TW202140995A - Apparatus for surface profile measurement - Google Patents

Abstract

The present disclosure generally relates to an apparatus (20) for measuring a surface profile of an object (30), the apparatus (20) comprising: a light source assembly (100) comprising a broadband light source (110); a confocal microscopy assembly (200) comprising: a beam splitter (210) for directing uniform light from the broadband light source (110) to the object (30); a pinhole device (220) comprising an array of pinholes (222), the pinhole device (220) configured for passing the uniform light from the beam splitter (210) through the pinholes (222) to the object (30); a set of incident optical elements (230) for directing the uniform light from the pinhole device (220) to the object (30) and causing chromatic aberration of the uniform light passing through the incident optical elements (230); and the pinhole device (220) configured for passing light reflected from the object (30) through the pinholes (222) to the beam splitter (210), the reflected light comprising spectral information of the surface profile based on the chromatic aberration; and an optical detection assembly (300) comprising: an optical detector (310) for receiving the reflected light from the beam splitter (210); and a set of detection optical elements (320) for directing the reflected light from the beam splitter (210) to the optical detector (310), wherein the surface profile of the object (30) is measurable based on spectral information of the reflected light received by the optical detector (310), the spectral information representing heights across the surface profile.

Description

Surface profile measurement system

This disclosure generally relates to surface profile measurement. More specifically, this disclosure describes various embodiments of the object surface profile measurement system.

The surface profile of an object is an important feature for inspecting the quality of many industrial objects. Especially in the semiconductor industry, measurement and inspection of the surface profile of semiconductor devices such as wafers or substrates are regarded as part of the quality control and quality assurance process. A traditional object surface profile measurement method is to use confocal microscope technology. Specifically, a confocal sensor is used to measure multiple points on the surface of the object to determine the relative height of these points on the surface. Then these little by little measurements are combined to estimate the surface profile of the object. However, it takes time to measure each individual point on the surface, making the measurement of the surface profile slow. These arbitrary points also cannot cover all the area of the surface, potentially excluding the relevant area of interest of the surface contour.

In order to solve or eliminate at least one of the above-mentioned problems and/or shortcomings, there is an urgent need to provide an improved object surface profile measurement system.

According to one aspect of the present disclosure, an object surface profile measurement system is provided. The system includes: a light source assembly, including a broadband light source; a confocal microscope assembly, including: a beam splitter for dividing uniform light from the broadband Guided to the object; a pinhole device comprising an array of pinholes, the pinhole device being configured to allow the uniform light from the beam splitter to pass through the pinholes to the object; a set of incident optical elements , Used to guide the uniform light from the pinhole device to the object, and cause the uniform light passing through the incident optical elements to cause chromatic aberration; and the pinhole device is configured to cause reflection from the object The light passes through the pinholes to the beam splitter, the reflected light includes the spectral information of the surface profile based on the chromatic aberration; and an optical detection component includes: an optical detector that receives the beam splitter The reflected light of the optical detector; and a set of detecting optical elements, which guide the reflected light from the beam splitter to the optical detector; wherein, according to the reflected light received by the optical detector The spectral information of can measure the surface profile of the object, and the spectral information represents the height across the surface profile.

An object surface profile measurement system according to the present disclosure is disclosed here. From the following detailed description of the non-limiting exemplary embodiments of the present disclosure and the accompanying drawings, various features, aspects, and advantages of the present disclosure will become more apparent.

For the sake of brevity and clarity, according to the drawings, the description of the embodiment of the present disclosure is about a measurement system for the surface profile of an object. Various aspects of the disclosure are described in conjunction with the embodiments provided herein, and it should be understood that they are not intended to limit the disclosure to these embodiments. On the contrary, the present disclosure intends to cover various variations, modifications, and equivalent means of the embodiments described herein, which are included in the scope of the present disclosure defined by the appended patent scope. Furthermore, the following detailed description states specific details to facilitate a thorough understanding of this disclosure. However, those with ordinary knowledge in the art, that is, those familiar with the art, will understand that the present disclosure can still be implemented without mentioning the specific details and/or some details of the combination of the various aspects of the specific embodiment. Some examples do not describe in detail known systems, methods, procedures, and components in order to avoid unnecessarily obscuring aspects of the disclosed embodiments.

In the embodiments of the present disclosure, the same, equal or similar elements or corresponding materials appearing in different drawings adopt the same element numbers or symbols.

References to “one embodiment/example”, “another embodiment/example”, “some embodiments/examples”, “some other embodiments/examples”, etc. mean that the described embodiments/examples may include one Specific features, structures, features, characteristics, elements, or limiting elements, but not every embodiment/example needs to include these specific features, structures, features, characteristics, elements, or limiting elements. Furthermore, repeated use of "in one embodiment/example" or "in another embodiment/example" does not necessarily refer to the same embodiment/example.

"Include", "include", "have" and similar terms do not exclude features/elements/steps other than those listed in the embodiments. Certain features/elements/steps defined in different embodiments do not mean that the combination of these features/elements/steps cannot be used in one embodiment.

As used herein, the term "a" refers to one or more than one. Unless otherwise specified, the use of "/" in diagrams or text represents "and/or". The term "group" is defined as a non-empty but finite set of elements. According to known mathematical definitions, it mathematically represents at least one cardinal number (for example, the definition of a group corresponds to a unit, a single state, or a single An element group, or a group of several elements. The definition of a specific value or a value range here is understood to include an approximate value or an approximate value range. The use of "first", "second", etc. is only for labeling purposes. It is not intended to add digital requirements to related terms.

Please refer to the first figure. In a representative or exemplary embodiment of the present disclosure, a system 20 is used to measure the surface profile of an object 30. The system 20 includes a light source assembly 100, a confocal microscope assembly 200, and an optical detection assembly 300. The system 20 further includes a platform for supporting the object 30 during the measurement. The platform can be configured to be displaceable, whereby, for example, the object 30 can be translated to measure different areas or the entire area of the surface profile.

The light source assembly 100 includes a broadband light source 110 configured to emit a broadband uniform light with a continuous wavelength range of a broad band. For example, the broadband uniform light is white light that covers the wavelength of the visible color spectrum and may include the wavelength of the infrared and/or ultraviolet spectrum.

The confocal microscope assembly 200 includes a set of incident optical elements 230, such as lenses and/or mirrors, for guiding the uniform light from the pinhole device 220 to the object 30 and causing chromatic aberration through the incident optical elements 230. aberration). In addition, the pinhole device 220 is configured to cause the reflected light from the object 30 to pass through the pinholes 222 to the beam splitter 210, and the reflected light includes the spectral information of the surface profile based on the color difference. More specifically, the pinholes 222 are configured to only allow light focused on the object 30 and reflected from the object 30 to pass through the beam splitter 210. The pinhole device 220 blocks all reflected light that is not focused on the object 30 so that the reflected light does not enter the pinholes 222.

The optical detection component 300 includes an optical detector 310 for receiving the reflected light from the beam splitter 220. The optical detection assembly 300 includes a set of detection optical elements 320 which guide the reflected light from the beam splitter 210 to the optical detector 310. The surface profile of the object 30 is measured according to the spectral information of the reflected light received by the optical detector 310, and the spectral information represents the height across the surface profile. For example, the spectral information includes information about the wavelength of the reflected light focused on the object 30 and reflected to the pinholes 222, where the wavelength can be used to determine the height change across the surface profile.

In various embodiments of the present disclosure, the second figure shows a method 400 for measuring the surface profile of the object 30, wherein the method 400 is executed through the system 20. The method 400 includes step 402 of guiding the uniform light from the broadband light source 110 to the object 30 through the beam splitter 210. The method 400 includes a step 404 of allowing the uniform light from the beam splitter 210 to pass through the array of pinholes 222 of the pinhole device 220 to the object 30. The method 400 includes the step 406 of guiding the uniform light from the pinhole device 220 to the object 30 through the set of incident optical elements 230, and generating chromatic aberration when the uniform light passes through the incident optical elements 230 ( chromatic aberration). The method 400 includes step 408, allowing the reflected light of the object 30 to pass through the array of pinholes 222 to the beam splitter 210, the reflected light including the spectral information of the surface profile based on the color difference. The method 400 includes step 410 of guiding the reflected light from the beam splitter 210 to the optical detector 310 through the group of detecting optical elements 320. The method 400 includes step 412 of transmitting the reflected light received from the beam splitter 210 through the optical detector 310. The method 400 includes step 414 of measuring the surface profile of the object 30 according to the spectral information of the reflected light received by the optical detector 310, the spectral information representing the height across the surface profile.

As mentioned above, the incident optical elements 230 cause the chromatic aberration of the uniform light propagating from the pinhole device 220 to the object 30, and the reflected light from the object 30 contains spectral information based on the chromatic aberration, such as wavelength . More specifically, the group of incident optical elements 230 causes axial or longitudinal chromatic aberration of the light, which causes the light of different wavelengths from the incident optical elements 230 to be focused to the object 30 along different focal distances. Due to the chromatic aberration, the rays of different wavelengths will be focused on the position of the object 30 at different heights or depths across the surface contour with respect to a reference plane along the surface contour. For example, red light (having a wavelength of approximately 620nm to 720nm) is focused at a lower height, blue light (having a wavelength of approximately 460nm to 500nm) is focused at a higher altitude, and green light (having a wavelength of approximately 500nm to 570nm) is focused An intermediate height between the two, where these heights are relative to the reference plane.

The wavelength clearly focused on the surface profile of the object 30 is reflected from the object 30, and the reflected light in turn becomes incident light that reaches the surface profile along the same propagation path and focuses on the surface profile. The wavelengths of the reflected light focused on the object 30 pass through the pinhole device 220 to the beam splitter 210, while the wavelengths of the reflected light not focused on the object 30 may be reflected back but will not be aligned with the pinholes 222, and cannot pass through the pinholes 222. In other words, the pinhole device 220 will block all the reflected light that is not focused on the object 30. Therefore, only the wavelength of the reflected light reflected from the object 30 passes through the pinholes 222 to the beam splitter 210. The reflected light is then imaged on a conjugate plane of the pinhole device 210 and is received by the optical detector 310. Only the wavelengths of the reflected light focused on different heights across the surface profile are reflected from the object 30 and received by the optical detector 310. These wavelengths represent the heights, and the surface profile can be measured in three dimensions based on these wavelengths . The color spectrum image of the surface profile can accurately measure the three-dimensional height profile across the surface profile without vertically scanning or moving any parts of the system 20.

Since the pinhole device 220 blocks most of the light incident on the surface of the pinhole device 220, that is, the surrounding area of the pinholes 222, the pinhole device 220 may include appropriate optical elements to minimize or prevent light reflection . For example, light incident on the top surface of the pinhole device 220 can be reflected back to the beam splitter 210 and merged with the reflected light from the object 30, potentially affecting the accuracy of the surface profile measurement. These optical elements can promote the focusing of light into the pinholes 222, thereby improving the spectral imaging and the measurement of the surface profile.

As shown in the third figure, the pinhole device 220 may include one or more arrays of microlenses 224 to match the array of pinholes 222. For example, the pinhole device 220 includes a first array of microlenses 224 arranged on top of the pinholes 222, so that each pinhole 222 matches a microlens 224 of the first array, and the first array of microlenses 224 The iso-microlens 224 is configured to focus the light from the beam splitter 220 into the individual pinholes 222. The pinhole device 220 can optionally include a second array of microlenses 224 disposed under the pinholes 222, so that each of the pinholes 222 matches a second array of microlenses 224, and the second array of microlenses 224 The microlenses 224 are configured to focus the reflected light from the object 30 into the individual pinholes 222. The arrays of pinholes 222 and microlenses 224 can be formed separately and combined together, or they can be integrated together into a unit.

Each of the pinholes 222 is paired with at least one of the microlenses 224, and they cooperate to focus the light into the center of the individual pinholes 222. The microlenses 224 are specifically matched with the pinholes 222 to align their center focal points, so as to focus the light irradiated by a person on the microlenses 224 into the pinholes 222. In this way, more light energy is collected on one or both sides of the pinhole device 220, and the amount of light guided into each pinhole 222 is increased, thereby improving the light efficiency, because the light efficiency of the traditional confocal microscope is very high. Low. The curved surfaces of the microlenses 224 can disperse and remove unnecessary light incident on their surfaces, thereby improving the quality of light passing through the pinholes 222.

As shown in the third figure, the microlenses 224 are arranged together so that they are in contact with each other or there are some gaps between them. Since the diameter of the pinholes 222 is smaller than the diameter of the microlenses 224, there will be gaps between the pinholes 222. As shown in the fourth figure, these gaps are represented by the pitches P1 and P2 in two vertical directions, for example, along the X axis and the Y axis, respectively. By projecting the pinholes 222 onto the object 30, the pinholes 222 correspond to a plurality of independent points of the surface contour of the object 30, and the gaps or spacings P1 and P2 between the pinholes 222 correspond to The interval between these independent points.

One advantage of the pinholes 222 is that the heights of the independent points of the surface profile can be measured at the same time. The independent points are allocated to at least one sampling area, or in some examples, to substantially the entire area of the surface profile, so that the system 20 can perform rapid sampling measurement of the sampling area. It should be noted that the number of the independent points depends on the number of the pinholes 222, so that a larger number of the pinholes 222 can increase the sampling area to be measured and/or improve the measurement resolution. The high-speed sampling measurement of the independent points of the sampling area is beneficial to various practical applications, especially when it is necessary to quickly inspect a batch of the objects 30.

Since the pinhole device 220 remains stationary during sampling and measurement, the gap between the independent points will not be imaged and measured. To solve this situation, in some embodiments, the confocal microscope assembly 200 may include a driving mechanism 240 for moving the pinhole device 220 planarly. As shown in FIG. 5, the driving mechanism 240 can be configured to move the pinhole device 220 along the X-axis and/or Y-axis plane. Alternatively, the driving mechanism 240 may be configured to rotate the pinhole device 220 planarly around the Z axis, so that the pinhole device 220 is maintained on the XY plane during the rotation. For example, the driving mechanism 240 includes drivers such as motors and piezoelectric drivers.

When the pinhole device 220 moves along the XY plane, the pinholes 222 and the corresponding points on the surface contour will move across the surface contour, so that light can reach and scan a continuous surface area and approximately Draw the contour of the entire surface. Roughly all areas of the surface contour can be scanned and measured seamlessly, thereby eliminating the risk of the area of interest of the surface contour being excluded. Therefore, a more detailed measurement of the surface profile can be obtained, so that a higher quality inspection of the object 30 is provided.

In the embodiment shown in the first figure, the system 20 includes the light source assembly 100, the confocal microscope assembly 200, and the optical detection assembly 300 as described above. The light source assembly 100 includes the broadband light source 110, which is configured to emit broadband uniform light, such as white light. As shown in FIG. 6, the broadband light source 110 includes a group of lights 112. The lamp 112 may be an incandescent lamp or a broadband white light emitting diode. For example, the incandescent lamp is a halogen lamp, such as a tungsten halogen lamp. The light 112 may be of low power, such as 50 watts, to reduce wasted heat generated by using the system 20. The low-power light 112 can eliminate the fan required for cooling equipment, thereby reducing mechanical vibration and power consumption. However, the light source assembly 100 may include a small heat sink to remove any heat generated by the broadband light source 110.

The broadband light source 110 includes an optical aperture 114 for guiding the uniform light emitted from the lamp 112 to leave the broadband light source 110. The optical aperture 114 may be circular and configured to control the diameter of the beam emitted from the broadband light source 110 to the confocal microscope assembly 200. The broadband light source 110 may include an optical integrating shperer 116 configured to integrate light energy from the lights 112. The optical integrating sphere 116, known as the Ulbricht sphere, is an optical component with hollow spheres and an internal reflective coating for uniformly scattering light and reducing light loss. As shown in Figure 6, the lights 112 are arranged around the optical integrating sphere 116, so that the light from the lights 112 is guided into the hollow sphere and reflected toward the interior of the optical integrating sphere 116 Coating so that the internal reflective coating reflects the lights to the optical aperture 114.

The broadband light source 110 may include an optical bandpass filter, which is configured to filter out light outside a predetermined wavelength range. The optical band pass filter is disposed between the lights 112 and the optical integrating sphere 116, such as the optical aperture 114. For example, the optical bandpass filter includes a dichroic filter or a dielectric mirror. The predetermined wavelength range may correspond to the visible light color spectrum, or the region from red light to blue light, and the optical band pass filter allows all visible light to pass through and leave the optical aperture 114. The unnecessary light outside the visible color spectrum, such as infrared light and ultraviolet light, is blocked by the optical band pass filter. It should be noted that infrared light is hotter than visible light. By blocking the infrared light, less heat will be transferred from the optical aperture 114, thereby eliminating thermal damage to the confocal microscope assembly 200.

The uniform light from the broadband light source 110 can propagate through the optical aperture 114 and directly to the confocal microscope assembly 200. Alternatively, the light source assembly 110 may include a Köhler illumination device 120 having one or more lenses disposed between the broadband light source 110 and the confocal microscope assembly 200. The Kohler illumination system 120 provides parallel and uniform light to the confocal microscope assembly 200.

The confocal microscope assembly 200 includes the beam splitter 210, the pinhole device 220, and the set of incident optical elements 230 as described above. The incident optical element 230 includes an objective lens 232 for focusing light on the object 30, and a tube lens 234 for focusing the reflected light from the object 30 on the pinhole device 220 . The incident optical element 230 further includes a chromatic aberration lens 236, which is disposed between the objective lens 232 and the tube lens 234 to cause chromatic aberration of light. The chromatic aberration lens 236 is designed to have specific chromatic aberration characteristics and good linearity. Depending on the desired measurement range and resolution, different chromatic aberration lenses 236 can be used. Alternatively, the chromatic aberration lens 236 and the objective lens 232 can be integrated into a single lens element. With chromatic aberration, light of different wavelengths can be clearly separated, and the different heights of the surface profile can be clearly distinguished, so that the surface profile can be three-dimensionally imaged and measured.

The optical detecting component 300 includes the optical detector 310 and the set of detecting optical elements 320 as described above. The detecting optical element 320 may include an imaging lens 322 for guiding the reflected light from the beam splitter 210 to the optical detector 310. The optical detector 310 may include a color camera 312, which is an image sensor with red-green-blue (RGB) colors, such as a CCD or CMOS image sensor. The imaging lens 322 is configured to focus the reflected light containing the spectral information on the image sensors of the color camera 312, thereby allowing the reflection of the reflected light from the surface profile of the object 30 The spectral information is imaged on the color camera.

The working spectral range of the color camera 312 can cover the visible color spectrum and optionally the infrared spectrum and/or the ultraviolet spectrum. For example, the working spectral range of the color camera 312 may be approximately 380 nm to 1000 nm. An infrared filter can be added to the color camera 312 to exclude infrared and/or near infrared. As described above, according to the accurate spectral information and wavelength of the reflected light, different heights or depths across the surface profile are imaged in different colors, and the spectral image captured by the surface profile can accurately measure the three-dimensional surface Contour, where the different heights across the surface contour are represented by different spectral colors in the spectral image. The seventh figure shows an example of an RGB spectral image 40, which includes the corrected RGB curve of the object 30 captured by the color camera 312. The system 20 can be integrated or coupled with an image processing module to generate the surface profile of the object 30 according to the spectral image 40. More specifically, the image processing module calculates the surface profile of the object 30 based on the spectral image 40 received by the optical detector 310, where the color or wavelength of each point (corresponding to the pinholes 222) represents the surface The height of the contour at that point. The collection of all points represents the height change across the entire surface profile.

In one embodiment, the light source assembly 100, the confocal microscope assembly 200, and the optical detection assembly 300 are arranged as shown in the first figure. When the system 20 is used, the uniform light from the light source assembly 100 passes through the beam splitter 210 to the object 30, reflects from the object 30 back to the beam splitter 210, and the beam splitter 210 reflects the light to the object 30. Optical detection component 300. Since the beam splitter 210 is configured to transmit and reflect light (preferably in equal proportions), the system 20 can have other configurations. As in the embodiment shown in Figure 8, when the system 20 is used, the light from the light source assembly 100 reaches the beam splitter 210, is reflected to the object 30, and is reflected from the object 30 back to the beam splitter 210, And it passes through the beam splitter 210 to the optical detection assembly 300.

In summary, in the embodiments shown in Figures 1 and 8, the system 20 includes the light source assembly 100, the confocal microscope assembly 200, and the optical detection assembly 300, which are configured to measure the object 30 The surface profile. The light source assembly 100 includes the broadband light source 110 and the Kohler lighting device 120. The confocal microscope assembly 200 includes the beam splitter 210 and the pinhole device 220 with the pinhole 222 arrays, and the microlenses 224 with one or more arrays of the pinhole 222 arrays. The confocal microscope assembly 200 further includes the group of incident optical elements 230 and the driving mechanism 240 for moving the pinhole device 220 along the X-axis and Y-axis in a plane. The incident optical elements 230 include the objective lens 232, the tube lens 234, and the chromatic aberration lens 236. The optical detection component 300 includes the optical detector 310 with the color camera, and further includes the group of detection optical elements 320 with the imaging lens 322 that focuses the reflected light on the color camera 312.

In the embodiment shown in FIG. 9, the system 20 is substantially similar to the embodiment in FIG. 1 except for the optical detection component 300. The above description of the various aspects of the embodiment in the first figure can be equally or similarly applied to the embodiment in the ninth figure, and vice versa. The optical detector 310 includes a hyperspectral camera 314, and the optical detection assembly 300 can be used as a one-shot hyperspectral imaging assembly 302. The hyperspectral camera 314 can more finely capture the spectral information of the reflected light and obtain the hyperspectral information of the surface profile. Furthermore, the hyperspectral camera 314 is a one shot or single shot hyperspectral camera, which captures only one image to obtain the hyperspectral information of the surface profile. The hyperspectral camera 314 can capture the hyperspectral information in full color or monochrome. For example, the hyperspectral camera 314 is a high-resolution full-color or monochromatic camera.

Normal spectral imaging or multispectral imaging (normal spectral imaging or multispectral imaging) usually captures and processes images with three broad band wavelengths corresponding to RGB colors. This is because the human eye can see most of them in these three broad bands. The colors of visible light. Hyperspectral imaging can capture and process images from infrared spectrum to ultraviolet spectrum or even electromagnetic spectrum including X-ray spectrum. Compared with general RGB bands, hyperspectral imaging divides the electromagnetic waves into more bands and covers a wide wavelength range with fine wavelength resolution. Regular spectral imaging measures separated RGB spectral bands, but conversely, hyperspectral imaging measures multiple continuous spectral bands. The hyperspectral camera 314 can capture and process images of the object 30 in a very large number of fine wavelengths, and the hyperspectral information can be split into a very large number of colors corresponding to these fine wavelengths.

The single-shot hyperspectral imaging component 302 includes an aperture device 330, and the reflected light from the beam splitter 210 passes through the aperture device 330 to the hyperspectral camera 314. The aperture device 330 includes at least one aperture or a hole to allow light to pass through. The single-shot hyperspectral imaging component 302 includes a wavelength differentiation device 340, which is disposed between the aperture device 330 and the hyperspectral camera 314 to separate the reflected light so as to pass through the Spectral information such as wavelength distinguishes the reflected light more clearly. The wavelength division device 340 may be a grating that diffracts the reflected light or an optical beam that scatters the reflected light.

In the single-shot hyperspectral imaging component 300 as shown in FIG. 9, the group of detecting optical elements 320 includes the imaging lens 322, which is disposed in front of the hyperspectral camera 314 and behind the grating 340. The imaging lens 322 is configured to focus the reflected light from the grating 340 on the image sensor of the hyperspectral camera 314, so as to image the spectral information of the reflected light from the surface profile of the object 30 In the hyperspectral camera 314. The detecting optical element 320 further includes a collimator 324 disposed between the aperture device 330 and the grating 340. The collimator 324 is a device, such as a curved lens or a mirror, which narrows the beam and aligns it to a specific direction. It should be noted that the collimator 324 aligns the reflected light from the aperture device 330 to the grating 340, and the grating 340 more clearly distinguishes light into its continuous spectrum of wavelengths. The detecting optical element 320 may further include a relay lens 326 disposed between the beam splitter 210 and the aperture device 330. The relay lens 326 is configured to project the surface profile image formed on the pinhole device 220 on the aperture device 330 via the beam splitter 210.

According to the spectral information of the reflected light, the imaging lens 322 projects the diffracted wavelength of the reflected light on the hyperspectral camera 314 at separated wavelengths. Due to the effect of the microlenses 224 increasing the amount of light guided to the pinholes 222, the image sensitivity is improved and the full spectrum of each point of the surface contour of the object 30 is imaged by the hyperspectral camera 314. The tenth figure illustrates the hyperspectral image 50 of the object 30 captured by the single-shot hyperspectral imaging component 302. The system 20 can be integrated or coupled with an image processing module to generate the surface profile of the object 30 according to the hyperspectral image 50. Since it is a full-scale hyperspectrum of the 3D surface profile, in addition to the surface profile, the sub-surface profile and multilayer thickness of the surface of the object 30 can be measured and inspected finely. Hyperspectral imaging can therefore measure the comprehensive spectrum of the surface profile in high resolution and detail, and the system 20 can have a wide range of applications in various fields and is not limited to online inspection and semiconductor industry, electronics industry, precision engineering, optics, Biomedical agriculture, and food industry.

In the embodiment shown in FIG. 9, the aperture device 330 includes an array of pinholes 332 similar to the pinholes 222 of the pinhole device 220. The aperture device 330 may further include an array of microlenses 334 with an array of the pinholes 332. Specifically, the aperture device 330 includes the array of microlenses 334 arranged in front of the pinholes 332, that is, between the beam splitter 210 and the pinholes 332, for example, each pinhole 332 is matched with one The micro lens 334. The pinhole 332 array and the microlens 334 array can be formed separately and coupled together, or they can be integrated into a unit. Each of the pinholes 332 is paired with a microlens 334, and they cooperate to focus the light on the center of the individual pinholes 332.

In summary, in the embodiment shown in FIG. 9, the system 20 includes the light source assembly 100, the confocal microscope assembly 200, and the optical detection assembly 300. The optical detection component 300 is a single-shot hyperspectral imaging component 302 configured to measure the surface profile of the object 30 and the subsurface profile including the thickness of the multilayer film. The light source assembly 100 includes the broadband light source 110 and the Kohler lighting device 120. The confocal microscope assembly 200 includes the beam splitter 210, the pinhole device 220 having the pinhole 222 arrays, and the microlenses 224 matching one or more arrays of the pinhole 222 arrays. The confocal microscope assembly 200 further includes the incident optical elements 230 and the driving mechanism 240 for moving the pinhole device 220 planarly along the X axis and the Y axis. However, the system 20 can exclude or stop the driving mechanism 240 to perform rapid sampling and measurement of the object 30. The incident optical element 230 includes the objective lens 232, the tube lens 234, and the chromatic aberration lens 236. The single-shot hyperspectral imaging component 302 includes the optical detector 310 with the hyperspectral camera 314, the aperture device 330 with an array of microlenses 234 with an array of the pinholes 332, and the wavelength separation device (wavelength differentiation device). The single-shot hyperspectral imaging component 302 further includes the group of detecting optical elements 320 having the relay lens 326, the collimator 324, and the imaging lens 322.

In the embodiments of the first and ninth figures, the system 20 is configured to scan the 2D area of the surface profile of the object 30. Specifically, the array of the pinholes 222 of the pinhole device 220 is arranged across a 2D plane. In the embodiment of FIG. 11, the system 20 is configured to perform a linear scan of the surface profile of the object 30. The aspects of the above-mentioned first figure and the ninth figure can be similarly or similarly applied to the embodiment of the eleventh figure, and vice versa. In the embodiment of FIG. 11, the pinholes 222 and similarly the microlenses 224 can be arranged in a single row (one-dimensional arrangement) to replace the pinholes 222 of the two-dimensional array. Similarly for the pinhole device 330, the pinholes 332 and similarly the microlenses 334 can be arranged in a single row (one-dimensional arrangement) instead of the pinholes 332 of the two-dimensional array. Alternatively, the single row of pinholes 332 can be replaced by the one-dimensional slit aperture 336 shown in FIG. 11.

Alternatively, the optical aperture 114 of the broadband light source 110 is a linear aperture to correspond to a single row of pinholes 222/332. The Kohler illuminator 120 can also be replaced by a tube lens 122 that focuses the broadband light beam into a linear light beam. The driving mechanism 240 for moving the pinhole device 220 in a plane can be configured to move the pinhole device 220 in a direction parallel to the single row of pinholes 222 to cover the gap or spacing between the pinholes 222. For example, the pinholes 222 are spread out and arranged along the X-axis across the surface contour, and the driving mechanism 240 is configured to move the pinhole device 220 along the X-axis. The driving mechanism 240 cooperates with the displaceable platform supporting the object 30 to measure the entire surface profile of the object 30. For example, the driving mechanism 240 moves the pinholes 222 along the X axis and the platform moves the object 30 along the Y axis. When the linear beam moves across the surface contour, the optical detector 310 (such as the color camera 312 or the hyperspectral camera 314) captures one column of spectra at a time. The twelfth figure illustrates the hyperspectral image 60 in the form of a continuous spectrum of the object 30 captured by the hyperspectral camera 314.

In summary, in the embodiment of FIG. 11, the system 20 is configured to linearly scan the object 30 and includes the light source assembly 100, the confocal microscope assembly 200, and the optical detection assembly 300, and the optical The detection component 300 is the single-shot hyperspectral imaging component 200. The light source assembly 100 includes the broadband light source 110 and the tube lens 122. The tube lens 122 focuses the uniform light from the broadband light source 110 into a linear beam to scan the object 30 linearly. The confocal microscope assembly 200 includes the beam splitter 210, the pinhole device 220 with a single row of pinholes 222 array for linear scanning, and one or more arrays of microlenses 234 with the single row of pinholes 222 array . The confocal microscope assembly 200 further includes the set of incident optical elements 230 and the driving device 240. The driving device 240 is used to move the pinhole device 220 in a plane parallel to the single row of pinholes 222, for example along the X axis. The incident optical element 230 includes the objective lens 232, the tube lens 234, and the chromatic aberration lens 236. The single-shot hyperspectral imaging component 302 includes the optical detector 310 with the hyperspectral camera 314, the aperture device 330 with the slit aperture 336 for linear scanning, and the wavelength separation device 340. Alternatively, the aperture device 330 includes a single row of pinholes 332 for linear scanning and a single row of microlenses 334 matched with the single row of pinholes 332. The single-shot hyperspectral imaging component 302 further includes the group of detecting optical elements 320, and the group of detecting optical elements 320 has a relay lens 326, a collimator 324, and an imaging lens 322.

In the embodiment shown in FIG. 13, except for the pinhole device 220, the system 20 is substantially similar to the embodiment shown in FIG. 9. However, the aspects of the embodiment shown in the first figure, the ninth figure and the eleventh figure above can be equally or similarly applied to the embodiment of the figure thirteenth, and vice versa. In the embodiment of FIG. 13, the pinhole device 220 is a Nipkow disk 226. The Nipkov disk 226 is a scanning disk with pinholes 222 that are equidistant and round or square. The driving mechanism 240 is configured to rotate the Nipkov disc 226 planarly around the Z axis. Preferably, the pinholes 222 are positioned from an outer radial point of the Nipkov disc 226 toward the center thereof to form a single-turn spiral, which facilitates when the driving mechanism 240 rotates the Nipkov disc 226. The pinholes 222 chase the circular pattern trajectory when the Cove disk 226 is. As mentioned above, when the Nipkov disk 226 rotates, the pinholes 222 and the corresponding points on the surface contour of the object 30 are moved to pass through the surface contour, and a continuous surface area of the surface contour is changed. Scan and measure.

In the embodiment of FIG. 14, the Nipkov disc 226 further includes a first array of microlenses 224, which are arranged on top of the pinholes 222. As shown in Figure 15, the Nipkov disk 226 may further include a second array of microlenses 224, which are arranged below the pinholes 222, that is, the array of pinholes 222 is located on the first Between an array and the microlenses 224 of the second array. Each pinhole 222 is matched with at least one microlens 224, and the microlens 224 is configured to focus light into the individual pinholes 222.

In summary, in the embodiments shown in FIGS. 13 to 15, the system 20 includes the light source assembly 100, the confocal microscope assembly 200, and the optical detection assembly 300. The optical detection component 300 is the single-shot hyperspectral imaging component 302. The light source assembly 100 includes the broadband light source 110 and the Kohler lighting system 120. The confocal microscope assembly 200 includes the beam splitter 210 and the pinhole device 220. The pinhole device 220 is the Nipkov disc 226 with an array of pinholes 222. The Nipkov disk 226 may further include one or more arrays of microlenses 224 matching the pinhole 222 arrays. The confocal microscope assembly 200 further includes the group of incident optical elements 230 and the driving mechanism 240 that rotates the pinhole device 220 along the Z axis. The incident optical element 230 includes the objective lens 232, the tube lens 234, and the chromatic aberration lens 236. The single-shot hyperspectral imaging component 302 includes the optical detector 310 with the hyperspectral camera 314, the aperture device 330 with the array of pinholes 332, and an array microlens 334 with the array of pinholes 332 , And the wavelength separation device 340. The single-shot hyperspectral imaging component 302 further includes the group of detecting optical components 320, and the group of detecting optical components 320 has the relay lens 326, the collimator 324, and the imaging lens 322.

In the embodiment of FIG. 16, the system 20 includes the light source assembly 100, the confocal microscope assembly 200, and the optical detection assembly 300 as described above. The light source assembly 100 includes the broadband light source 220 and the Kohler lighting device 120. Although it can be understood that the optical detection component 300 may be the single-shot hyperspectral imaging component 302, the optical detection component 300 includes the color camera 312 and the imaging lens 322.

The confocal microscope assembly 200 includes the beam splitter 210, the pinhole device 220 in the form of a Nipkov disc 226, and the driving mechanism 240 for rotating the Nipkov disc 226. The confocal microscope assembly 200 further includes the barrel lens 234, the chromatic aberration lens 236, and the objective lens 232 for cooperating to focus the light on the object 30 chromatic aberration. The object 30 is supported on a movable platform 32. For example, the platform 32 is coupled or integrated with drivers such as motors and piezoelectric drivers. The drivers can move the platform 32 along at least one of the XYZ axes and/or rotate the platform 32 around at least one of the XYZ axes.

In the embodiment shown in FIG. 16, the group of incident optical elements 230 includes a first objective lens 232 and a second objective lens 238. The confocal microscope assembly 200 further includes a conversion device or stage 250 supporting the first and second objective lenses 232 and 238. The conversion device 250 may include a driver such as a motor and a piezoelectric driver, and may be operated between the first and second objective lenses 232 and 238. For example, the first objective lens 232 has a higher magnification and the second objective lens 238 has a lower magnification. In addition, the group of incident optical elements 230 may include multiple objective lenses, and these objective lenses can be switched with each other through the conversion device 250, wherein the objective lenses can have different magnifications, which facilitates the selection of measurement performance.

Although the three-dimensional surface profile measurement system 20 can mainly be used for online high-speed measurement and inspection, it can also be used as an independent measurement system for sampling measurement. The sixteenth figure illustrates this independent measurement system 20.

As mentioned above, the system 20 includes the broadband light source 110, the lighting device 120, and the beam splitter 210. The beam splitter 210 guides uniform illumination light to the surface of the Nipkov disk 226. Some light is blocked by the Nipkov disc 226, and some light passes through the pinholes 222 of the Nipkov disc 226. The light from the pinholes 222 passes through the barrel lens 234, the chromatic aberration lens 236, and finally passes through the objective lens 232 to focus on the surface of the object 30 placed on the mechanically movable platform 32.

An observation device 500 is arranged between the objective lens 232 and the barrel lens 234 to observe and select the area of the surface contour to be inspected. The observation device 500 includes a first beam splitter 510, a second beam splitter 520, an eyepiece 530, an imaging lens 540, and a camera 550. The surface profile of the object 30 is imaged through the objective lens 232 and reflected by the first beam splitter 510 and the second beam splitter 520. The image can be formed by the imaging lens 540 and the camera 550. The image of the object 30 can also be directly observed through the eyepiece 530 with naked eyes. The observation device 500 can be moved in for observation and moved out to perform three-dimensional surface profile measurement.

As in the various embodiments described above, the system 20 and the method 400 measure the surface contour of the object 30 by capturing a single image of the surface contour and using spectral analysis to generate the surface contour of the object 30. The light source assembly 100 provides uniform broadband light to the confocal microscope assembly 200 and the optical detection assembly 300 to image the object 30. The confocal microscope component 200 generates and collects the spectral information of the surface profile, and the optical detection component 300 records the spectral information of the spectral image of the surface profile. The system 20 can be integrated or coupled with an image processing module to generate the surface profile of the object 30 according to the spectral image, such as the aforementioned spectral image 40 or hyperspectral image 50. For example, through the hyperspectral image 50, the subsurface contour and the surface layer thickness of the object 30 other than the surface contour can be viewed.

The spectrum analysis is based on the chromatic aberration principle of the broadband uniform light passing through the confocal microscope assembly 200. The chromatic aberration of the uniform light produces spectral information representing more distinct wavelengths across the height of the surface profile, and the surface profile can be accurately measured based on these wavelengths without vertical scanning. Compared with the slow traditional point-to-point measurement method, the system 20 can achieve high-speed surface profile measurement due to the pinhole device 220 such as the Nipkov disc 226. The entire surface of the object 30 can be scanned and measured seamlessly, thereby eliminating the risk that the area of interest of the object 30 is excluded, and the object 30 can be inspected with higher quality.

Therefore, the system 20 and method 40 can be used for high-speed and accurate surface profile measurement, especially the surface profile of wave shape or discontinuous shape, which can be suitable for various applications, including semiconductor wafers, integrated circuit circuits and precision parts. High-speed automatic surface contour inspection.

With reference to the drawings, the disclosed embodiments of the system 20 and the method 400 for measuring the surface profile of an object are described in detail above. These embodiments are not intended to limit the present disclosure to specific representative examples, but merely illustrate non-limiting examples of the present disclosure. This disclosure is used to solve at least one of the problems and deficiencies of the known technologies mentioned. Although the disclosure only discloses some embodiments here, those skilled in the art should understand that various changes and/or modifications can be made to the disclosed embodiments without departing from the scope of the disclosure according to the disclosure. Therefore, the scope of the disclosure and the scope of the appended claims are not limited to the embodiments disclosed herein.

20: System 30: Object 32: Mechanically movable platform 40: Spectral image 50: Hyperspectral image 100: Light source assembly 100 110: Broadband light source 112: lights 114: optical aperture 116: optical integrating sphere 120: Kohler lighting device 122: Tube lens 200: Confocal microscope components 210: beam splitter 220: pinhole device 222: Pinhole 224: Micro lens 226: Nipkov Disc 230: incident optics group 232: Objective 234: Tube lens 236: Chromatic aberration lens 238: second objective lens 240: drive mechanism 250: Transformation device 300: Optical detection component 302: Single-shot hyperspectral imaging component 310: Optical detector 312: Color camera 314: Hyperspectral camera 320: Detection optics group 322: imaging lens 324: Collimator 326: Relay lens 330: Aperture device 332: Pinhole 334: Micro lens 336: slit aperture 340: Raster 400: Step-by-step flowchart 402-414: Step 500: Observation device 510: The first beam splitter 510 520: second beam splitter 530: eyepiece 540: imaging lens 550: Camera R: Red G: Green B: blue P1, P2: pitch

The first figure is an exemplary schematic diagram of an object surface profile measurement system according to some embodiments of the disclosure, in which the system has a color camera.

The second figure is an example of a flowchart of a method for measuring the surface profile of an object according to some embodiments of the disclosure.

Figures 3 to 5 are schematic diagrams of exemplary pinhole devices of the measurement system according to some embodiments of the present disclosure.

The sixth figure is a schematic diagram of an example of a light source of the measurement system according to some embodiments of the present disclosure.

The seventh figure is a schematic diagram of an example of a spectral image of the object captured by the measurement system according to some embodiments of the present disclosure.

Figure 8 is an exemplary schematic diagram of a measurement system with another configuration architecture according to some embodiments of the disclosure.

Figure ninth is an exemplary schematic diagram of another measurement system with a hyperspectral imaging component according to some embodiments of the present disclosure.

Figure 10 is a schematic diagram illustrating an example of a hyperspectral image of the object captured by the measurement system according to some embodiments of the disclosure.

FIG. 11 is an exemplary schematic diagram of another measurement system having a hyperspectral imaging component and configured for linear scanning according to some embodiments of the present disclosure.

FIG. 12 is a schematic diagram of an example of a hyperspectral image of the object captured by the measurement system using linear scanning according to some embodiments of the present disclosure.

Figure 13 is an exemplary schematic diagram of another measurement system with a hyperspectral imaging component and a Nipkov disk according to some embodiments of the present disclosure.

Figures 14 and 15 are schematic diagrams of examples of the Nipkov disk according to some embodiments of the present disclosure.

Figure 16 is an exemplary schematic diagram of another measurement system with a color camera according to some embodiments of the disclosure.

20: System

30: Object

100: Light source assembly 100

110: Broadband light source

120: Kohler lighting device

200: Confocal microscope components

210: beam splitter

220: pinhole device

230: Human shot optics group

234: Tube lens

236: Chromatic aberration lens

238: second objective lens

240: drive mechanism

300: Optical detection component

310: Optical detector

312: Color camera

320: detection optics

322: imaging lens

R: Red

G: Green

B: blue

Claims (24)

An object surface profile measurement system, which includes: A light source assembly including a broadband light source; A confocal microscope assembly, including: A beam splitter for guiding the uniform light from the broadband light source to the object; A pinhole device comprising an array of pinholes configured to allow the uniform light from the beam splitter to pass through the pinholes to the object; A set of incident optical elements for guiding the uniform light from the pinhole device to the object and causing the uniform light passing through the incident optical elements to cause chromatic aberration; and The pinhole device is configured to allow reflected light from the object to pass through the pinholes to the beam splitter, the reflected light including spectral information of the surface profile based on the chromatic aberration; and An optical detection component, including: An optical detector that receives the reflected light from the beam splitter; and A set of detecting optical elements, which guide the reflected light from the beam splitter to the optical detector; Wherein, the surface profile of the object can be measured according to the spectral information of the reflected light received by the optical detector, and the spectral information represents the height across the surface profile. The object surface profile measurement system according to claim 1, wherein the broadband light source includes: An optical integrating sphere; A group of lights is arranged around the optical integrating sphere, and the optical integrating sphere is configured to integrate the light energy from the lights; and An optical aperture guides the uniform light emitted from the lamps to leave the broadband light source. The object surface profile measurement system according to claim 2, wherein the lights are white light elements configured to emit red light to blue light, or infrared light to ultraviolet light. The object surface profile measurement system according to any one of claims 1 to 3, wherein the pinhole device includes one or more microlens arrays to match the pinhole array, so that each pinhole matches at least one The microlenses, and the microlenses are configured to focus the light from the beam splitter to the individual pinholes. The object surface profile measurement system according to claim 4, wherein the micro lens arrays are arranged on one or both sides of the pinhole device. The object surface profile measurement system according to any one of claims 1 to 5, wherein the confocal microscope assembly includes a driving mechanism for moving the pinhole device in a plane. The object surface profile measurement system according to claim 6, wherein the driving mechanism is configured to move the pinhole device along the X axis and/or the Y axis in a plane. The object surface profile measurement system according to any one of claims 1 to 7, wherein the group of incident optical elements includes: An objective lens to focus light on the object; A tube lens for focusing the reflected light from the object on the pinhole device; and A chromatic aberration lens is arranged between the barrel lens and the objective lens to cause the chromatic aberration of the light. The object surface profile measurement system according to claim 8, wherein the objective lens and the chromatic aberration lens are integrated into a single lens element. The object surface profile measurement system according to any one of claims 1 to 9, wherein the optical detection component is a hyperspectral imaging assembly (hyperspectral imaging assembly) configured to measure the surface profile and subsurface of the object contour. The object surface profile measurement system according to claim 10, wherein the hyperspectral imaging component is a single shot hyperspectral imaging component configured to measure the surface profile and subsurface profile of the object with a single image. The object surface profile measurement system according to claim 11, wherein the single-shot hyperspectral imaging component includes: The optical detector includes a hyperspectral camera; An aperture device, wherein the reflected light from the beam splitter passes through the aperture device to the hyperspectral camera; and A wavelength differentiation device (wavelength differentiation device) is arranged between the aperture device and the hyperspectral camera and used to separate the reflected light; and The group of detecting optical components includes: A relay lens is arranged between the beam splitter and the aperture device; A collimator (collimator) is arranged between the aperture device and the wavelength separation device; and An imaging lens is arranged between the wavelength separation device and the hyperspectral camera and used for focusing the reflected light on the hyperspectral camera. The object surface profile measurement system according to claim 12, wherein the aperture device includes an array of pinholes or a slit aperture. The object surface profile measurement system according to claim 13, wherein the aperture device includes the pinholes of the array and an array of microlenses matching the pinholes of the array, so that each pinhole is matched with one microlens, The micro lens is configured to focus the reflected light from the beam splitter to the individual pinhole. The object surface profile measurement system according to any one of claims 12 to 14, wherein the wavelength division device includes a grating to diffract the reflected light, or an optical beam to diffuse the reflected light . The object surface profile measurement system according to claim 1, wherein The light source assembly includes the broadband light source and an illuminating device, and the illuminating device is used to uniformly guide uniform light from the broadband light source; The confocal microscope components include: The beam splitter and the group of incident optical elements; The pinhole device includes the pinhole array and one or more arrays of microlenses matching the pinhole array, so that each pinhole is matched with at least one microlens, wherein the microlens is used to The light from the beam splitter is focused into the individual pinholes; and A driving mechanism for moving the pinhole device along the X-axis and Y-axis planes; and The optical detection component includes a color camera for measuring the surface contour of the object. The object surface profile measurement system according to claim 1, wherein The light source assembly includes the broadband light source and an illuminating device for guiding uniform light from the broadband light source evenly; The confocal microscope components include: The beam splitter and the set of incident optical elements; and The pinhole device includes the pinhole array and one or more arrays of microlenses matching the pinhole array, so that each pinhole is matched with at least one microlens, wherein the microlens is used to The light from the beam splitter is focused into the individual pinholes; and The optical detection component is a single-shot hyperspectral imaging component configured to measure the surface profile and sub-surface profile of the object. The single-shot hyperspectral imaging component includes: A hyperspectral camera; and An aperture device, wherein the reflected light from the beam splitter passes through the aperture device to the hyperspectral camera, the aperture device includes an array of pinholes and an array of microlenses matching the array of pinholes, and Each of the pinholes is matched with a microlens, and the microlens is configured to focus the reflected light from the beam splitter into the individual pinholes. The object surface profile measuring system according to claim 17, wherein the driving mechanism moves the pinhole device along the X-axis and Y-axis plane. The object surface profile measurement system according to claim 1, wherein The light source assembly includes the broadband light source and a cylindrical lens for focusing the uniform light from the broadband light source into a line beam to linearly scan the object; The confocal microscope components include: The beam splitter and the group of incident optical elements; The pinhole device includes a single row of the pinhole array based on the linear scan and one or more arrays of microlenses matching the single row of pinholes, so that each pinhole is matched with at least one microlens , The micro lens is configured to focus the light from the beam splitter into the individual pinholes; and A driving mechanism that moves the pinhole device parallel to the plane of the single row of pinholes; and The optical detection component is a single-shot hyperspectral imaging component configured to measure the surface profile and sub-surface profile of the object. The single-shot hyperspectral imaging component includes: A hyperspectral camera; and An aperture device, wherein the reflected light from the beam splitter passes through the aperture device to the hyperspectral camera, and the aperture device includes a single row of pinholes for the linear scanning and a pair of the single row of pinholes A single row of microlenses makes each pinhole match one microlens, and the microlens is configured to focus the reflected light from the beam splitter into the individual pinholes. The object surface profile measurement system according to claim 1, wherein The light source assembly includes the broadband light source and a cylindrical lens for focusing the uniform light from the broadband light source into a line beam to linearly scan the object; The confocal microscope components include: The beam splitter and the group of incident optical elements; The pinhole device includes a single row of the pinhole array based on the linear scan and one or more arrays of microlenses matching the single row of pinholes, so that each pinhole is matched with at least one microlens , The micro lens is configured to focus the light from the beam splitter into the individual pinholes; and A driving mechanism that moves the pinhole device parallel to the plane of the single row of pinholes; and The optical detection component is a single-shot hyperspectral imaging component configured to measure the surface profile and sub-surface profile of the object. The single-shot hyperspectral imaging component includes: A hyperspectral camera; and An aperture device, wherein the reflected light from the beam splitter passes through the aperture device to the hyperspectral camera, and the aperture device includes a slit aperture for the linear scanning. The object surface profile measurement system according to claim 1, wherein The light source assembly includes the broadband light source and an illuminating device for guiding uniform light from the broadband light source evenly; The confocal microscope components include: The beam splitter and the set of incident optical elements; and The pinhole device is a Nipkov disc and includes the pinhole array; and A driving mechanism for rotating the pinhole device along the Z axis; and The optical detection component is a single-shot hyperspectral imaging component configured to measure the surface profile and sub-surface profile of the object. The single-shot hyperspectral imaging component includes: A hyperspectral camera; and An aperture device, wherein the reflected light from the beam splitter passes through the aperture device to the hyperspectral camera, the aperture device includes an array of pinholes and an array of microlenses matching the array of pinholes, and Each of the pinholes is matched with a microlens, and the microlens is configured to focus the reflected light from the beam splitter into the individual pinholes. The object surface profile measurement system according to claim 21, wherein the Nipkov disk further includes one or more arrays of microlenses to match the pinhole array, so that each pinhole matches at least one of the pinholes. The micro lens is used to focus the light from the beam splitter into the individual pinholes. The object surface profile measurement system according to claim 22, wherein the microlenses of the arrays are arranged on one or both sides of the pinhole device. The object surface profile measurement system according to any one of claims 21 to 23, wherein the pinholes are circular or square.

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