Three-dimensional measurement device and method based on spectral dispersion

Abstract

The present invention discloses a three-dimensional measuring device based on spectral dispersion, comprising: a line light source component for outputting a line of incident light; a dispersion objective lens component for dispersing the line incident light in the axial direction, so that incident light of different wavelengths are respectively focused on corresponding measuring points at different heights of the measured object, and receiving outgoing light of different wavelengths reflected from the measuring points; a filtering component, comprising: a pinhole array, located on the focal plane of the outgoing light, so that the outgoing light reflected after focusing on different measuring points is focused in the corresponding pinholes; a moving mechanism, so that the pinhole array can move along the field of view direction of the outgoing light in the focal plane; a spectroscopic imaging component, receiving the outgoing light passing through the pinholes when the pinhole array is located at different moving positions, and obtaining image information of different measuring points on the measured object corresponding to different moving positions. It can solve the problem that the existing three-dimensional measuring equipment needs to use a row of holes array to filter stray light, and the field of view resolution is low due to the limitation of the row of holes period.

Description

Technical Field

[0001] The present invention relates to the technical field of three-dimensional information measurement of objects, and in particular to a three-dimensional measurement device based on spectral dispersion and a three-dimensional measurement method based on spectral dispersion. Background Art

[0002] Imaging techniques for measuring three-dimensional (3D) macrostructures are becoming increasingly mature, especially in the optics, electronics, and semiconductor industries for advanced product development and quality control.

[0003] Generally based on the principle of spectral confocal, a white light source is used to generate wide-band dispersed light after being split by a dispersion element. The dispersed light is then focused on the surface of the workpiece to be measured through a lens, forming a dispersed red band with a special spatial distribution near the measured surface. Light of different spectra is focused within different height ranges. When the sample has a certain 3D morphology, different colors of light are focused at different heights, and light of different wavelengths is reflected back into the optical path. The wavelength of the reflected light is measured by the dispersion and spectrum detection components, and the reflected light component can be known. Since different heights correspond to different colors of reflected light, the height and morphology of 3D samples in one dimension can be detected through the reflection spectrum. Through the scanning device, 3D measurement of the entire surface of the sample can be achieved.

[0004] However, in existing 3D devices for dispersive spectral measurement, in order to avoid the influence of stray light, an array of holes is generally adopted to filter out the influence of background light and surrounding interference light. However, this method is limited by the spacing between each row of holes (hole period). The highest field of view resolution of the measuring equipment is the period of the hole row, resulting in a low field of view resolution, which is difficult to meet the detection scenarios with higher image resolution. Summary of the invention

[0005] In order to overcome the defects of the above-mentioned prior art, an embodiment of the present invention provides a three-dimensional measurement device based on spectral dispersion and a three-dimensional measurement method based on spectral dispersion, which can solve the problem that the existing three-dimensional measurement equipment needs to use a hole array to filter out stray light, and the field of view resolution is low due to the limitation of the hole period.

[0006] Specifically, the present invention provides a three-dimensional measurement device based on spectral dispersion, comprising: a line light source component, a dispersion objective lens component, a filtering component and a spectroscopic imaging component; the line light source component is used to output a line of incident light; the dispersion objective lens component is used to disperse the line incident light in the axial direction, so that the line incident light of different wavelengths are respectively focused on corresponding measurement points at different heights of the measured object, and receive the outgoing light of different wavelengths reflected by the measurement points; the filtering component comprises: a semi-transparent and semi-reflective mirror, which is arranged between the line light source component and the dispersion objective lens component along the optical path, and transmits the incident light of the line light source component to the measuring point ... The invention relates to a method for detecting an incident light and reflecting the outgoing light; a pinhole array, which is provided with a plurality of pinholes arranged at intervals and located on the focal plane of the outgoing light, so that the outgoing light reflected after focusing on different measuring points is focused in the corresponding pinholes; a moving mechanism, which is mechanically connected to the pinhole array, so that the pinhole array can move in the focal plane along the field of view direction of the outgoing light; and the spectroscopic imaging component is used to receive the outgoing light passing through the pinholes when the pinhole array is in different moving positions, and obtain image information of different measuring points on the object under test corresponding to the different moving positions.

[0007] In one embodiment of the present invention, the small holes are evenly spaced at a preset distance, and the small hole array can reciprocate within a moving range from an initial position to the preset distance.

[0008] In one embodiment of the present invention, within a line scanning cycle, the spectroscopic imaging component obtains first image information corresponding to a first set of measuring points on the object to be measured when the pinhole array is located at an initial position, and obtains second image information corresponding to a second set of measuring points on the object to be measured when the pinhole array is located at 1 / 2 of the preset distance from the initial position.

[0009] In one embodiment of the present invention, the pinhole array moves 1 / n of the preset distance each time from the initial position, and after moving to n-1 / n of the preset distance, the next movement returns to the initial position, so that the spectroscopic imaging component can obtain n groups of image information corresponding to n groups of measurement points equidistantly spaced from each other on the object under test within one line scanning cycle.

[0010] In one embodiment of the present invention, the pinhole array moves 1 / n of the preset distance each time from the initial position, moves to n-1 / n of the preset distance within one line scanning cycle, and moves 1 / n of the preset distance each time back to the initial position within the next scanning cycle, so that within each line scanning cycle, the spectroscopic imaging component obtains n groups of image information corresponding to n groups of measurement points equidistantly spaced from each other on the object to be measured within one scanning cycle.

[0011] In one embodiment of the present invention, when the object to be measured is scanned, it moves at a uniform speed relative to the measuring device in a direction perpendicular to the line light source, the scanning time between two adjacent measuring points is Δt, the scanning speed is v, then the scanning resolution is vΔt, the spacing between the pinholes on the pinhole array is d, then the field of view resolution of the pinhole array after n movements is d / n, and when vΔt=d / n is controlled, the spectroscopic imaging component obtains standard image information that is not stretched or compressed.

[0012] In addition, an embodiment of the present invention proposes a three-dimensional measurement method based on spectral dispersion, including: providing incident light and dispersing it in the axial direction so that the incident light of different wavelengths are respectively focused on corresponding measurement points at different heights of the object to be measured; focusing the outgoing light of different wavelengths reflected after focusing on the measurement point on the corresponding small holes on the small hole array; moving the small hole array in the focal plane of the outgoing light along the field of view direction of the outgoing light, so that the spectroscopic imaging component receives the outgoing light passing through the small holes when the small hole array is in different moving positions, and obtains image information of different measurement points on the object to be measured corresponding to the different moving positions.

[0013] In one embodiment of the present invention, the pinhole array is moved within the focal plane of the outgoing light along the field of view direction of the outgoing light, comprising: the pinholes are evenly spaced at a preset distance, and the pinhole array moves back and forth within a moving range from an initial position to the preset distance.

[0014] In one embodiment of the present invention, the step of making the spectroscopic imaging component receive the outgoing light rays passing through the pinholes when the pinhole array is in different moving positions to obtain image information of different measuring points on the object to be measured corresponding to the different positions includes: the pinhole array moves 1 / n of the preset distance from the initial position each time, and after moving to n-1 / n of the preset distance, moves back to the initial position the next time, so that the spectroscopic imaging component obtains n groups of image information corresponding to n groups of measuring points equidistant from each other on the object to be measured within one line scanning cycle; or the pinhole array moves 1 / n of the preset distance from the initial position each time, moves to n-1 / n of the preset distance within one line scanning cycle, and moves 1 / n of the preset distance back to the initial position each time in the next scanning cycle, so that the spectroscopic imaging component obtains n groups of image information corresponding to n groups of measuring points equidistant from each other on the object to be measured within each line scanning cycle.

[0015] In one embodiment of the present invention, when the object to be measured is scanned, it moves at a uniform speed relative to the measuring device in a direction perpendicular to the line light source, the scanning time between two adjacent measuring points is Δt, the scanning resolution is vΔt, the spacing between the pinholes on the pinhole array is d, and the field of view resolution of the pinhole array after n movements is d / n. When vΔt is controlled to be less than d / n, the spectroscopic imaging component obtains image information in a compressed state, and when vΔt is equal to d / n, the spectroscopic imaging component obtains standard image information that is not stretched or compressed.

[0016] It can be seen from the above that the above embodiments of the present invention may have one or more of the following beneficial effects:

[0017] (1) By setting a moving mechanism to drive the pinhole array to move along the field of view direction of the outgoing light in the focal plane, image information of different measurement points on the object under test corresponding to different moving positions can be obtained when the pinhole array is at different moving positions. Compared with the method of using a single pinhole array to filter out stray light, the scanning resolution can be significantly improved to meet the detection scene with high image resolution requirements, and the problem of complex equipment structure and increased cost caused by using multiple groups of pinhole arrays can be avoided;

[0018] (2) According to the line scanning cycle of the object to be measured, the pinhole array is set to reciprocate within a preset distance of the pinhole interval. By customizing the moving position of the pinhole array when collecting spectral images in each reciprocating motion cycle, the resolution of the three-dimensional measurement device can be adjusted, thereby improving the measurement accuracy;

[0019] (3) Since the object to be measured moves relative to the measuring device in the direction perpendicular to the line light source during scanning, a 3D topography image of normal proportion can be obtained by setting the scanning resolution to be the same as the filtering resolution of the pinhole array. By adjusting the relationship between the scanning resolution and the filtering resolution, a stretched 3D topography image or a compressed 3D topography image of corresponding proportion can be obtained, which is suitable for more measurement scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0021] Figure 1 A schematic structural diagram of a three-dimensional measurement device based on spectral dispersion provided by an embodiment of the present invention;

[0022] Figure 2 A schematic diagram of the movement state of a small hole array provided in an embodiment of the present invention;

[0023] Figure 3 A schematic diagram of the moving state of another small hole array provided in an embodiment of the present invention;

[0024] Figure 4 A flow chart of a three-dimensional measurement method based on spectral dispersion provided in an embodiment of the present invention.

[0025] Description of Reference Numerals

[0026] 11: Linear light source assembly; 12: Dispersion objective lens assembly; 13: Filter assembly; 131: Semi-transparent and semi-reflective mirror; 132: Pinhole array; 133: Moving mechanism; 14: Spectral imaging assembly;

[0027] S1 to S3: Steps of the three-dimensional measurement method based on spectral dispersion. DETAILED DESCRIPTION

[0028] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other. The present invention will be described below with reference to the accompanying drawings and in combination with the embodiments.

[0029] In order to enable ordinary technicians in the field to better understand the technical solution of the present invention, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments, and all should belong to the protection scope of the present invention.

[0030] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are applicable to distinguishing similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchangeable where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition. The terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or are proprietary to these processes, methods, products or devices.

[0031] It should also be noted that the division of multiple embodiments in the present invention is only for the convenience of description and should not constitute a special limitation. The features in various embodiments can be combined and referenced to each other without contradiction.

[0032] [First embodiment]

[0033] like Figure 1 As shown, the first embodiment of the present invention provides a three-dimensional measurement device based on spectral dispersion, for example, including: a line light source component 11, a dispersion objective lens component 12, a filtering component 13, and a spectroscopic imaging component 14.

[0034] Among them, the line light source component 11, for example, includes a slit light source, which outputs high-brightness linear incident light. Furthermore, the incident light, for example, passes through a lens combination and reaches the dispersion objective lens component 12. The lens combination includes one or more lenses for modulating the optical path of the incident light to improve the collimation and brightness of the light.

[0035] The dispersive objective lens assembly 12 is used to disperse the incident light, and the light of different wavelengths after dispersion is focused on the corresponding measuring point of the object to be measured along the direction of the line light source, and receives the outgoing light of different wavelengths formed by the reflection of the measuring point. Figure 1 As shown in , the dispersive objective lens assembly 12 includes a plurality of lens assemblies. By controlling parameters such as the thickness of each lens and the distance between the lenses, the incident light of different wavelengths can be expanded in the axial direction to obtain light of target wavelengths λ1, λ2 and λ3, which are respectively focused on the measuring points of the height h1, height h2 and height h3 of the measured ball, and are reflected by the measured ball to form outgoing light of different wavelengths and return to the dispersive objective lens assembly 12.

[0036] The filter assembly 13 is provided with a semi-transparent and semi-reflective mirror 131, a pinhole array 132 and a moving mechanism 133, and the semi-transparent and semi-reflective mirror 131 is arranged between the line light source assembly 11 and the dispersive objective lens assembly 12 along the optical path. The incident light reaches the dispersive objective lens assembly 12 after passing through the semi-transparent and semi-reflective mirror 131, and the outgoing light returns to the dispersive objective lens assembly 12 and is reflected by the semi-transparent and semi-reflective mirror 131.

[0037] The pinhole array 132 is provided with a plurality of pinholes which are arranged at intervals and are located on the focal plane of the outgoing light, so that the outgoing light reflected after being focused on different measuring points is focused in the corresponding pinholes.

[0038] As mentioned above, the position information of the object to be measured carried by the outgoing light with wavelengths of λ1, λ2 and λ3 is recorded as (x1, h1), (x2, h2) and (x3, h3) respectively, and the outgoing light is focused to the plane where the pinhole array 132 is located after passing through the dispersion objective lens assembly 12. In particular, the outgoing light of different wavelengths can only be converged to a sufficiently small size in the corresponding pinholes on the pinhole array 132. For example, the outgoing light of wavelength λ1 is focused on the pinhole x1`, and the outgoing light of wavelengths λ2 and λ3 is focused on the pinholes x2` and x3` ​​respectively. For different pinholes, the light of non-target wavelength will diverge more and more as the wavelength deviates from the target wavelength, and therefore will be blocked and filtered out by the pinhole mask array plate 132.

[0039] It is worth mentioning that the shapes of the small holes on the small hole array include but are not limited to: circle, triangle and parallelogram, and the arrangement can be regular uniform spacing, or irregular arrangement, such as gradually increasing or decreasing spacing. By controlling the spacing, diameter and other parameters between the small holes, it can be used to filter the target wavelength of light reflected by the target object point, and the present invention is not limited to this.

[0040] The spectroscopic imaging component 14 is used to receive the outgoing light passing through the pinhole array 132, and focus the outgoing light of different wavelengths on the image plane coordinates corresponding to the pinholes and the measuring points. The imaging plane mentioned is, for example, the imaging plane of the camera photosensitive element. For example, the position information of the object to be measured carried by the outgoing light with a wavelength of λ1 is (x1, h1), and the image plane coordinate point focused on the imaging plane after passing through the pinhole x1` on the pinhole array 132 is (x1``, y1). The position information of the object to be measured carried by the outgoing light with a wavelength of λ2 is (x2, h2), and the image plane coordinate point focused on the imaging plane after passing through the pinhole x2` on the pinhole array 132 is (x2``, y2). Similarly, for example, if n points are sampled on a scanning line of the object to be measured, the position information of the object to be measured carried by the outgoing light with a wavelength of λn is (xn, hn), and the image plane coordinate point focused on the imaging plane after passing through the pinhole xn` on the pinhole array 132 is (xn``, yn).

[0041] Furthermore, the pinhole array 132 is mechanically connected to the moving mechanism 133 so that the pinhole array 132 can move in the focal plane of the outgoing light along the field of view direction of the outgoing light. Since the linear light source forms a scan line on the object to be measured after dispersion, the direction of the scan line is the direction of the linear light source, that is, the field of view direction of the incident light, and the direction mapped to the pinhole array 132 is the field of view direction of the outgoing light. The moving mechanism 133 mentioned is, for example, a displacement platform based on MEMS or piezoelectric ceramics. Figure 1 As shown in the figure, when the object to be measured is scanned and measured, it moves relative to the entire measuring device along the direction perpendicular to the line light source. The distance between two adjacent scanning lines is a scanning cycle. Within a scanning cycle, the pinhole array 132 moves up and down, for example, in the direction perpendicular to the line light source. During the scanning process, the outgoing light rays passing through the pinhole array 132 at different moving positions can carry the height information of different corresponding measuring points on the object to be measured.

[0042] In this way, by setting up a moving mechanism to drive the pinhole array to move in the focal plane along the field of view direction of the outgoing light, image information of different measurement points on the object under test corresponding to different moving positions can be obtained when the pinhole array is in different moving positions. Compared with the method of using a single pinhole array to filter out stray light, the scanning resolution can be significantly improved to meet the detection scenarios with high image resolution requirements, and the problem of complex equipment structure and increased cost caused by the use of multiple groups of pinhole arrays can be avoided.

[0043] In one embodiment, the small holes on the small hole array 132 are evenly spaced at a preset distance, such as Figure 2 As shown in , the preset distance between the pinholes is d, that is, the resolution of the pinhole filter is d. In addition, the movement of the pinhole array 132 is, for example, reciprocating movement within the movement range from the initial position to the preset distance d, which can prevent the pinhole array 132 from continuously moving and causing the object to miss the measurement points that need to be sampled during the moving scanning process.

[0044] Furthermore, the spectroscopic imaging component 14 obtains the first image information corresponding to the first measurement point on the object to be measured, for example, each time the pinhole array 132 moves from the initial position to 1 / 2 of the preset distance d; and each time the pinhole array 132 moves back to the initial position, it obtains the second image information corresponding to the second measurement point on the object to be measured. Since the pinholes on the pinhole array 132 are evenly spaced, the first measurement points and the second measurement points sampled by it on the object to be measured are also evenly spaced. In this way, the filtering resolution achieved by the pinhole array 132 is d / 2, which doubles the original filtering resolution.

[0045] It should be noted that the three-dimensional measuring device of the present invention and the object to be measured are in relative motion, that is, the three-dimensional measuring device performs line scanning on the object to be measured with a fixed scanning period, and the scanning period corresponds to the movement period of the pinhole array. That is, within one period of the three-dimensional measuring device performing line scanning on the object to be measured, the pinhole array needs to move for one period to obtain images corresponding to n groups of measurement points. There can be multiple movement paths of the pinhole array. For example, after the pinhole array moves n-1 times in one direction from the initial position, it directly returns to the initial position quickly once. This is one period of the pinhole array, and no imaging is performed during the return process; or the pinhole array moves n-1 times in one direction as one period, and n images corresponding to one scanning period are obtained. The return process still moves n-1 times, which is another period of the pinhole array, and n images corresponding to the next scanning period are obtained.

[0046] Specifically, the pinhole array 132 moves 1 / n of the preset distance each time from the initial position, and after moving to n-1 / n of the preset distance d, the next movement returns to the initial position, so that the spectroscopic imaging component 14 obtains n groups of image information corresponding to n groups of measurement points equidistantly spaced from each other on the object under test within one line scanning cycle. In this way, the filtering resolution achieved by the pinhole array 132 is d / n, which increases the original filtering resolution by n times. Therefore, by customizing the moving position of the pinhole array when collecting spectral images in each reciprocating motion cycle, the resolution of the three-dimensional measurement device can be adjusted, thereby improving the accuracy of the measurement.

[0047] In addition, the pinhole array 132 can also move 1 / n of the preset distance each time from the initial position, move to n-1 / n of the preset distance within one scanning cycle, and move 1 / n of the preset distance each time to return to the initial position within the next line scanning cycle. Similarly, the spectroscopic imaging component can obtain n groups of image information corresponding to n groups of measurement points equidistantly spaced from each other on the object to be measured within each line scanning cycle.

[0048] Furthermore, when measuring the object to be measured, for example, the object is scanned at a constant speed v, and the scanning time between two adjacent measuring points is Δt, then the scanning resolution is vΔt. In order to ensure that the obtained detection image is not stretched or compressed, the filtering resolution of the pinhole array must also be vΔt. Since the field of view resolution of the pinhole array after n movements is d / n, when vΔt>d / n, the spectroscopic imaging component 14 obtains image information in a stretched state, when vΔt<d / n, the spectroscopic imaging component 14 obtains image information in a compressed state, and when vΔt=d / n, the spectroscopic imaging component 14 obtains image information in a normal state without stretching or compression.

[0049] For example, at time t+Δt / 2, the MEMS mechanism is used to move the pinhole array 132 in one direction by d / 2 to collect a spectral image. At time t+Δt, the pinhole array 132 is moved back by d / 2 to the initial position, and the spectral image is collected again. Then, the filtering resolution of the pinhole array 132 is doubled. At the same time, the scanning speed is modified to v / 2, and the scanning resolution is also increased by 1 times, and image information of a normal state without stretching or compression is obtained. Of course, the scanning speed v can also be maintained without modification. At this time, the scanning resolution is twice the filtering resolution, and the spectroscopic imaging component 14 collects a 3D morphology image of the stretched state.

[0050] It should be noted that in other embodiments, the pinhole array 132 may also be moved in a non-uniform speed manner, as long as the pinholes on the pinhole array 132 reach the moving position corresponding to the measuring point before the measuring point to be sampled on the measured object appears within the scanning field of view. Figure 3As shown, for example, the pinhole array collects spectral images at the d / 2 moving position, the 3 / d moving position and the initial position. Before each measurement point corresponding to the pinhole at the d / 2 moving position on the object to be measured appears within the field of view, the pinhole array 132 is moved to the d / 2 moving position; similarly, before each measurement point corresponding to the pinhole at the d / 3 moving position and the initial position on the object to be measured appears within the field of view, the pinhole array 132 is moved to the d / 3 moving position and the initial position, and image information in a normal state is obtained at this time. If the measurement point corresponding to the pinhole at a certain moving position on the object to be measured appears within the field of view, and the pinhole array 132 has not moved to the moving position, the measurement point will be missed and a stretched 3D topography image will be obtained; conversely, if the pinhole array 132 exceeds the moving position, a higher density of measurement points will be collected to obtain a compressed 3D topography image.

[0051] In this way, by adjusting the movement mode of the pinhole array 132 and the scanning mode of the object to be measured, the relationship between the filtering resolution of the pinhole array and the scanning resolution of the object to be measured can be controlled, and a 3D morphology image with a certain proportion of stretching, compression or normal proportion can be customized, which is suitable for more detection scenarios.

[0052] In summary, a three-dimensional measuring device based on spectral dispersion proposed in an embodiment of the present invention drives the pinhole array to move along the field of view direction of the outgoing light in the focal plane by setting a moving mechanism. When the pinhole array is in different moving positions, image information of different measuring points corresponding to different moving positions on the object to be measured can be obtained. Compared with the method of using a single pinhole array to filter out stray light, the scanning resolution can be significantly improved to meet the detection scene with high image resolution requirements, and the problem of complex device structure and increased cost caused by using multiple groups of pinhole arrays can be avoided; the pinhole array is set to reciprocate within a preset distance between the pinholes, and the moving position of the pinhole array when collecting the spectral image in each reciprocating motion cycle is customized, so that the resolution of the three-dimensional measuring device can be adjusted, thereby improving the measurement accuracy; since the object to be measured moves relative to the measuring device along the direction of the linear light source when scanning, a 3D topography image of normal proportion is obtained by setting the scanning resolution to be the same as the filtering resolution of the pinhole array, and a stretched 3D topography image or a compressed 3D topography image of corresponding proportion can be obtained by adjusting the relationship between the scanning resolution and the filtering resolution, which is suitable for more measurement scenarios.

[0053] [Second embodiment]

[0054] like Figure 4As shown, the second embodiment of the present invention proposes a three-dimensional measurement method based on spectral dispersion, for example, including steps S1 to S3. Among them, step S1 provides incident light and disperses it in the axial direction, so that the incident light of different wavelengths is respectively focused on the corresponding measurement points at different heights of the object to be measured; step S2 focuses the outgoing light of different wavelengths reflected after focusing on the measurement point on the corresponding small holes on the small hole array; step S3 moves the small hole array in the focal plane of the outgoing light along the field of view direction of the outgoing light, so that the spectroscopic imaging component receives the outgoing light passing through the small holes when the small hole array is in different moving positions, and obtains the image information of different measurement points on the object to be measured corresponding to the different moving positions.

[0055] Furthermore, the method of moving the pinhole array in the focal plane of the outgoing light along the field of view direction of the outgoing light comprises: the pinholes are evenly spaced at a preset distance, and the pinhole array moves back and forth within a moving range from an initial position to the preset distance.

[0056] Further, the method of making the spectroscopic imaging component receive the outgoing light passing through the pinholes when the pinhole array is in different moving positions to obtain image information of different measuring points on the object under test corresponding to the different positions includes: the pinhole array moves 1 / n of the preset distance from the initial position each time, and after moving to n-1 / n of the preset distance, moves back to the initial position the next time, so that the spectroscopic imaging component obtains n groups of image information corresponding to n groups of measuring points equidistant from each other on the object under test within one line scanning cycle; or the pinhole array moves 1 / n of the preset distance from the initial position each time, moves to n-1 / n of the preset distance within one line scanning cycle, and moves 1 / n of the preset distance back to the initial position each time in the next scanning cycle, so that the spectroscopic imaging component obtains n groups of image information corresponding to n groups of measuring points equidistant from each other on the object under test within each line scanning cycle.

[0057] Furthermore, when the object to be measured is scanned, it moves at a uniform speed relative to the measuring device along the direction of the line light source, and the scanning time between two adjacent measuring points is Δt, then the scanning resolution is vΔt, and the spacing between the pinholes on the pinhole array is d, then the field of view resolution of the pinhole array after n movements is d / n, and when vΔt>d / n, the spectroscopic imaging component obtains image information in a stretched state, when vΔt<d / n, the spectroscopic imaging component obtains image information in a compressed state, and when vΔt=d / n, the spectroscopic imaging component obtains image information in a normal state without stretching or compression.

[0058] It is worth mentioning that the three-dimensional measurement method based on spectral dispersion proposed in the second embodiment of the present invention is applicable to the three-dimensional measurement device based on spectral dispersion proposed in the aforementioned first embodiment. The specific three-dimensional measurement device based on spectral dispersion can refer to the system described in the first embodiment, and will not be described here for the sake of brevity. The beneficial effects of the three-dimensional measurement device based on spectral dispersion provided in this embodiment are the same as the beneficial effects of the three-dimensional measurement method based on spectral dispersion provided in the first embodiment.

[0059] In addition, it can be understood that the aforementioned embodiments are only exemplary descriptions of the present invention. Under the premise that the technical features do not conflict, the structures do not contradict, and the purpose of the present invention is not violated, the technical solutions of the various embodiments can be arbitrarily combined and used in combination.

[0060] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A three-dimensional measurement device based on spectral dispersion, characterized in that: include: Linear light source assembly, dispersion objective lens assembly, filtering assembly and spectroscopic imaging assembly; The line light source assembly is used to output a line of incident light; The dispersion objective lens assembly is used to disperse the incident line light in the axial direction, so that the incident line light of different wavelengths is focused on corresponding measuring points at different heights of the measured object, and receive outgoing light of different wavelengths reflected by the measuring points; The filtering component comprises: A semi-transparent and semi-reflective mirror is arranged between the line light source assembly and the dispersion objective lens assembly along the optical path, transmitting the incident light and reflecting the outgoing light; A pinhole array is provided with a plurality of pinholes arranged at intervals and located on the focal plane of the outgoing light, so that the outgoing light reflected after being focused on different measuring points is focused in the corresponding pinholes; A moving mechanism, mechanically connected to the pinhole array, so that the pinhole array can move in the focal plane along the field of view direction of the outgoing light; The spectroscopic imaging component is used to receive the outgoing light rays passing through the pinholes when the pinhole array is at different moving positions, and obtain image information of different measuring points on the object to be measured corresponding to the different moving positions; The small holes are evenly spaced at a preset distance; In one line scanning cycle, the spectroscopic imaging component obtains first image information corresponding to a first set of measuring points on the object under test when the pinhole array is located at an initial position, and obtains second image information corresponding to a second set of measuring points on the object under test when the pinhole array is located at a distance from the initial position to 1 / 2 of the preset distance; or The pinhole array moves from the initial position by 1 / n of the preset distance each time, and moves back to the initial position after moving to n-1 / n of the preset distance, so that the spectroscopic imaging component obtains n groups of image information corresponding to n groups of measurement points equidistantly spaced on the object under test within one line scanning cycle; or The pinhole array moves 1 / n of the preset distance each time from the initial position, moves to n-1 / n of the preset distance within one line scanning cycle, and moves 1 / n of the preset distance each time to return to the initial position within the next line scanning cycle, so that the spectroscopic imaging component obtains n groups of image information corresponding to n groups of measurement points equidistantly spaced from each other on the object to be measured within each line scanning cycle.

2. The three-dimensional measurement device based on spectral dispersion according to claim 1, characterized in that: The small hole array can reciprocate within a moving range from an initial position to the preset distance.

3. The three-dimensional measurement device based on spectral dispersion according to claim 1, characterized in that: When the object to be measured is scanned, it moves at a uniform speed relative to the measuring device in a direction perpendicular to the linear light source. The scanning time between two adjacent measuring points is Δt, and the scanning speed is v, then the scanning resolution is vΔt, and the spacing between the pinholes on the pinhole array is d. Then the field of view resolution of the pinhole array after n movements is d / n. When vΔt=d / n is controlled, the spectroscopic imaging component obtains standard image information that is not stretched or compressed.

4. A method for applying the three-dimensional measurement device based on spectral dispersion as claimed in any one of claims 1 to 3, characterized in that: include: Providing incident light and spreading it in the axial direction so that the incident light of different wavelengths is focused on corresponding measuring points at different heights of the object to be measured; Focusing the outgoing light rays of different wavelengths reflected after focusing on the measuring point into the corresponding small holes on the small hole array respectively; The pinhole array is moved within the focal plane of the outgoing light along the field of view direction of the outgoing light, so that the spectroscopic imaging component receives the outgoing light passing through the pinholes when the pinhole array is in different moving positions, and image information of different measuring points on the object under test corresponding to the different moving positions is obtained.

5. The three-dimensional measurement method based on spectral dispersion according to claim 4, characterized in that: The step of moving the pinhole array within the focal plane of the outgoing light along the field of view direction of the outgoing light comprises: The small holes are evenly spaced at a preset distance, and the small hole array reciprocates within a moving range from an initial position to the preset distance.

Images