for driving the multi-hole plate to rotate, the scanning area is arranged around the mounting area and comprises a spiral area with a plurality of Archimedes spiral lines, light through hole groups forming the Archimedes spiral lines are distributed in a rotational symmetry mode around the center of the multi-hole plate, the spiral area comprises a plurality of groups of light through hole arrays which are arranged periodically in a mode of surrounding the center of the multi-hole plate, and the spiral area comprises at least three groups of the light through hole arrays; an imaging step of rotating the porous plate for at least one unit period by driving the driving device and imaging the imaging module for the first time, and continuing to drive the driving device to rotate the porous plate for at least two unit periods by which the group of light transmission hole arrays surround the center of the porous plate and imaging the imaging module again, wherein the unit periods of the multiple rotations of the porous plate are different; and the image processing module is used for receiving the images imaged by the imaging module at least twice and fusing at least two images with different exposure ranges into an image with a high dynamic range.

In the second aspect of the present disclosure, the optical measurement system can perform multiple imaging of the multi-well plate when the multi-well plate rotates one cycle by periodically arranging the clear hole arrays around the center of the multi-well plate, and the object to be measured can be completely scanned for at least two different exposure times by arranging at least three sets of clear hole arrays in the spiral region; the multi-hole disc rotates for at least one unit period, so that the first complete scanning of first exposure time can be carried out on a region to be detected of the object to be detected, a first image is formed in the imaging module, the multi-hole disc continues to rotate for at least two unit periods, and the periods of the multi-hole disc rotating for multiple times are different from each other, so that the second complete scanning of second exposure time different from the first exposure time can be carried out on the region to be detected of the object to be detected, the second image is formed in the imaging module, then, at least two images with different exposure ranges can be fused into an image with a high dynamic range through the image processing module, and therefore, the image with a high dynamic range can be conveniently processed.

According to the present disclosure, an optical measurement system and an imaging method based on the optical measurement system can be provided, in which a multi-hole plate is imaged multiple times in one rotation cycle according to the difference of the surface reflectivity of an object to be measured, and multiple imaged images with different exposure ranges are subjected to multi-frame fusion to form one high dynamic range image.

Drawings

Embodiments of the present disclosure will now be explained in further detail by way of example only with reference to the accompanying drawings.

Fig. 1 is a schematic diagram showing a hardware configuration of an optical measurement system according to an embodiment of the present disclosure.

Fig. 2 is a functional block diagram illustrating an optical measurement system according to an embodiment of the present disclosure.

Fig. 3 is a schematic diagram illustrating optical path measurement of an optical measurement system according to an embodiment of the present disclosure.

Fig. 4 is a schematic external view showing a porous plate according to an embodiment of the present disclosure.

Fig. 5 is a schematic view showing a region division of a porous plate according to an embodiment of the present disclosure.

Fig. 6 is a schematic diagram showing an example of multiple imaging of the optical measurement system according to the embodiment of the present disclosure within one rotation circle of the porous plate.

Fig. 7 is an enlarged schematic view illustrating a region a in fig. 5.

Fig. 8 is a flowchart illustrating one example of an optical measurement system-based imaging method according to an embodiment of the present disclosure.

Fig. 9 is a flowchart illustrating another example of an imaging method based on an optical measurement system according to an embodiment of the present disclosure.

Detailed Description

Hereinafter, preferred embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In the following description, the same components are denoted by the same reference numerals, and redundant description thereof is omitted. In addition, the drawings are only schematic, and the ratio of the sizes of the components to each other, the shapes of the components, and the like may be different from actual ones.

It is noted that the terms "comprises," "comprising," and "having," and any variations thereof, in this disclosure, for example, a process, method, system, article, or apparatus that comprises or has a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include or have other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

High Dynamic Range Imaging (HDRI or HDR) is generally applied to the fields of computer graphics and motion picture photography, and is a group of techniques for realizing a larger Dynamic Range of exposure than that of a general digital image technique. Different from HDR in the field of computer graphics or cinematography, in view of the particularity of confocal imaging, the full scanning of the object to be measured in multiple times of different exposure time can be carried out within one circle of rotation of the porous disc, each scanning can form a full image of the object to be measured in a field range, and finally, a multi-frame fusion technology is applied, so that the optical measurement system can form an image with a high dynamic range.

Fig. 1 is a schematic diagram showing a hardware configuration of an optical measurement system according to an embodiment of the present disclosure. Fig. 2 is a functional block diagram illustrating an optical measurement system according to an embodiment of the present disclosure.

Referring to fig. 1 and 2, the present disclosure provides an optical measurement system that can be used to measure and reconstruct the three-dimensional topography of a test object 6. In the present disclosure, the optical measurement system may also be referred to as an optical three-dimensional measurement system, confocal measurement system or confocal measurement system, or simply measurement system.

In the present embodiment, the optical measurement system may include an illumination module 2, a spectroscopy module 3, a scanning module 1, an imaging module 4, and an image processing module 5.

In some examples, the optical measurement system may include the microscope and the upper computer shown in fig. 1. In some examples, the illumination module 2, the light splitting module 3, the scanning module 1, and the imaging module 4 may be disposed in a microscope, the image processing module 5 may be disposed in an upper computer, the microscope may be used to observe and form an image of the object 6 to be measured, the formed image of the object 6 to be measured may be uploaded or copied to the upper computer, and processed by the image processing module 5 in the upper computer.

In other examples, the microscope itself may be provided with the image processing module 5. Thus, the image formed by the imaging module 4 can be processed conveniently and synchronously.

In some examples, illumination module 2 may be used to provide illumination beam L1 for a confocal measurement system.

In some examples, the light splitting module 3 may be disposed between the illumination module 2 and the scanning module 1 and configured to receive the reflected light beam L1 'from the scanning module 1 and reflect the reflected light beam L1' to the imaging module 4.

In some examples, the scanning module 1 may include a multi-hole plate 10 and a driving device for driving the multi-hole plate 10 to rotate, the multi-hole plate 10 may be disposed along a propagation direction of the illumination light beam L1, and the scanning module 1 may be configured to receive the illumination light beam L1 transmitted through the light splitting module 3 and emit the illumination light beam L1 to the object 6 and receive the reflected light beam L1 'from the object 6 and emit the reflected light beam L1' to the light splitting module 3.

Referring to fig. 3, the illumination light beam L1 is emitted by the illumination module 2 and then reaches the light splitting module 3, the illumination light beam L1 can penetrate through the light splitting module 3 and irradiate the object to be measured 6 through the scanning module 1, the object to be measured 6 reflects the illumination light beam L1 to form a reflected light beam L1', the reflected light beam L1' can reach the light splitting module 3 through the scanning module 1 and can be reflected to the imaging module 4 by the light splitting module 3, and the imaging module 4 can receive the reflected light beam L1' to obtain the surface information of the region to be measured of the object to be measured 6.

In some examples, the illumination module 2 may include a light source 21 and a first polarization unit 22. Wherein the light source 21 may be adapted to emit an illumination light beam L1. The first polarization unit 22 can convert the polarization state of the illumination beam L1 from the natural light to the linearly polarized light.

In some examples, the light source 21 can be an LED or SLED, and the illumination beam L1 emitted by the light source 21 can be visible light or ultraviolet light.

In some examples, the first polarizing unit 22 may be a polarizer.

In this embodiment, the illumination module 2 may further include a first reflection unit 23, and the first reflection unit 23 may be disposed on a side of the first polarization unit 22 away from the light source 21. In other words, the first polarization unit 22 may be disposed between the light source 21 and the first reflection unit 23. In this case, the illumination light beam L1 emitted via the light source 21 can be transmitted through the first polarization unit 22 and reach the first reflection unit 23 to be reflected by the first reflection unit 23 to the spectral module 3.

In some examples, the lighting module 2 may further include a first lens unit 24 disposed between the light source 21 and the first reflection unit 23. The first lens unit 24 may be configured to collimate the illumination light beam L1. Thereby, the illumination light beam L1 can be made into parallel light after passing through the first lens unit 24.

In some examples, the first lens unit 24 may be a collimating lens. For example, a glass aspherical positive focus lens may be used. In some examples, aspheric lenses may be effective in improving light energy utilization. In other examples, the first lens unit 24 may also be a cemented lens.

In the present embodiment, the lighting module 2 may further include a second lens unit 25 disposed between the light source 21 and the first reflection unit 23. The second lens unit 25 may be configured to adjust the collimated illumination light beam L1 such that the position of the image of the light source 21 is located at the back focal plane of the microscope objective 13. In this case, the position of the image of the light source 21 can be regarded as being located at the entrance pupil of the microscope objective 13, whereby the illumination light beam L1 can be uniformly irradiated to the surface of the object 6.

As described above, the lighting module 2 may include the first reflecting unit 23. In some examples, the first reflection unit 23 may be used to reflect the illumination light beam L1 to the light splitting module 3. In some examples, the illumination module 2 may not include the first reflection unit 23, and the illumination light beam L1 may directly reach the light splitting module 3 via the first lens unit 24, the second lens unit 25, and the first polarization unit 22 in sequence.

In some examples, the light splitting module 3 may be configured to reflect a portion of the illumination light beam L1 to an inner wall of the microscope and transmit a portion of the illumination light beam L1 to the scanning module 1.

In some examples, the light splitting module 3 may be disposed between the illumination module 2 and the scanning module 1, and the illumination light beam L1 reaches the scanning module 1 after being transmitted by the light splitting module 3. In other words, the scanning module 1 may be configured to receive the illumination light beam L1 transmitted through the light splitting module 3.

In some examples, the scanning module 1 may further comprise a second polarizing unit 12 and a microscope objective 13. The illumination light beam L1 may sequentially reach the object 6 to be measured via the multi-hole plate 10, the second polarizing unit 12, and the microscope objective 13 and be reflected by the object 6 to form a reflected light beam L1'. In other words, the multi-hole plate 10 having the light passing hole 1111, the second polarization unit 12, and the micro-objective lens 13 may be sequentially disposed along the propagation direction of the illumination light beam L1.

In some examples, the plurality of clear holes 1111 may be uniformly arranged in the multi-hole plate 10 in the manner of the archimedean spiral 1110. When the illumination light beam L1 reaches the multi-hole plate 10, a part may be transmitted through the multi-hole plate 10 via the light-transmitting holes 1111 to reach the second polarization unit 12 (hereinafter, referred to as the illumination light beam L1 continuously), and a part may be reflected by the multi-hole plate 10 to form a stray light beam.

In some examples, the multi-hole plate 10 may be rotated to change the position of the light passing hole 1111 so that the illumination light beam L1 reaches each region to be measured of the object 6. This enables complete scanning of the object 6.

In some examples, the porous disk 10 having the light passing holes 1111 may be a Nipkow porous disk.

In some examples, the multi-well plate 10 may be disposed on the scan module 1 in parallel with a supporting platform for supporting the object 6. Thereby, the illumination light beam L1 can enter the scan module 1 through the light passing hole 1111.

In some examples, the central axis of the porous disc 10 may have a first preset angle greater than 0 ° from the preset direction D1. In other words, the porous plate 10 may be obliquely disposed. Preferably, the inclination direction of the porous plate 10 may be set as shown in fig. 3. In this case, the illumination light beam L1 can also enter the scanning module 1 through the light-passing hole 1111, and when part of the illumination light beam L1 is reflected by the multi-hole plate 10 to form a stray light beam, the propagation direction of the stray light beam can propagate away from the imaging module 4, which can reduce the possibility that the stray light beam enters the imaging module 4 to affect the imaging of the object 6 to be measured.

In some examples, the preset direction D1 may be a direction perpendicular to a carrying platform carrying the object 6 to be tested.

In some examples, the second polarization unit 12 may be a 1/4 wave plate. In this case, the illumination light beam L1 and the reflected light beam L1' pass through the 1/4 wave plate in sequence, which can rotate the reflected light beam L1' emitted from the scanning module 1 by 90 ° relative to the polarization direction of the illumination light beam L1, so that the reflected light beam L1' on the surface of the object 6 to be measured can be transmitted through the third polarization unit 42 and received by the sensing unit 41 (described later). In some examples, the second polarization unit 12 may be disposed at 45 ° to the preset direction D1.

In some examples, the imaging module 4 may include a sensing unit 41, and a third polarization unit 42 disposed between the sensing unit 41 and the light splitting module 3. The reflected beam L1' may reach the sensing unit 41 via the third polarization unit 42 after being reflected by the light splitting module 3. In other words, the sensing unit 41 may be configured to receive the reflected light beam L1' transmitted through the third polarization unit 42.

In some examples, the sensing unit 41 may be a CCD or CMOS camera. The third polarization unit 42 may be a polarizing plate orthogonal to the polarization direction of the first polarization unit 22. Thus, the illumination light beam L1 transmitted through the first polarization unit 22 may be absorbed by the third polarization unit 42 without being transmitted by the third polarization unit 42.

In some examples, the imaging module 4 may further include a third lens unit 43 disposed between the sensing unit 41 and the third polarization unit 42. In some examples, the third lens unit 43 may be a relay lens. The third lens unit 43 may be used to focus the reflected light beam L1' to the sensing unit 41.

In some examples, the scanning module 1 may further include a sleeve lens 14 disposed between the multi-well plate 10 and the microscope objective 13. The telescopic lens 14 may be configured to adjust the illumination light beam L1 such that the position of the image of the light source 21 is located at the entrance pupil of the microscope objective 13, i.e. the back focal plane of the microscope objective 13. Thereby, the illumination light beam L1 can be uniformly irradiated to the surface of the object 6.

In some examples, the sleeve lens 14 may be a single lens. In other examples, the sleeve lens 14 may be a combination of multiple lenses.

In some examples, microscope objective 13 may be an infinity microscope objective. In this case, if the region to be measured of the object 6 is located at the focal plane of the microscope objective 13, the reflected light beam L1' reflected by the region to be measured can be changed into parallel light after exiting through the microscope objective 13.

In some examples, a driving device may be installed at the installation region 120 of the porous plate 10. The driving means may be used to drive the porous plate 10 to rotate and/or move.

In some examples, the driving device can rotate the multi-hole plate 10 at a speed precisely matched with the sampling frequency of the imaging module 4, and also matched with the longitudinal driving speed of the microscope objective 13 in the microscope, so that the imaging module 4 can acquire continuous and complete images of the region to be measured on the object 6.

Fig. 4 is a schematic view showing an external appearance of a porous plate according to an embodiment of the present disclosure. Fig. 5 is a schematic view showing a region division of a porous plate according to an embodiment of the present disclosure.

Referring to fig. 4 and 5, the multi-well plate 10 according to the present embodiment may be used in the above-described optical measurement system, which may be used to measure the object 6 to reconstruct the three-dimensional topography of the object 6. For example, the three-dimensional shape of the object 6 can be reconstructed by measuring the height information of each area of the object 6.

In this embodiment, the multi-well plate 10 may include a scanning region 110 and a mounting region 120. The scanning region 110 may be used to scan and image the object 6, and the multi-well plate 10 may be provided with a driving device through the mounting region 120.

In some examples, the mounting region 120 may be located at the center O of the porous disk 10. In some examples, the mounting region 120 may pass through a plurality of mounting holes reserved to connect with a driving device, which may be used to drive the porous plate 10 to rotate and/or move.

In some examples, the scanning area 110 may be arranged around the mounting area 120.

In the present embodiment, the scanning area 110 may include a spiral area 111 having several archimedean spirals 1110 (see fig. 5). In some examples, the sets of light passing holes forming the archimedean spiral 1110 may be distributed with rotational symmetry around the center O of the porous disk 10.

In some examples, the spiral region 111 may include a plurality of sets of clear hole arrays 1120 arranged periodically in a manner to surround the center O of the porous plate 10.

In some examples, the spiral region 111 may include at least three sets of clear hole arrays 1120.

In the present disclosure, by periodically arranging the clear hole arrays 1120 in such a manner as to surround the center O of the multi-well plate 10, the optical measurement system can be subjected to multiple imaging when the multi-well plate 10 is used for the optical measurement system and is rotated one revolution thereof. By configuring at least three sets of light-transmitting hole arrays 1120 in the spiral region 111, the object 6 to be measured can be completely scanned with at least two different exposure times, for example, the spiral region 111 rotates for one unit period to form one image, and the spiral region 111 continues to rotate for two unit periods to form one image, so that the exposure time during the second imaging is twice as long as that of the first imaging, and the complete scanning of the object 6 to be measured during the second imaging can be ensured. Thus, by arranging at least three sets of clear hole arrays 1120 in the spiral region 111, the object 6 can be completely scanned for a plurality of (at least two) different exposure times within one rotation cycle of the multi-well plate 10.

In some examples, the multi-well plate 10 may also include a peripheral region 130 surrounding the scanning region 110. In some examples, the scan region 110 may also include a wide-field region 112 for wide-field imaging. In some examples, a plating region 131 may be provided at the peripheral region 130 corresponding to the wide field region 112. In this case, the object 6 to be measured can be conveniently observed according to the wide field region 112, and the object 6 to be measured or the region to be measured of the object 6 to be measured can be conveniently switched between wide field observation and confocal scanning by the synchronous triggering of the plating layer region 131.

In some examples, the wide field area 112 may be provided as a transparent area. Thus, the position of the object 6 or the area to be measured of the object 6 can be easily found.

In some examples, the shape of the porous disk 10 may be circular.

In some examples, the porous disk 10 may be a Nipkow porous disk (nipkov porous disk). In some examples, the Nipkow porous disc may also be referred to as a Nipkow disk.

In some examples, the scanning region 110 and the peripheral region 130 may be shaped as circular rings. In some examples, the spiral region 111, the wide field region 112, and the plating region 131 may be shaped as a fan ring.

In some examples, referring to fig. 5, the unit period may be an angle at which the group of clear hole arrays 1120 surrounds the center O of the porous plate 10, and may be represented as θ. It is understood that the sum of the unit periods is equal to or less than 360 °, i.e., k θ is equal to or less than 360 ° if the spiral region 111 has k sets of light passing hole arrays 1120.

In some examples, if each set of the light passing hole arrays 1120 surrounds the center O of the multi-hole plate 10 at an angle θ (i.e. the unit period is θ), the optical measurement system may select the spiral region 111 to rotate x in turn ₁ θ、x ₂ θ、……、x _m The time of theta is taken as the exposure time, and x is required to be satisfied ₁ θ+x ₂ θ+……+x _m θ≤360°，x ₁ ，x ₂ ，……，x _m Are respectively positive integers and are not equal to each other. The image processing module 5 may be configured to fuse m images with different exposure ranges into a high dynamic range image. Therefore, the object 6 can be completely scanned for m times with different exposure times within one rotation circle of the multi-hole plate 10, and the image processing module 5 can fuse m images with different exposure ranges into one image with a high dynamic range.

Referring to fig. 6, in some examples, the porous disk 10 may also include a tolerance region 1112.

In some examples, the multi-aperture plate 10 may reserve a portion of the area in the spiral region 111 as a tolerance region 1112 for the time delay resulting from the turning on and imaging reception of the light signal (which may be the illumination light beam L1).

In some examples, the angle of each set of clear aperture arrays 1120 around the center O of the multi-aperture plate 10 may be 30 °, and one unit period θ of rotation of the spiral region 111 in the optical measurement system may be 30 °. At this time, the spiral region 111 may have at least 10 sets of the clear aperture array 1120. In some examples, at this point, the spiral region 111 may have 11 sets of clear aperture arrays 1120, and the last set of clear aperture arrays 1120 may serve as the tolerance region 1112.

In some examples, the optical measurement system may select as the exposure time the time during which the spiral region 111 rotates by 30 °, 60 °, 90 °, 120 ° in sequence, i.e., when the unit exposure time is t ₀ The confocal measurement system can select t ₀ 、2t ₀ 、3t ₀ 、4t ₀ As the exposure time.

In optical imaging, as shown in fig. 6, the optical measurement system may choose to rotate the spiral region 111 30 ° to bring the imaging module 4 into a first image 410, as a first step. This corresponds to one exposure of the region of the test object 6.

In a second step, the optical measurement system may select the helical region 111 to rotate 60 ° to bring the imaging module 4 into a second image 420. This corresponds to exposing the region of the test object 6 twice.

In a third step, the optical measurement system may select that the spiral region 111 is rotated by 90 ° to bring the imaging module 4 into a third image 430. This corresponds to three exposures of the region of the specimen 6 to be measured.

Fourth, the optical measurement system may select the spiral region 111 to rotate 120 ° to make the imaging module 4 to form a fourth image 440. This corresponds to four exposures of the region of the test object 6.

Thus, the optical measurement system can perform 4 complete scans with different exposure times on the object 6 within one rotation of the porous plate 10, and can perform sufficient exposure step by step for each region where the surface reflectance of the object 6 decreases by increasing the exposure time step by step in sequence.

In some examples, the time interval between imaging of the above steps may be none or small.

Of course, in other examples, the optical measurement system may select the exposure time as the time for which the spiral region 111 is sequentially rotated by 30 °, 60 °, and 90 °. In other examples, the optical measurement system may select the exposure time as the time for which the spiral region 111 is sequentially rotated by 60 °, 90 °, and 120 °. In other examples, the optical measurement system may select the exposure time as the time for which the spiral region 111 rotates by 30 °, 60 °, 120 ° in sequence. In other examples, the optical measurement system may select the exposure time as the time for which the spiral region 111 is sequentially rotated by 30 °, 90 °, 120 °.

Of course, in other examples, the optical measurement system may select the exposure time as the time for which the spiral region 111 is sequentially rotated by 90 °, 60 °, and 30 °. In other examples, the optical measurement system may select the exposure time as the time for which the spiral region 111 is sequentially rotated by 120 °, 90 °, 60 °. In other examples, the optical measurement system may select the exposure time as the time for which the spiral region 111 rotates by 120 °, 60 °, 30 ° in sequence. In other examples, the optical measurement system may select the exposure time as the time for which the spiral region 111 is sequentially rotated by 120 °, 90 °, 30 °.

It will be appreciated that the angle occupied by the spiral region 111 may not be greater than 360. In the above example, when the unit period is 30 °, the sum of the tolerance region 1112 and the wide-field region 112 may not be larger than 60 °. In some examples, 10 ° to 50 ° may be selected from 60 ° as the tolerance region 1112, and correspondingly, the remaining 50 ° to 10 ° may be selected as the wide field region 112.

In other examples, the unit period may also be 10 °, 20 °, 40 °, 50 °, 60 °, etc.

In some examples, when the unit period is 10 °, the optical measurement system may select, as the exposure time, a time during which the spiral region 111 is sequentially rotated by 10 °, 20 °, 30 °, 40 °, 50 °, 60 °, 70 °. In some examples, when the unit period is 10 °, the optical measurement system may select a time during which the spiral region 111 is sequentially rotated by 10 °, 30 °, 50 °, and 70 ° as the exposure time. In some examples, when the unit period is 10 °, the optical measurement system may select a time for which the spiral region 111 is sequentially rotated by 10 °, 40 °, 50 °, 70 ° as the exposure time.

In some examples, when the unit period is 20 °, the optical measurement system may select, as the exposure time, a time during which the spiral region 111 is sequentially rotated by 20 °, 40 °, 60 °, 80 °, 120 °. In some examples, when the unit period is 20 °, the optical measurement system may select a time during which the spiral region 111 is sequentially rotated by 20 °, 60 °, 120 ° as the exposure time. In some examples, when the unit period is 20 °, the optical measurement system may select a time for which the spiral region 111 is sequentially rotated by 20 °, 40 °, 120 ° as the exposure time.

It should be noted that the exposure time may be selected by keeping the period of the multiple rotations of the porous plate 10 different.

It can be understood that the unit period needs to be adaptively selected according to the surface reflectivity of the corresponding object to be measured 6, and an excessively short exposure time may result in an excessively low image gray level and an ineffective signal, and an excessively long exposure time may result in an image gray level saturation and an ineffective signal.

Fig. 7 is an enlarged schematic view illustrating a region a in fig. 5.

Referring to fig. 7, in some examples, the clear aperture 1111 may be a circular pinhole.

In some examples, the spacing of the light passing holes 1111 in the radial direction of the porous plate 10 may be equal. In some examples, the spoke spacing of the light passing holes 1111 in the circumferential direction of the porous plate 10 may be equal. This allows the light passing holes 1111 to be uniformly arranged over the entire scanning region 110.

In some examples, the polar expression of the clear hole 1111 in the spiral region 111 may be:

wherein r is the distance from the center (circle center) of the light through hole 1111 to the center O of the porous plate 10, n is the nth light through hole 1111 in the single spiral ₁ The distance from the center O of the porous plate 10 to the center of the initial light-passing hole 1111 of one spiral, Δ r is the value of the unit angle r of increase of the spiral, and Δ θ is the argument increment of the adjacent light-passing hole 1111 of the single spiral. Therefore, the arrangement mode of the light through holes 1111 in the spiral region 111 can be conveniently designed.

In some examples, the initial clear hole 1111 may be one clear hole 1111 near the center O of the porous plate 10 forming one spiral. In this case, other light passing holes 1111 can be conveniently designed or arranged with reference to the initial light passing hole 1111.

In some examples, the clear holes 1111 may have a diameter of 0.010-0.050mm, and the spacing between the clear holes 1111 in the radial direction of the multi-plate 10 may be 0.10-0.50mm. Meanwhile, the diameter of the light passing holes 1111 and the interval between the light passing holes 1111 located in the radial direction of the multi-hole plate 10 are selected to be suitable, that is, the ratio thereof is appropriate.

It can be understood that the larger the diameter of the light through hole 1111 is, the better the system light effect is, but the longitudinal resolution will be reduced, and conversely, the smaller the diameter of the light through hole 1111 is, the longitudinal resolution can be improved, but the system light effect will be reduced; the smaller the ratio of the space of each light through hole 1111 to the diameter of the light through hole 1111 is, the better the system light efficiency is, but the light crosstalk phenomenon between the adjacent light through holes 1111 is easy to occur, otherwise, the larger the ratio of the space of each light through hole 1111 to the diameter of the light through hole 1111 is, the worse the system light efficiency is, but the light crosstalk phenomenon between the adjacent light through holes 1111 can be avoided.

Referring to fig. 7, in some examples, more preferably, the diameter of the light passing holes 1111 may be 0.025mm, and the interval between the light passing holes 1111 located in the radial direction of the porous plate 10 may be 0.25mm. In this case, by setting the ratio of the pitch of the light passing holes 1111 to the diameter of the light passing holes 1111 to 10.

In other examples, the diameter of the light passing hole 1111 may also be 0.06mm, 0.07mm, 0.08mm, 0.09mm, and the like. In other examples, the distance between the light-passing holes 1111 located in the radial direction of the porous plate 10 may be 0.6mm, 0.7mm, 0.8mm, 0.9mm, or the like. It is understood that the diameter of the light-transmitting holes 1111 and the distance between the radial light-transmitting holes 1111 are selected to be suitable, and the arrangement of the light-transmitting holes 1111 should be as compact and uniform as possible, thereby improving the imaging quality and the imaging efficiency.

In some examples, the spacing d between adjacent clear apertures 1111 of a single spiral may satisfy the formula:

. In some examples, the spacing between adjacent clear holes 1111 of the single spiral may be equal to the spacing of the respective clear holes 1111 in the radial direction of the multi-hole plate 10. In some examples of the method of the present invention,

. It is understood that when the distance between the light passing holes 1111 in the radial direction of the porous plate 10 is 0.25mm, d is slightly larger than 0.25mm. In this case, by making d closer to 0.25mm, the arrangement of the light passing holes 1111 can be made more uniform and compact, thereby making it possible to make a map of the region to be measured of the object 6 to be measuredThe image is more uniform and the imaging effect is better.

In this embodiment, the diameter of each light-passing hole 1111 and the distance between adjacent light-passing holes 1111 in the spiral region 111 should be determined according to the magnification of the microscope objective 13 to which the spiral region 111 is to be adapted, and the distance between the diameter of each light-passing hole 1111 and the adjacent light-passing holes 1111 should be sized so that the optical measurement system has the best resolution and accuracy when the microscope objective 13 corresponding to the optical measurement system is magnified.

As an example, a design process of arranging the light passing holes 1111 on the first archimedean spiral in a polar coordinate system and calculating the position of the center of the circle thereof will be described below.

In this embodiment, a certain point on the first archimedean spiral may be located in the same radial direction as the initial point of the second archimedean spiral, i.e. with the same argument, and be 250 μm apart, so that the following relationship holds:

wherein m is a positive integer.

From which can be calculated

。

In the present embodiment, the interval between the adjacent light passing holes 1111 of the single spiral may be

And satisfy

. The effective clear hole 1111 area used in practice has a radial extent of about 6mm. Because the distance between the adjacent light-passing holes 1111 increases as the light-passing holes 1111 are far away from the center O of the multi-hole plate 10, the radial range of the effective light-passing hole 1111 region is about 6mm, and the light-passing holes 1111 near the inner diameter are not used, and the distance between the light-passing holes 1111 at this point is slightly less than 0.25mm and is acceptable.

From the above relation, the relationship of Δ r to Δ θ can be determined.

The number of the light-passing holes 1111 of each Archimedes spiral 1110 is

Where 15mm is the difference between the inner and outer diameters of the spiral region 111, | | is a rounded symbol.

The number of Archimedes spirals 1110 is

Where the predetermined wide field area 112 is 20 °, the spiral area 111 is 340 °, and | is the integer symbol.

The jth light-passing hole 1111 of the ith Archimedes spiral is denoted by r (i, j).

Where r represents a polar coordinate, x represents an abscissa, and y represents an ordinate.

Here, substituting the calculation with γ = 30 ° as an example can obtain the following parameters:

1）

2）

3）

4）P=12，Q=2521

in some examples, the areas of the spiral region 111 other than the light passing holes 1111 may all be set to be opaque.

In some examples, the porous plate 10 may be fabricated by plating a light-shielding film (light-shielding plating layer) on the spiral region 111 on the light-transmissive base plate, and then by a photolithography process to form the usable porous plate 10. In other examples, the porous plate 10 may be made of an opaque material, for example, an opaque metal sheet or a non-metal sheet may be used to process the light passing holes 1111 shown in fig. 4 by laser drilling or other drilling methods to form the spiral regions 111. From this, can make the regional opaque outside logical unthreaded hole 1111 in the spiral region 111 through the shading cladding material, and then, can filter the reverberation outside the focal plane through the shading cladding material to realize the chromatography ability of confocal.

In some examples, the imaging module 4 may be configured to receive the reflected light beam L1' reflected by the spectroscopic module 3 from the object 6 for imaging, and the porous plate 10 may be rotated for at least one unit period to image the imaging module 4 for the first time, the porous plate 10 may be rotated for at least two unit periods to image the imaging module 4 again, and the periods of the multiple rotations of the porous plate 10 back and forth may be kept different.

In some examples, the image processing module 5 may be configured to receive at least two images imaged by the imaging module 4 and may fuse the at least two images of different exposure ranges into one high dynamic range image.

In the present disclosure, a first complete scan of a region to be measured of an object 6 for a first exposure time can be performed by rotating the porous plate 10 for at least one unit cycle while forming a first image in the imaging module 4, a second complete scan of a second exposure time different from the first exposure time can be performed on the region to be measured of the object 6 by continuing to rotate the porous plate 10 for at least two unit cycles while forming a second image in the imaging module 4, and then, two images of different exposure ranges can be fused into one image of a high dynamic range by the image processing module 5. Therefore, an image with a high dynamic range can be conveniently processed and obtained through the measuring system.

In some examples, the at least one unit period may be one, two, three, \8230;, nine, ten unit periods, etc. In some examples, the at least two unit periods may be two, three, four, \8230;, ten, eleven unit periods, and so on. Meanwhile, it can be ensured that the periods of the multiple rotations of the porous plate 10 back and forth are kept different, whereby the difference between the first exposure time and the second exposure time can be ensured. Similarly, when the imaging is performed for the third, fourth, fifth, 8230and 8230, the rotation periods of the porous plate 10 are different in each subsequent imaging, thereby ensuring different exposure times.

In some examples, the test object 6 may be referred to as a sample. The sample can be a semiconductor, a 3C electronic glass screen, a micro-nano material, an automobile part, an MEMS device or other ultra-precise devices. In some examples, the sample may be a device for application in the fields of aerospace and the like. In other examples, the sample may be a tissue or cell section of a biological field.

Fig. 8 is a flowchart illustrating one example of an optical measurement system-based imaging method according to an embodiment of the present disclosure. Fig. 9 is a flowchart illustrating another example of an optical measurement system-based imaging method according to an embodiment of the present disclosure.

Referring to fig. 8 and 9, the present disclosure also provides an imaging method based on an optical measurement system, which may be an imaging method based on the above-described porous plate 10 and confocal measurement system. In the present disclosure, the imaging method based on the optical measurement system may also be referred to as an imaging method based on an optical three-dimensional measurement system, an imaging method based on a confocal measurement system or an imaging method based on a confocal measurement system, or simply referred to as an imaging method.

In the present embodiment, the imaging method may include a preparation process of step S100, a disposition process of step S200, an imaging process of step S300, and an image processing process of step S400.

In some examples, the preparation process of step S100 may include step S110; the preparation process of step S200 may include step S210; the preparation process of step S300 may include step S310; the preparation process of step S400 may include step S410.

In step S110, the illumination module 2, the spectroscopy module 3, the scanning module 1, the imaging module 4, the image processing module 5, and the driving device to which the multi-well plate 10 is connected, and the like may be prepared.

In step S210, the illumination module 2 may be turned on for emitting the illumination light beam L1; the light splitting module 3 may be disposed between the illumination module 2 and the scanning module 1 and configured to receive the reflected light beam L1 'from the scanning module 1 and reflect the reflected light beam L1' to the imaging module 4; the multi-hole plate 10 may be disposed along the propagation direction of the illumination light beam L1, and the scanning module 1 may be configured to receive the illumination light beam L1 transmitted through the light splitting module 3 and emit the illumination light beam L1 to the object 6 and receive the reflected light beam L1 'from the object 6 and emit the reflected light beam L1' to the light splitting module 3; the imaging module 4 may be configured to receive the reflected light beam L1' reflected via the spectroscopic module 3 from the object 6 to be measured for imaging.

In some examples, the image processing module 5 may be connected with the imaging module 4 for receiving images imaged by the imaging module 4.

In some examples, the multi-well plate 10 may include a mounting region 120 and a scanning region 110.

In some examples, the mounting region 120 may be located at the center O of the porous plate 10 and used to mount a driving means for driving the porous plate 10 to rotate.

In some examples, the scanning area 110 may be arranged around the mounting area 120. In some examples, the scanning region 110 may include a spiral region 111 having a number of archimedean spirals 1110, the groups of through-holes of the archimedean spirals 1110 being formed to be rotationally symmetric around the center O of the multi-well plate 10.

In some examples, the spiral region 111 may include a plurality of sets of clear hole arrays 1120 arranged periodically in a manner to surround the center O of the multi-well plate 10, and the spiral region 111 may include at least three sets of clear hole arrays 1120.

In step S310, the multi-hole plate 10 may be rotated by at least one unit period by driving the driving device and the imaging module 4 may be imaged for the first time, the driving device may be continuously driven to continuously rotate the multi-hole plate 10 by at least two unit periods and the imaging module 4 may be imaged again, the unit period may be an angle of the group of clear hole arrays 1120 around the center O of the multi-hole plate 10, and the periods of the multiple rotations of the multi-hole plate 10 before and after may be kept different.

In some examples, if each set of the clear aperture arrays 1120 surrounds the center O of the multi-hole plate 10 at an angle θ (i.e., the unit period is θ), the optical measurement system may select the spiral region 111 to rotate x in turn ₁ θ、x ₂ θ、……、x _m The time of theta is taken as the exposure time, and x is required to be satisfied ₁ θ+x ₂ θ+……+x _m θ≤360°，x ₁ ，x ₂ ，……，x _m Are respectively positive integers and are not equal to each other. The image processing module 5 may be configured to fuse m images with different exposure ranges into one high dynamic range image. Therefore, the object 6 can be completely scanned for m times with different exposure times within one rotation circle of the multi-hole plate 10, and the image processing module 5 can fuse m images with different exposure ranges into one image with a high dynamic range.

Referring again to fig. 6, in some examples, the angle of each set of clear aperture arrays 1120 around the center O of the multi-well plate 10 may be 30 °, and one unit period θ of rotation of the spiral region 111 in the optical measurement system may be 30 °. At this time, the spiral region 111 may have at least 10 sets of the clear aperture array 1120. In some examples, at this point, the spiral region 111 may have 11 sets of clear aperture arrays 1120, and the last set of clear aperture arrays 1120 may be the tolerance region 1112.

In some examples, the optical measurement system may select as the exposure time the time for which the spiral region 111 rotates by 30 °, 60 °, 90 °, 120 ° in sequence, that is, when the unit exposure time is t ₀ Then, the optical measuring system can select t ₀ 、2t ₀ 、3t ₀ 、4t ₀ As the exposure time.

In a second step, the optical measurement system may select the helical region 111 to rotate 60 ° to bring the imaging module 4 into a second image 420. This corresponds to two exposures of the region of the test object 6.

In a third step, the optical measurement system may select that the spiral region 111 is rotated by 90 ° to bring the imaging module 4 into a third image 430. This corresponds to three exposures of the region of the test object 6.

Thus, the optical measurement system can perform 4 complete scans of the object 6 to be measured with different exposure times within one rotation of the multi-well plate 10, and can perform sufficient exposure step by step for each region where the reflectance of the surface of the sample decreases by gradually increasing the exposure time step by step.

In some examples, the illumination modules 2 in the optical measurement system may also select t in sequence within one revolution ₀ 、3t ₀ 、5t ₀ 、7t ₀ As exposure time; in other examples, the illumination modules 2 in the optical measurement system may also sequentially select 2t in one rotation ₀ 、5t ₀ 、7t ₀ As the exposure time. And the selection of the exposure time is adaptively selected according to different samples, and the selection basis is only required to ensure that the exposure time is different every time.

It is understood that the reflectance of the surface is generally different in different regions of the surface of one sample, and the porous plate 10 of the above example can perform one exposure of a region having a strong reflectance (for example, by rotating the porous plate 10 by θ) and perform multiple exposures of a region having a weak reflectance (for example, by rotating the porous plate 10 by x) within one rotation (360 °) of the porous plate 10 _m Theta), and finally the image processing module 5 can fuse the obtained multiple images with different exposure ranges into a high dynamic range image.

However, the above examples are not exclusive, and reference may be made to the porous plate 10, which will not be described herein.

In step S410, the image processing module 5 may be configured to receive the at least two images imaged by the imaging module 4, and fuse the at least two images with different exposure ranges into one image with a high dynamic range.

A first complete scan of the region to be measured of the object to be measured 6 for a first exposure time can be performed by rotating the porous plate 10 for at least one unit cycle while forming a first image in the imaging module 4; by continuing to rotate the porous plate 10 for at least two unit periods, and keeping the periods of the porous plate 10 for multiple rotations before and after different, a second complete scan of the region to be measured of the object 6 can be performed for a second exposure time different from the first exposure time, while forming a second image in the imaging module 4; then, the image processing module 5 can fuse two images with different exposure ranges into a high dynamic range image. Therefore, an image with a high dynamic range can be conveniently obtained by the imaging method.

In step S310, the multi-hole plate 10 may be rotated to form the image of the imaging module 4 for the third, fourth, and fifth times, 8230 \8230;, respectively. Finally, in step S410, the image processing module 5 may fuse the above-mentioned multiple frames of images with different exposure ranges to obtain a high dynamic range image.

The embodiments of the optical measurement system in the imaging method based on the optical measurement system can be described with reference to the optical measurement system part, and are not described herein again.

According to the present disclosure, it is possible to provide an optical measurement system and an imaging method based on the optical measurement system, in which the multi-hole plate 10 is imaged multiple times in one rotation cycle according to the difference of the surface reflectivity of the object 6, and multiple images of different exposure ranges are subjected to multi-frame fusion to form one high dynamic range image.

While the present disclosure has been described in detail in connection with the drawings and examples, it should be understood that the above description is not intended to limit the disclosure in any way. Variations and changes may be made as necessary by those skilled in the art without departing from the true spirit and scope of the disclosure, which fall within the scope of the disclosure.

Claims

1. An optical measurement system is characterized by comprising an illumination module, a light splitting module, a scanning module, an imaging module and an image processing module; the illumination module is used for emitting an illumination light beam; the light splitting module is arranged between the illumination module and the scanning module and is configured to receive a reflected light beam from the scanning module and reflect the reflected light beam to the imaging module; the scanning module comprises a multi-hole plate and a driving device for driving the multi-hole plate to rotate, the multi-hole plate is arranged along the propagation direction of an illuminating light beam, the scanning module is configured to receive the illuminating light beam transmitted by the light splitting module, emit the illuminating light beam to an object to be detected, receive a reflected light beam from the object to be detected and emit the reflected light beam to the light splitting module, the multi-hole plate comprises a mounting area and a scanning area, the mounting area is positioned in the center of the multi-hole plate and is used for mounting a driving device for driving the multi-hole plate to rotate, the scanning area is arranged around the mounting area, the scanning area comprises a spiral area with a plurality of Archimedes spirals, light through hole groups forming the Archimedes spirals are distributed in rotational symmetry around the center of the multi-hole plate, the spiral area comprises a plurality of light through hole arrays which are periodically arranged in a mode of surrounding the center of the multi-hole plate, and the spiral area comprises at least three sets of the light through hole arrays; the imaging module is configured to receive a reflected light beam from the object to be tested and reflected by the light splitting module for imaging, the porous plate rotates for at least one unit period to make the imaging module image for the first time, the porous plate continues to rotate for at least two unit periods to make the imaging module image for the second time, the unit period is an angle of a group of the light through hole arrays around the center of the porous plate, and the periods of the multiple rotations of the porous plate back and forth are different; the image processing module is used for receiving the images imaged by the imaging module at least twice and fusing at least two images with different exposure ranges into an image with a high dynamic range.

2. The optical measurement system of claim 1,

the porous plate further comprises a peripheral region surrounding the scanning region, the scanning region further comprises a tolerance region and a wide field region for wide field imaging, and a plating layer region is arranged on the peripheral region corresponding to the wide field region.

3. The optical measurement system of claim 2,

the shape of the porous disc is circular, the shapes of the scanning area and the peripheral area are circular rings, and the shapes of the spiral area, the tolerance area, the wide field area and the coating area are fan-shaped rings.

4. The optical measurement system of claim 1,

the angle of each group of the light-transmitting hole arrays surrounding the center of the porous plate is theta, and the optical measurement system selects the spiral regions to rotate x in sequence ₁ θ、x ₂ θ、……、x _m Time of theta as exposure time, x ₁ θ+x ₂ θ+……+x _m θ≤360°，x ₁ ，x ₂ ，……，x _m Are respectively positive integers and are not equal to each other; the image processing module is used for fusing m images with different exposure ranges into a high dynamic range image.

5. The optical measurement system of claim 1,

the illumination module includes a light source for emitting an illumination beam and a first polarization unit for converting a polarization state of the illumination beam from natural light to linearly polarized light.

6. The optical measurement system of claim 1,

the scanning module further comprises a second polarizing unit and a microscope objective, and the illuminating light beam sequentially passes through the porous disc, the second polarizing unit and the microscope objective to reach the object to be detected and is reflected by the object to be detected to form a reflected light beam.

7. The optical measurement system of claim 1,

the imaging module comprises a sensing unit and a third polarization unit arranged between the sensing unit and the light splitting module, and the sensing unit is configured to receive a reflected light beam transmitted through the third polarization unit.

8. The optical measurement system of claim 1,

the radial distances of all the light through holes in the radial direction of the porous plate are equal, and the radial angle distances of all the light through holes in the circumferential direction of the porous plate are equal;

the polar coordinate expression of the light through hole on the spiral area is as follows:

wherein r is the distance from the center of the light through hole to the center of the porous plate, n is the nth light through hole on the single spiral, r ₁ The distance from the center of the porous disc to the center of the light through hole at the beginning of the single spiral, delta r is the value of increasing unit angle r of the spiral along the radial direction of the porous disc, and delta theta is the argument increment of the adjacent light through holes of the single spiral;

the distance d between the adjacent light through holes of the single spiral satisfies the formula:

and the distance between the adjacent light through holes of the single spiral is equal to the distance between the light through holes in the radial direction of the multi-hole disc.

9. The optical measurement system of claim 1,

the central axis and the preset direction of the porous plate are provided with a first preset included angle larger than 0 degree, and the preset direction is the direction perpendicular to the bearing platform bearing the object to be tested.

10. An imaging method based on an optical measurement system is characterized by comprising the following steps: a preparation step of preparing an illumination module, a spectroscopic module, a scanning module, an imaging module, and an image processing module; a configuration procedure of turning on the illumination module for emitting an illumination beam; disposing the spectroscopy module between the illumination module and the scanning module and configured to receive a reflected beam from the scanning module and reflect the reflected beam to the imaging module; arranging the multi-hole disc along the propagation direction of the illumination light beam, and configuring the scanning module to receive the illumination light beam transmitted through the light splitting module and emit the illumination light beam to an object to be measured and receive a reflected light beam from the object to be measured and emit the reflected light beam to the light splitting module; configuring the imaging module to receive a reflected light beam from the object to be measured reflected by the light splitting module for imaging; the multi-hole disc comprises a mounting area and a scanning area, the mounting area is positioned in the center of the multi-hole disc and is used for mounting a driving device for driving the multi-hole disc to rotate, the scanning area is arranged around the mounting area and comprises a spiral area with a plurality of Archimedes spiral, the groups of light through holes forming the Archimedes spiral are distributed in a rotational symmetry mode around the center of the multi-hole disc, the spiral area comprises a plurality of groups of light through hole arrays which are arranged periodically in a mode of surrounding the center of the multi-hole disc, and the spiral area comprises at least three groups of the light through hole arrays; an imaging step of rotating the porous plate for at least one unit period by driving the driving device and imaging the imaging module for the first time, and continuing to drive the driving device to rotate the porous plate for at least two unit periods by which the group of light transmission hole arrays surround the center of the porous plate and imaging the imaging module again, wherein the unit periods of the multiple rotations of the porous plate are different; and the image processing module is used for receiving the images imaged by the imaging module at least twice and fusing at least two images with different exposure ranges into an image with a high dynamic range.