Line scan three-dimensional sensing system

Abstract

A line-scan three-dimensional sensing system measures the surface profile of an object. In the system, a dispersive optical module (DOM) performs forward optical processing to disperse a polychromatic linear light beam into a gradient narrow-band linear light beam (CNLLB) and focus the CNLLB on different focal planes to form a rainbow light pattern to illuminate a scanned surface of the object. The illuminated object displays an informative band color image (IBCI) containing height information of the scanned surface. The DOM captures the IBCI and performs backward optical processing to optically recombine the captured IBCI to form an elongated light pattern. The backward optical processing is the inverse of the forward processing. A slit spatially filters the elongated light pattern to form an output light ray. By analyzing the spectral content of each point on the output light ray, the height profile of the scanned surface can be obtained.

Description

[0001] List of abbreviations

[0002] 2D

[0003] 3D

[0004] CNLLB graded narrowband linear beam

[0005] DOM Dispersion Optics Module

[0006] FOV (Field of View)

[0007] IBCI includes information in color images.

[0008] LED light-emitting diode

[0009] NIR (Near Infrared)

[0010] PLLB Multicolor Linear Beam

[0011] TIR total internal reflection Technical Field

[0012] This invention relates generally to a line-scanning three-dimensional sensing system for measuring the surface contour of an object. More specifically, the system involved in this invention disperses a multi-color linear beam into a gradually narrowing linear beam and focuses the gradually narrowing linear beam at different heights above a reference surface to form a rainbow light pattern for surface contour measurement. Background Technology

[0013] Currently, glossy surfaces, multi-layered transparent surfaces, and intricate electronic surfaces are the most complex surfaces to be inspected, almost becoming a bottleneck in the field of machine vision. Products such as electronic components, semiconductor wafers, mobile phone cover glass, and automotive metal parts are consistently difficult to inspect. It has been recognized that 2D machine vision cannot meet the requirements, thus necessitating fast and accurate 3D measurement technology. Line-scan 3D sensing is the most advanced technology for inspecting such surfaces.

[0014] Traditional line-scan 3D sensing systems suffer from problems in certain situations. For example, the tilt-axis scanning 3D sensing system disclosed in US 7,936,464 B2 suffers from shadowing issues. Smaller features behind larger objects cannot be detected. Furthermore, deep holes and grooves cannot be measured. Systems using pinhole arrays or digital micromirror device panels, such as those disclosed in US 2020 / 0363619 A1 and DE 102006007172 B4, can be used to measure deep holes and grooves. However, alignment is critical, resolution is limited by the pinhole size, and crosstalk is a significant drawback. Systems using cylindrical lenses and diffraction elements, such as those disclosed in US 8,654,352 B1, also have various problems. Because cylindrical lenses are used, rotational tolerances during lens assembly are critical, leading to stringent requirements for lens alignment. Diffraction elements also introduce zero-order and higher-order diffraction noise.

[0015] There is a need in the field to develop a new line-scan 3D sensing system to address the aforementioned shadowing problem (so that deep holes and grooves can be measured), while also making the system easier to align. Summary of the Invention

[0016] A first aspect of the present invention is to provide a line-scan three-dimensional sensing system for measuring the surface contour of an object.

[0017] The system includes a light source module, a first slit, a DOM, and a second slit. The light source module generates a multicolor beam. The first slit spatially filters the multicolor beam to form a PLLB. The DOM is configured to perform forward optical processing, dispersing the PLLB received from the first slit into a CNLLB, and focusing the CNLLB onto different focal planes to form a rainbow light pattern used to illuminate the scanned surface of the object during surface profilometry, thereby displaying an IBCI on the illuminated object. The IBCI contains height information of the scanned surface. The DOM is further configured to capture the IBCI and perform backward optical processing on the captured IBCI to form an elongated light pattern. The backward optical processing is the reverse of the forward optical processing. The second slit spatially filters the elongated light pattern to form an output ray. By analyzing the spectral content of each point of the output ray, the height profile of the scanned surface can be obtained, and the surface profile can be determined based on the respective height profiles obtained for multiple scanned surfaces of the object.

[0018] Preferably, the DOM includes first and second sets of lenses. The first set of lenses is aligned on a first optical axis. The first set of lenses is configured to disperse the PLLB into the CNLLB and focus the CNLLB onto different focal planes distributed along a predetermined length of the first optical axis to form a rainbow light pattern. The second set of lenses is configured to optically converge the captured IBCI to form an elongated light pattern. The first and second sets of lenses share one or more shared lenses. At least one shared lens is used to simultaneously output the rainbow light pattern and input the IBCI. Therefore, it avoids the burden of aligning the first and second sets of lenses to output the rainbow light pattern and input the IBCI.

[0019] Preferably, the DOM further includes a beam splitter optically coupled to one or more shared lenses and positioned in the first set of lenses, thereby causing the captured IBCI to be replicated into two copies, one of which is directed toward the second slit.

[0020] Preferably, the second lens group includes one or more additional lenses not shared with the first lens group. These one or more additional lenses are disposed between the beam splitter and the second slit for optically processing the captured IBCI before it reaches the second slit. These one or more additional lenses are replicas of corresponding one or more lenses in the first lens group used for optical processing of the PLLB and are disposed between the beam splitter and the first slit.

[0021] In some embodiments, the first slit is configured such that any PLLB emitted to the DOM from any point on the first slit has a first set of principal rays with a divergence angle within 1° when measured based on the first optical axis. Furthermore, the first set of lenses is configured such that any CNLLB received at any point on the rainbow pattern has a second set of principal rays with a convergence angle within 1° when measured based on the first optical axis. The system also includes a platform for positioning an object during surface profile measurement. The platform includes a reference plane on which the object is adapted to be placed. Additionally, the first set of lenses is oriented such that the first optical axis is perpendicular to the reference plane, resulting in a rainbow pattern perpendicular to the reference plane, thereby allowing surface profile measurement even when the scanned surface includes grooves.

[0022] In some embodiments, the light source module is a color mixing light source module including a light source and a color mixing bar. The light source is used to generate original light that collectively provides multicolor light. The color mixing bar is optically coupled to a first slit to provide a multicolor beam to the first slit for spatial filtering. The color mixing bar is elongated in shape to mix the original light to generate a multicolor beam, such that at least a portion of the multicolor beam received by the first slit has substantially uniform color.

[0023] In some embodiments, the light source includes one or more LEDs for collectively generating the original light. Furthermore, the color mixing light source module further includes an asymmetric TIR lens for guiding the original light generated from the one or more LEDs to the color mixing bar. The asymmetric TIR lens has different lengths in the X and Y directions.

[0024] In some embodiments, the light source includes one or more LEDs, each LED having a solar spectral phosphor filler deposited thereon, wherein the solar spectral phosphor filler is formulated to produce a spectrum in at least the 400 nm to 700 nm range. The one or more LEDs are configured to optically excite the solar spectral phosphor filler to generate pristine light, which collectively provides multicolor light. Furthermore, a color mixing rod is optically coupled to the light source to directly receive the pristine light from the light source.

[0025] In some embodiments, the system further includes a grating, an imaging sensor, a collimating lens module, and a condenser lens module. The grating is used to diffract the output light rays, thereby forming a spectral image of the output light rays. The imaging sensor is used to image the spectral image. The spectral content of each point on the output light rays can be determined from the spectral image. The collimating lens module, located between the second slit and the grating, is used to collimate the output light rays before they are diffracted by the grating. The condenser lens module is positioned between the grating and the imaging sensor to focus the spectral image onto the imaging sensor.

[0026] In some embodiments, the system further includes a prism for reflecting the spectral image emitted from the grating onto the condenser module. The prism is configured to reorient the spectral image such that the collimating lens module and the condenser module are oriented perpendicularly to each other, thereby facilitating the alignment and assembly of the collimating lens module and the condenser module.

[0027] In some embodiments, the system further includes a third slit and a two-dimensional line scan camera. The third slit is used to spatially filter a copy of the elongated light pattern received at the third slit to form a second output ray. The two-dimensional line scan camera is used to color image the second output ray, thereby obtaining a two-dimensional image of the object for three-dimensional sensing after scanning multiple scanning surfaces. Furthermore, the DOM further includes a first beam splitter and a second beam splitter. The first beam splitter is disposed in a first lens group to copy the captured IBCI into two copies, one of which is directed to the second slit. The second beam splitter is disposed in the first lens group to copy the captured IBCI into two copies, one of which is directed to the third slit.

[0028] A second aspect of the invention is to provide another line-scan three-dimensional sensing system for measuring the contours of an object surface.

[0029] The system includes a light source module, a first slit, a first DOM, a second DOM, a double-lens module, and a second slit. The light source module generates a multicolor beam. The first slit is optically coupled to the light source module and is used to spatially filter the multicolor beam to form a PLLB. The first dispersive optics module is configured to perform forward optical processing, dispersing the PLLB received from the first slit into a CNLLB, and focusing the CNLLB onto different focal planes to form a rainbow light pattern. The rainbow light pattern is used to illuminate the scanned surface of the object during surface profilometry so that the illuminated object displays an IBCI on the object. The IBCI contains height information of the scanned surface. The second DOM is configured to capture the IBCI and perform backward optical processing, optically converging the captured IBCI into an elongated light pattern. The backward optical processing is the reverse of the forward optical processing. The first and second dispersive optics modules are arranged side-by-side. The double-lens module is configured to reposition the rainbow light pattern generated by the first dispersive optics module to an offset position suitable for positioning the object, and guide the IBCI from the offset position to the second dispersive optics module so that the second dispersive optics module can capture the IBCI. The second slit is used to spatially filter the elongated light pattern to form the output light beam. By analyzing the spectral content of each point of the output light beam, the height profile of the scanned surface can be obtained. Based on the respective height profiles obtained from multiple scanned surfaces of the object, the surface profile can be determined.

[0030] Preferably, the first dispersive optical module includes a first plurality of lenses, while the second dispersive optical module includes a second plurality of lenses. The second plurality of lenses are copies of the first plurality of lenses.

[0031] In some embodiments, the second dispersive optical module further includes a reflector disposed in a second plurality of lenses.

[0032] In some embodiments, the light source module is a color-mixing light source module including a light source and a color mixing bar. The light source is used to generate original light rays that collectively provide multicolor light. The color mixing bar is optically coupled to a first slit to provide a multicolor beam to the first slit for spatial filtering. The color mixing bar is elongated in shape to mix the original light rays to generate a multicolor beam, thereby ensuring that at least a portion of the multicolor beam received by the first slit has substantially uniform color.

[0033] In some embodiments, the light source includes one or more LEDs for collectively generating the primary light. Furthermore, the color-mixing light source module further includes an asymmetric TIR lens for mixing the primary light generated from the one or more LEDs to form an intermediate light output, such that the intermediate light output is substantially uniform in radiant power. The primary light in the intermediate light output is fed into a color-mixing bar. Additionally, the asymmetric TIR lens has different lengths in the X and Y directions.

[0034] In some embodiments, the light source includes one or more LEDs, each LED having a solar spectral phosphor filler deposited thereon, wherein the solar spectral phosphor filler is formulated to produce a spectrum in at least the 400 nm to 700 nm range. One or more LEDs are arranged to optically excite the solar spectral phosphor filler to generate pristine light, which collectively provides multicolor light. Furthermore, a color mixing rod is optically coupled to the light source to directly receive the pristine light from the light source.

[0035] In some embodiments, the system further includes a grating, an imaging sensor, a collimating lens module, and a condenser lens module. The grating is used to diffract the output light rays, thereby forming a spectral image of the output light rays. The imaging sensor is used to image the spectral image. The spectral content of each point of the output light rays can be determined from the spectral image. The collimating lens module, located between the second slit and the grating, is used to collimate the output light rays before they are diffracted by the grating. The condenser lens module is disposed between the grating and the imaging sensor for focusing the spectral image onto the imaging sensor.

[0036] Other aspects of this disclosure are disclosed as illustrated in the following embodiments. Attached Figure Description

[0037] Figure 1 The first line-scan 3D sensing system for measuring the contours of an object surface is demonstrated, wherein the first system uses DOM: generating a rainbow light pattern from PLLB to illuminate the object on the scanned surface, thereby displaying IBCI on the object; and optically converging the captured IBCI into an elongated light pattern, which is then filtered through a second slit to produce an output light with spectral content indicating the height contours of the scanned surface.

[0038] Figure 2 Images showing the elongated light pattern in sub-image (a) and the output light in sub-image (b) demonstrate the filtering effect achieved by the second slit.

[0039] Figure 3 A cross-sectional view of the first color mixing light source module used in the first system is depicted.

[0040] Figure 4 Two cross-sectional views of the XX section and YY section of the first color mixing light source module are depicted.

[0041] Figure 5 A cross-sectional view of the second color mixing light source module is depicted.

[0042] Figure 6A second line-scan 3D sensing system for measuring the surface profile of an object is demonstrated, wherein the second system includes a prism for changing the direction of the spectral image of the output light so that the collimating lens module and the condenser lens module can be easily aligned and assembled in the second system.

[0043] Figure 7 An enlarged view of the prism used in the second system is depicted.

[0044] Figure 8 A third line-scan 3D sensing system for measuring the contours of an object surface is demonstrated, in which the third system uses two independent DOMs to generate rainbow light patterns and optically converge the captured IBCI.

[0045] Figure 9 A fourth line-scan 3D sensing system for measuring the contours of an object surface was demonstrated. This fourth system is a variant of the third system. Its advantage is that the imaging sensor and the condenser module are located away from the light source module, thus avoiding the difficulties of assembling the condenser module into the fourth system and avoiding interference to the imaging sensor due to light leakage that may come from the light source module.

[0046] Figure 10 A fifth line-scan 3D sensing system for measuring the surface contours of an object is demonstrated, with the additional capability of capturing a 2D image of the object.

[0047] Figure 11 A ray tracing diagram was drawn, showing the propagation of the constituent rays in and around the DOM used in the first type of line-scan 3D sensing system.

[0048] Those skilled in the art will understand that the components shown in the accompanying drawings are for simplicity and clarity and are not necessarily depicted to scale. Detailed Implementation

[0049] In this specification and the appended claims, the spectral content or wavelength spectrum of a light beam defines the "color" of the light beam. This spectrum may have one or more wavelengths. If the light beam is visible, the meaning of the color is easily understood. For example, red corresponds to a wavelength of approximately 700 nanometers. In another example, a light beam having a wavelength spectrum uniformly distributed in the visible range of 400 to 700 nanometers is generally considered to have white. The above definition of color extends the concept of color to invisible light. Invisible light beams, such as near-infrared beams, possess colors corresponding to the wavelength content within the near-infrared beam. Furthermore, two beams of invisible light with different wavelengths are considered here to have different colors, even though these two beams are invisible to humans.

[0050] As used herein, a "multicolor beam" is a beam of light having a spectrum composed of multiple wavelengths. This spectrum can be discrete, continuous, or a mixture thereof. A multicolor beam is a superposition of multiple constant narrowband light beams, or can be decomposed into multiple constant narrowband light beams, each of which has a spectrum substantially narrower than the spectrum of the multicolor beam, wherein the spectra of the constant narrowband light beams substantially do not overlap. Each constant narrowband light beam can be visible or invisible, depending on its wavelength content. It is possible that each constant narrowband light beam is a monochromatic beam, i.e., a beam that is practically considered by those skilled in the art to have a single wavelength.

[0051] As used in this article, the "dispersion" of a polychromatic beam refers to the decomposition of the polychromatic beam into its graded narrowband beams and the spatial separation of these graded narrowband beams. For example, if the graded narrowband beams are directed in different directions of propagation, they are spatially separated. To achieve the dispersion of a polychromatic beam, lenses or prisms that exhibit different refractive indices for narrowband beams with different wavelength contents can be used.

[0052] As used in this article, a "linear beam" refers to a beam whose cross-section has a straight shape, wherein the cross-section is perpendicular to the direction of beam propagation. The boundary of the cross-section can be sharp or blurred.

[0053] As used in this article, a "double-pass lens" is a lens used for forward and backward optical paths, where the forward and backward optical paths travel in opposite directions.

[0054] As used in this article, a “double-pass lens module” is an optical module consisting of one or more lenses, each of which is a double-pass lens.

[0055] As used in this article, the "focal plane" is a plane perpendicular to the optical axis containing the focal point.

[0056] In this specification and the appended claims, the term "inverse" in optical processing is interpreted as substantially similar to the inverse of a mathematical function. If optical processing is represented by a conversion rule for converting a first beam into a second beam, then the inverse of optical processing is represented by another conversion rule for converting a second beam into a first beam.

[0057] This document discloses an implementation scheme for a line-scanning 3D sensing system for measuring the surface contour of an object. Essentially, the line-scanning 3D sensing system illuminates the object using a spatial distribution of focused linear beams of different colors to form a color image on the object, wherein the object's height information is encoded into the color image through the spatial distribution of colors on the color image. Specifically, the spatial distribution of the focused linear beams forms a rainbow pattern in the form of a planar light sheet. Thus, a line scan is performed by scanning one line or strip on the object's surface at a time. By performing multiple line scans on different strips on the object's surface, the object's surface contour is measured.

[0058] Figure 1 A first line-scan three-dimensional sensing system 100 (referred to as the first system 100) for measuring the surface profile of an object 95 is shown, according to certain embodiments of the disclosed line-scan three-dimensional sensing system.

[0059] exist Figure 1 The diagram shows a reference frame 80, which defines the x, y, and z directions along the x, y, and z axes. Reference frame 80 is used herein to assist in illustrating different parts or components of various embodiments of the disclosed line-scan three-dimensional sensing system.

[0060] For example, the first system 100 includes a light source module 130, a first slit 121, a DOM 110, and a second slit 122.

[0061] Light source module 130 is used to generate a multicolor beam 131. The multicolor beam 131 is then used to generate a spatial distribution of focused linear beams with different colors to illuminate object 95. Ideally, the radiant power and color of the multicolor beam 131 should be spatially uniform across its cross-section. While maintaining substantial uniformity of color and power in the central region of the cross-section is practical, extending this uniformity to the periphery of the cross-section is often difficult or expensive.

[0062] Advantageously, the first slit 121 is optically coupled to the light source module 130 for spatial filtering of the multicolor beam 131 to form a PLLB 125. The first slit 121 is positioned relative to the light source module 130 such that the peripheral portion of the multicolor beam 131 emitted from the light source module 130 is filtered out. Therefore, the PLLB 125 it produces is substantially uniform in radiant power and color.

[0063] DOM 110 is used to receive PLLB 125 as input from the first slit 121 and output a rainbow light pattern 181 to illuminate object 95 for surface profile measurement. Specifically, DOM 110 is configured to disperse PLLB 125 into CNLLB180 (in... Figure 1(denoted by λ1, λ2, and λ3), and CNLLB 180 is focused on different focal planes outside DOM 110 (denoted by different lines 183a-c of λ1, λ2, and λ3, and along...). Figure 1 The rainbow light pattern 181, which displays a series of different colors, is formed by the z-direction distribution of the CNLLB 180. Since the CNLLB 180 is a linear beam, the rainbow light pattern 181, composed of the CNLLB 180 at focusing positions 183a-c, is a planar light sheet positioned on the xz plane with a predetermined length 184 along the z-direction. On the scanning surface 283 of the object 95, the object 95 is illuminated by the rainbow light pattern 181. The scanning surface 283 is the surface being scanned. The scanning surface 283 is an elongated strip of the outer surface of the object 95, thus achieving a linear scan of the object 95. When the object 95 is illuminated by the rainbow light pattern 181, the illuminated object 95 displays IBCI 282 on the object 95. IBCI 282 contains height information of the scanning surface 283. Specifically, the height information is encoded in the color distribution of IBCI 282. Note that the predetermined length 184 of the rainbow light pattern 181 determines the maximum measurable variation in the height of the object 95.

[0064] Since IBCI 282 is displayed on the outer surface of object 95, the color image is not planar in most cases. To obtain the color distribution of IBCI 282 by directly capturing the IBCI 282 displayed on object 95 using a 2D imaging sensor, the 2D imaging sensor needs to be positioned directly above object 95 along the Z-axis; otherwise, some information about the color distribution will be lost, for example, if object 95 has a deep hole. However, positioning the 2D imaging sensor directly above object 95 is impractical.

[0065] Instead of directly imaging IBCI 282, DOM 110 was configured to capture IBCI from a high-altitude position (in... Figure 1The captured IBCI 182 (denoted by λ2 and referred to as 182) is transmitted elsewhere via DOM 110. Specifically, the displayed IBCI 282 (i.e., the IBCI 282 displayed on object 95) is received by DOM 110 through the same outlet as the output rainbow light pattern 181. Note that PLLB 125 and CNLLB 180 travel along DOM 110 in the opposite direction to the direction of travel of the captured IBCI 182. Thus, when PLLB 125 is processed in a forward optical manner, i.e., dispersed into CNLLBs 180 and focused onto different focal planes 183a-c respectively, the captured IBCI 182 undergoes a backward optical process, which is the reverse of the forward optical process. Since the displayed IBCI 282 can be regarded as a remnant of the rainbow light pattern 181 on the object 95, it is expected that the backward optical processing will convert the captured IBCI 182 into a linear line segment (corresponding to PLLB 125 in the forward optical processing). Figure 2 Subfigure (a) depicts a diagram showing the simulation results, which demonstrate that an elongated light pattern 210 is obtained by processing the captured IBCI 182 with backward optical processing. As a result, DOM 110 optically converges the captured IBCI 182 to form the elongated light pattern 210.

[0066] Unlike the PLLB125, which typically appears as a sharp beam, the elongated light pattern 210, while containing a main center line 215, also has surrounding light signals 216. The main center line 215 is contributed by the rainbow light pattern 181 intersecting the object 95 and contains height information of the scanned surface 283 of the object 95. Since the rainbow light pattern 181 is formed by CNLLB 180 at focus positions 183a-c, stray light from CNLLBs outside the focus also exists around the rainbow light pattern 181. It is believed that the surrounding light signals 216 are due to reflections of stray light from the object 95 and are therefore considered noise.

[0067] To obtain the main centerline 215 from the elongated light pattern 210 while removing the surrounding light signal 216, the second slit 122 is used to spatially filter the elongated light pattern 210 to form the output light ray 220. As a demonstration, Figure 2Subfigure (b) shows a diagram illustrating the output ray 220 obtained by masking the elongated light pattern 210 with the second slit 122. The output ray 220 can be used to obtain the height profile of the scanned surface 283 of the object 95. This height profile can be obtained by analyzing the spectral content of each point of the output ray 220. The surface profile of the object 95 can be determined based on the respective height profiles obtained for multiple scanned surfaces of the object 95.

[0068] Preferably, forward and backward optical processing is achieved by a plurality of lenses 112, 113, and 116 in DOM 110. Specifically, DOM 110 includes a first group of lenses 171 and a second group of lenses 172, wherein the lenses in these two groups are selected from the plurality of lenses 112, 113, and 116. Figure 1 As shown, the first lens group 171 consists of lenses 112 and 113, while the second lens group 172 consists of lenses 113 and 116. Note that the first and second lens groups 171 and 172 share one or more lenses (referred to as shared lens 113). Lenses 112 and 113 of the first lens group 171 are aligned on the first optical axis 111. The first lens group 171 is configured to disperse PLLB 125 into CNLLB 180 and focus CNLLB 180 onto focal planes 183a-c distributed along a predetermined length 184 on the first optical axis 111 to form a rainbow light pattern 181. The second lens group 172 is configured to optically concentrate the captured IBCI 182 into an elongated light pattern 210. Advantageously, one or more shared lenses 113 are used to simultaneously output the rainbow light pattern 181 and input the displayed IBCI 282 (i.e., Figure 1 (Lens 113a shown). Thus, it avoids the burden of aligning the first and second lens groups 171, 172 to output the rainbow light pattern 181 and input the IBCI 282 for display.

[0069] Since both CNLLB 180 and the captured IBCI 182 travel within the shared lens 113, it is necessary to separate the captured IBCI 182 from CNLLB 180 before the captured IBCI 182 (which becomes an elongated light pattern 21) reaches the second slit 122. Therefore, DOM 110 further includes a beam splitter 118 optically coupled to the shared lens 113 and positioned within the first lens group 171, such that the captured IBCI 182 moving within the shared lens 113 is replicated into two copies, one of which is directed to the second slit 122.

[0070] Because the first lens group 171 includes a beam splitter 118, the captured IBCI 182 moves along the path of lens 116 in the second lens group 172, while the PLLB 125 moves along another path along lens 112 in the first lens group 171. Since the forward optical processing of the PLLB 125 is the reverse of the backward optical processing of the captured IBCI 182, the lens 116 (referred to as the additional lens 116 for convenience), arranged between the beam splitter 118 and the second slit 122, can be selected as a replica of the lens 112 (referred to as the corresponding lens 112) arranged between the beam splitter 118 and the first slit 121. Note that while the corresponding lens 112 is aligned with the first optical axis 111, the additional lens 116 is aligned with the second optical axis 117, which is perpendicular to the first optical axis 111.

[0071] As described above, one advantage of DOM 110 is that it avoids the burden of aligning the first and second lens groups 171, 172 to output the rainbow light pattern 181 and input the IBCI 282 for display. Furthermore, the lenses among the plurality of lenses 112, 113, 116 are preferably circular lenses, rather than the cylindrical lenses used in U.S. Patent 8,654,352 B1, thus avoiding the requirement to align cylindrical lenses in DOM 110. DOM 110 only requires aligning the first slit 121 with the first optical axis 111 and the second slit 122 with the second optical axis 117. Therefore, the manufacturing cost of DOM 110 is reduced.

[0072] In the actual implementation of the first system 100, a platform 192 is typically used to position the object 95 during surface profile measurement. The platform 192 includes a reference plane 190 on which the object 95 is adapted to be placed. The reference plane 190 is a flat surface that serves as a reference for measuring the height profile of the object 95. In the first system 100, the first lens group 171 is oriented such that the first optical axis 111 is perpendicular to the reference plane 190. This makes the rainbow light pattern 181 perpendicular to the reference plane 190. Advantageously, even if the scanning surface 283 of the object 95 includes grooves or deep holes, as long as the propagation directions of the CNLLB 180 reaching the rainbow light pattern 181 are nearly parallel, allowing different colors of CNLLB 180 to propagate into the grooves or deep holes for measurement, surface profile measurement is permitted.

[0073] With the help of Figure 11 The description indicates that CNLLB 180 with nearly parallel propagation directions is provided at the rainbow light pattern 181. Figure 11A ray tracing diagram showing the propagation of the constituent rays of PLLB 125 and CNLLBs 180 within and around DOM 110 is drawn. The ray tracing diagram has regions A and B, which are used to show the ray propagation of PLLB 125 around the first slit 121 and the ray propagation of CNLLB 180 near the rainbow pattern 181, respectively. Figure 11 It also includes enlarged views of regions A and B to show the details within them.

[0074] To ensure that the CNLLB 180 is nearly parallel in its propagation direction, it is best to first control the propagation direction of the light rays constituting the PLLB 125. The first slit 121 can be divided into a plurality of points. The PLLB 125 emitted at each point has a field of view (FOV) formed by a cone of light rays. The cone of light rays consists of a set of principal rays and another set of remaining weaker rays, wherein the set of principal rays possesses the dominant portion of the total light energy provided by the cone of light rays. As used herein, a set of principal rays in the cone of light rays is defined as: the set of principal rays accounts for 90% of the total light energy provided by the cone of light rays. Preferably, the PLLB 125 emitted from any point on the first slit 121 to the DOM 110 has a first set of principal rays (e.g., any set of R1-R4) whose divergence angle δ1125, when measured based on the first optical axis 111, is within 1°. Thus, the PLLB 125 is nearly collimated over the entire first slit 121, and the divergence angle δ1125 at any point on the first slit 121 does not exceed 1°. Please note that the first slit 121 may be configured to collimate the multicolor beam 131 as a collimator during the formation of the PLLB 125. For example, the first slit 121 may be formed as a long channel for guiding and limiting the propagation direction of the PLLB 125.

[0075] PLLB 125 is processed by a first set of lenses 171 to form CNLLB 180, which in turn forms a rainbow pattern 181. Since the divergence angle δ1125 of PLLB 125 is within 1°, it is preferable that any CNLLB 180 received at any point on the rainbow pattern 181 has a second set of principal rays (e.g., any set of R1′-R4′) whose convergence angle δ′1180 is within 1° when measured based on the first optical axis 111. Therefore, the rainbow pattern 181 is capable of measuring deep holes and grooves (if any) located on the object 95 without shading issues. Maintaining the convergence angle δ′1180 within 1° can be achieved through a proper configuration of the first set of lenses 171 in DOM 110. In one embodiment, the first set of lenses 171 is configured to have a very long total focal length (like a telescope) for different colors of light, such that the propagation direction of CNLLB 180 from DOM 110 is approximately parallel to the first optical axis 111.

[0076] As described above, the predetermined length 184 of the rainbow light pattern 181 determines the maximum measurable variation in the height of the object 95. In an actual design of the first system 100, the predetermined length 184 is 6 mm for a wavelength spectrum from 400 nm to 700 nm (i.e., the entire visible spectrum). The rainbow light pattern 181 is positioned above the reference plane 190, allowing the rainbow light pattern 181 to be measurable at a working distance (e.g., ...). Figure 11 As shown, D) is between 32 mm (λ1 at wavelength 400 nm) and 38 mm (λ3 at wavelength 700 nm). The angle of the principal ray measured from the first optical axis 111 is less than 1° at the first slit 121 and the object 95, so there is no shadow problem, and the first system 100 can measure deep holes or grooves. The image space numerical aperture is 0.45, therefore, the first system 100 can measure surfaces with a tilt angle greater than 22°. In the design of the first system 100, the plurality of lenses 112, 113, 116 in DOM 110 include at least one dispersive lens pair (e.g., lenses 113b, 113c) for dispersing PLLB 125.

[0077] Other implementation details of the first system 100 are described below.

[0078] In some embodiments, the light source module 130 is a color mixing light source module configured to mix raw light of different colors to form a multicolor beam 131. As described above, ideally, the power and color of the multicolor beam 131 are spatially uniform across its cross-section.

[0079] Figure 3 A cross-sectional view of a first color mixing light source module 130a, which is a first embodiment of a light source module 130, is depicted. Figure 4 Two cross-sectional views of the first color mixing light source module 130a are depicted on the xx and yy sections, serving as a demonstration of beam mixing in the light source module 103a. The first color mixing light source module 130a includes a light source 310, an asymmetric TIR lens 320, and a color mixing bar 330.

[0080] Light source 310 is used to generate a primary light ray 415 that collectively provides multicolor light. Typically, light source 310 includes one or more LEDs 315 for collectively generating the primary light ray 415, although other types of light emitters may also be used. In some embodiments, the one or more LEDs 315 include large-area, high-power LEDs (with dimensions greater than 3 mm in LED width).

[0081] The color mixing rod 330 is optically coupled to the first slit 121 to provide a multicolor beam (reference numeral 350) to the first slit 121 for spatial filtering. The color mixing rod 330 is elongated in shape and is used to mix the original light 415 to produce a multicolor beam 350, thereby making at least a portion of the multicolor beam 350 received by the first slit 121 substantially uniform in color.

[0082] An asymmetric TIR lens 320 is located between the light source 310 and the color mixing bar 330. Functionally, the asymmetric TIR lens 320 is used to guide the raw light 415 generated from one or more LEDs 315 to the color mixing bar 330. The asymmetric TIR lens 320 is used to guide and efficiently transmit the raw light 415 to the color mixing bar 330. Because the color mixing bar 330 is elongated, the asymmetric TIR lens 320 has an asymmetric shape, with different lengths in the X and Y directions.

[0083] The inventors of this invention have determined the following design parameters for the asymmetric TIR lens 320 and the color mixing bar 330 to effectively transmit the original light 415 from the light source 310 to the color mixing bar 330: (a) Lx > Ly, where Lx and Ly are the diameters of the asymmetric TIR lens 320 in the X and Y directions, respectively; (b) Fx > Fy, where Fx and Fy are the focal points of the asymmetric TIR lens 320 in the X and Y directions, respectively; (c) Dx > 10 mm, Dy < 2.5 mm, where Dx and Dy are the lengths of the color mixing bar 330 in the X and Y directions, respectively; and H > 3 × Dx, where H is the height of the color mixing bar 330.

[0084] Figure 5 A cross-sectional view of a second color mixing light source module 130b, which is a second embodiment of the light source module 130, is described. The second color mixing light source module 130b includes a light source 510 and a color mixing bar 530.

[0085] Light source 510 is used to generate primary light rays 511 that collectively provide multicolor light. Light source 510 includes one or more LEDs (e.g., LED 515) for collectively generating the primary light rays 511. Individual LEDs 515 are combined with a solar spectral phosphor filler. The solar spectral phosphor filler is formulated to generate light in the visible spectrum at least from 400 nm to 700 nm. Individual LEDs 515 are arranged to optically excite the solar spectral phosphor filler, thereby enabling one or more LEDs to generate primary light rays 511 that collectively provide multicolor light.

[0086] The color mixing rod 530 is optically coupled to the first slit 121 to provide a multicolor beam (reference numeral 550) for spatial filtering to the first slit 121. The color mixing rod 530 is elongated in shape and is used to mix the original light 511 to generate a multicolor beam 550, ensuring that at least a portion of the multicolor beam 550 received by the first slit 121 has a substantially uniform color. Unlike the first color mixing light source module 130a, the color mixing rod 530 of the second color mixing light source module 130b is optically coupled to the light source 510 to directly receive the original beam 511 from the light source 510.

[0087] As described above, the height profile can be obtained by analyzing the spectral content of each point of the output ray 220. Please refer to... Figure 1 To obtain spectral content, the first system 100 may further include a grating 140 and an imaging sensor 145. The grating 140 is used to diffract the output light 220, thereby forming a spectral image 230 of the output light 220. The spectral image 230 is obtained as a first-order diffraction pattern of the output light 220. Let θ represent the angle at which the first-order diffraction pattern is observed, where θ is measured relative to the second optical axis 117. The imaging sensor 145 is a two-dimensional imaging sensor used for imaging the spectral image 230. The imaging sensor 145 is positioned in the θ direction relative to the second optical axis 117 to image the first-order diffraction pattern, i.e., the spectral image 230. The spectral content of each point of the output light 220 can be determined from the spectral image 230. The first system 100 may further include a collimating lens module 151 and a condenser lens module 152. A collimating lens module 151 is positioned between the second slit 122 and the grating 140 to collimate the output light 220 before it is diffracted by the grating 140. A condenser lens module 152 is disposed between the grating 140 and the imaging sensor 145 to focus the spectral image 230 onto the imaging sensor 145. Those skilled in the art will understand that the collimating lens module 151 and the condenser lens module 152 can be easily designed based on knowledge of the art and the actual requirements for processing the output light 220 and the spectral image 230.

[0088] Figure 6 A second line-scan three-dimensional sensing system 600 (hereinafter referred to as the second system 600) for measuring the surface profile of an object 95 is described according to certain embodiments of the disclosed line-scan three-dimensional sensing system.

[0089] The second system 600 is implemented by any embodiment of the first system 100 and further includes a prism 645 for reflecting the spectral image 230 emitted from the grating 140 to the condenser module 152. The prism 645 is configured to reorient the spectral image 230 so that the collimating lens module 151 and the condenser module 152 are oriented perpendicularly to each other. In contrast, in the first system 100, the condenser module 152 needs to form a predetermined angle θ with the second optical axis 117 in order to receive the spectral image 230 from the grating 140. Therefore, the second system 600 has an advantage over the first system 100 because the second system 600 allows for convenient alignment and assembly of the lens module 151 and the condenser module 152.

[0090] Figure 7 An enlarged view of the prism 645 used to illustrate its design is shown. The prism 645 includes a first surface 751, an inclined plane 752, and a second surface 753. The first surface 751 is adjacent to the grating 140 and is used to receive the spectral image 230. The spectral image 230 is reflected by the inclined plane 752 via TIR. The second surface 753 is adjacent to the condenser lens module 152. The reflected spectral image 230' exits the second surface 753 perpendicularly and enters the condenser lens module 152. Furthermore, a possible additional advantage of using the prism 645 is that it can correct image field curvature distortion caused by the tilted diffraction angle.

[0091] To design prism 645, the tilt angle τ between the inclined plane 752 and the z-direction 730 relative to the reference frame 80 needs to be determined. The z-direction 730 is perpendicular to the second surface 753. The tilt angle τ is determined as follows. According to Snell's law, sinθ = n·sinθ′, where: n is the refractive index of the prism material; θ is the diffraction angle of the grating 140, which is also the incident angle of the spectral image 230 entering prism 645; and θ′ is the corresponding refraction angle. From the geometry of prism 645, since the incident angle is the same as the reflection angle of TIR at the inclined plane 752, we get π / 2 + θ′ = 2τ. Therefore, the tilt angle τ is given by the following formula.

[0092]

[0093] Figure 8 A third line-scan three-dimensional sensing system 800a (referred to as the third system 800a) for measuring the surface profile of an object 95 is described according to certain embodiments of the disclosed line-scan three-dimensional sensing system. The main feature of the third system 800a relative to the first system 100 is that, instead of using a single DOM for simultaneously generating the rainbow light pattern 181 and processing the IBCI 182, it uses two separate DOMs to perform these two functions.

[0094] The third system 800a is developed based on the first system 100 and includes a light source module 130, a first slit 121, and a second slit 122. Details of the light source module 130, the first slit 121, and the second slit 122 have been disclosed above with respect to the first system 100. The third system 800a further includes a first dispersive optical module 810, a second dispersive optical module 820a, and a double-pass lens module 830.

[0095] The light source module 130 is used to generate a multicolor beam 131.

[0096] The first slit 121 is optically coupled to the light source module 130 and is used to spatially filter the multicolor beam 131 to form PLLB 125.

[0097] The first dispersive optics module 810 is configured to perform forward optical processing to disperse the PLLB 125 received from the first slit 121 to the CNLLB 180 and focus the CNLLB 180 on different focal planes to form a rainbow pattern 181′. During surface profilometry, the rainbow pattern 181′ is used to illuminate the scanning surface 283 of the object 95 when it encounters the object 95, so that the illuminated object 95 displays an IBCI 282 on the object 95. The IBCI 282 contains height information of the scanning surface 283. Note that the rainbow pattern 181′ generated by the first dispersive optics module 810 is located at a position where it does not encounter the object 95.

[0098] The second dispersive optical module 820a is configured to capture IBCI 282 and perform backward optical processing to optically converge the captured IBCI 182 into an elongated light pattern 210. Backward optical processing is the reverse of forward optical processing. Note that the first and second dispersive optical modules 810 and 820a are arranged side by side.

[0099] The dual-pass lens module 830 is optically coupled to the first dispersive optical module 810, the object 95, and the second dispersive optical module 820a. Specifically, the dual-pass lens module 830 includes a plurality of lenses 831 configured to reposition the iridescent pattern 181′ generated by the first dispersive optical module 810 to an offset position 890, where the object 95 is positioned, such that the repositioned iridescent pattern 181′ satisfies the object 95. The plurality of lenses 831 are further configured to guide IBCI 282 from the offset position 890 to the second dispersive optical module 820a, enabling the second dispersive optical module 820a to capture IBCI 282.

[0100] The second slit 122 is used to spatially filter the elongated light pattern 210 to form the output light ray 220. By analyzing the spectral content of each point of the output light ray 220, the height profile of the scanned surface 283 can be obtained, and the surface profile can be determined based on the respective height profiles obtained for the multiple scanned surfaces of the object 95.

[0101] Note that, as described above, the first dispersive optical module 810 and the second dispersive optical module 820a are configured to perform forward and backward optical processing, respectively, wherein the backward optical processing is the reverse of the forward optical processing. Typically, the first dispersive optical module 810 and the second dispersive optical module 820a are implemented using a first plurality of lenses 811 and a second plurality of lenses 821, respectively, wherein the second plurality of lenses 821 are copies of the first plurality of lenses 811.

[0102] Similar to the first system 100, the third system 800a may include a grating 140 and an imaging sensor 145. The grating 140 is used to diffract the output light 220, thereby forming a spectral image 230. The spectral image 230 is obtained as a first-order diffraction pattern of the output light 220. The imaging sensor 145 is a two-dimensional imaging sensor used to image the spectral image 230. The imaging sensor 145 is positioned in direction O relative to the second optical axis 117 for imaging the first-order diffraction pattern, i.e., the spectral image 230. The spectral content of each point of the output light 220 can be determined from the spectral image 230. The third system 800a may further include a collimating lens module 151 and a condenser lens module 152. The collimating lens module 151 is positioned between the second slit 122 and the grating 140 for collimating the output light 220 before it is diffracted by the grating 140. A condenser module 152 is disposed between the grating 140 and the imaging sensor 145 for focusing the spectral image 230 onto the imaging sensor 145.

[0103] Similar to the first system 100, the light source module 130 of the third system 800a can be a color mixing light source module. The light source module 130 of the third system 800a can be implemented as any embodiment of the first color mixing light source module 130a or the second color mixing light source module 130b.

[0104] Figure 9A fourth line-scan three-dimensional sensing system 800b (abbreviated as fourth system 800b) for measuring the surface profile of an object 95 is described according to certain embodiments of the disclosed line-scan three-dimensional sensing system. The fourth system 800b is a variation of the third system 800a. It should first be noted that in the third system 800a, the imaging sensor 145 is close to the light source module 130, and the condenser lens module 152 is rigidly tilted at a diffraction angle to receive the spectral image 230. This can lead to difficulties in assembling the condenser lens module 152 into the third system 800a, and in avoiding interference to the imaging sensor 145 due to possible light leakage from the light source module 130. The fourth system 800b advantageously moves the imaging sensor 145 and the condenser lens module 152 away from the light source module 130.

[0105] The fourth system 800b is implemented by any embodiment of the third system 800a, but the fourth system 800b modifies the second dispersive optical module 820a. The modified second dispersive optical module 820b used in the fourth system 800b is implemented together with the second plurality of lenses 821 in the original second dispersive optical module 820a. Furthermore, the second dispersive optical module 820b is further equipped with a reflector 925, which is disposed within the second plurality of lenses 821, for reflecting the captured IBCI 182, thereby changing the path of the IBCI 182 captured in the second dispersive optical module 820b by a certain angle, preferably 90°. As a result, the imaging sensor 145 and the condenser lens module 152 are moved away from the light source module 130.

[0106] Figure 10 A fifth line-scan three-dimensional sensing system 1000 (hereinafter referred to as the fifth system 1000) for measuring the surface profile of an object 95 is described according to certain embodiments of the disclosed line-scan three-dimensional sensing system. The fifth system 1000 is developed based on the first system 100 and has the additional function of capturing 2D images of the object 95.

[0107] The fifth system 1000 is implemented by any embodiment of the first system 100, but the fifth system 1000 modifies the DOM 110 and introduces additional elements related to capturing 2D images.

[0108] Additional elements include a third slit 1123 and a 2D line scan camera 1200. The third slit 1123 is used to spatially filter a copy 1210 of the elongated light pattern received at the third slit 1123 to form a second output light ray 1220. The 2D line scan camera 1200 is used to color image the second output light ray 1220. After scanning multiple scanning surfaces for 3D sensing, a 2D image of object 95 can be obtained.

[0109] The DOM 1110 modified and used in the fifth system 1000 includes multiple lenses 112, 113, 116, and 1116 for performing forward and backward optical processing and outputting a specific signal for creating a 2D image. Specifically, the DOM 1110 includes a first group of lenses 171, a second group of lenses 172, and a third group of lenses 1173, wherein these three groups of lenses are selected from the multiple lenses 112, 113, 116, and 1116. Figure 10 As shown, the first lens group 171 consists of lenses 112 and 113, the second lens group 172 consists of lenses 113 and 116, and the third lens group 1173 consists of lenses 113 and 1116. Note that these three lens groups 171, 172, and 1173 share one or more lenses (referred to as shared lens 113). Lenses 112 and 113 of the first lens group 171 are aligned on the first optical axis 111. The first lens group 171 is configured to disperse PLLB 125 into CNLLB 180 and focus CNLLB 180 onto focal planes 183a-c, respectively, along a predetermined length 184 on the first optical axis 111, to form a rainbow light pattern 181. The second lens group 172 is configured to optically converge the captured IBCI 182 to form an elongated light pattern 210. The third lens group 1173 is configured to deliver a copy 1210 of an elongated light pattern to the third slit 1123, which is substantially similar to the elongated light pattern 210 received at the second slit 122.

[0110] Since both CNLLB 180 and the captured IBCI 182 travel within the shared lens 113, it is necessary to separate the captured IBCI 182 from CNLLB 180 before the captured IBCI 182 (which becomes an elongated light pattern 210) reaches the second slit 122 and before the captured IBCI 182 (which becomes a copy 1210 of the elongated light pattern) reaches the third slit 1123. Therefore, DOM 1110 further includes a first beam splitter 1118 and a second beam splitter 1119. The first beam splitter 1118 is optically coupled to the shared lens 113 and positioned within the first lens group 171, thereby causing the captured IBCI 182 moving within the shared lens 113 to be replicated into two copies, one of which is guided to the second slit 122. Similarly, the second beam splitter 1119 is optically coupled to the shared lens 113 and positioned in the first lens group 171, such that the captured IBCI 182 traveling in the shared lens 113 is replicated in two copies, one of which is guided to the third slit 1123.

[0111] Based on the above analysis of the first system 100, those skilled in the art will understand that: the lens 116 arranged between the first beam splitter 1118 and the second slit 122 can be selected as a copy of the lens 112 (referred to as the corresponding lens 112) arranged between the second beam splitter 1119 and the first slit 121; and the lens 1116 arranged between the second beam splitter 1119 and the third slit 1123 can also be selected as a copy of the corresponding lens 112.

[0112] Some notes applicable to all embodiments of the present invention, including the first, second, third, fourth and fifth systems 100, 600, 800a, 800b, 1000, are given below.

[0113] In this invention, all CNLLBs used to form the rainbow light pattern 181 can be visible or invisible; therefore, the entire rainbow light pattern 181 can be visible (e.g., if viewed against a sheet of paper) or invisible. Using a visible rainbow light pattern has the practical advantage of making it easier for personnel to set up and fine-tune the disclosed line-scan 3D sensing system. On the other hand, an invisible rainbow light pattern (e.g., near-infrared based) is useful if it is undesirable to attract the attention of nearby people during surface profile measurement. The invention also includes cases where a portion of the CNLLB 180 is invisible.

[0114] Since backward optics is the reverse of forward optics, the main center line 215 of the elongated light pattern 210 has a size close to PLLB 125. Those skilled in the art will understand that enlarging or reducing the size of the elongated light pattern 210 generated by a certain DOM does not change the operating principle of the disclosed line-scan three-dimensional sensing system in surface profile measurement. Those skilled in the art will be able to modify the disclosed embodiments without substantial difficulty to implement this scaling step according to the teachings disclosed in this specification and the accompanying drawings. The scaled backward optics is obtained as a cascade of backward optics with a multiplicative block of scaling the size of the elongated light pattern 210. In view of the above discussion, the scaled backward optics is considered equivalent to the backward optics within the scope of this invention.

[0115] This invention may be embodied in other specific forms without departing from its spirit or essential characteristics. Therefore, embodiments of the invention should be considered illustrative rather than restrictive in all respects. The scope of the invention is defined by the appended claims rather than the foregoing description, and thus all variations within the meaning and equivalence of the claims are to be included therein.

Claims

1. A line-scanning three-dimensional sensing system for measuring the contour of an object surface, the system comprising: The light source module is used to generate multicolor line beams; The light source module is a color mixing light source module, and includes: Light sources are used to generate primordial light rays, which together provide polychromatic light; and A color mixing bar optically coupled to a first slit, the color mixing bar being used to provide a multicolor beam to the first slit for spatial filtering; the color mixing bar is elongated in shape and is used to mix the original light to generate the multicolor beam, so that at least a portion of the multicolor beam received by the first slit has a substantially uniform color. Used to spatially filter the multicolor beam to form a first slit for a multicolor linear beam; The dispersive optics module is configured as follows: The forward optical processing is performed to disperse the multicolor linear beam received from the first slit into a gradient narrowband linear beam, and to focus the gradient narrowband linear beam onto different focal planes to form a rainbow light pattern; the rainbow light pattern is used to illuminate the scanned surface of the object during surface profile measurement, so that the illuminated object displays an information-containing color image on the object, the information-containing color image containing height information of the scanned surface; Capture the information-containing color image; and A backward optical processing is performed to optically converge the captured information-containing color image to form a thin, elongated light pattern; wherein the backward optical processing is the reverse of the forward optical processing; and The second slit is used to spatially filter the elongated light pattern to form an output light ray. The height profile of the scanned surface is obtained by analyzing the spectral content of each point of the output light ray, and the surface profile is determined based on the respective height profiles obtained for multiple scanned surfaces of the object.

2. The system according to claim 1, wherein the dispersive optics module comprises: A first set of lenses aligned on a first optical axis is configured to disperse the multicolor linear beam into the gradient narrowband linear beam and focus the gradient narrowband linear beam onto different focal planes distributed along a predetermined length of the first optical axis to form the rainbow light pattern. as well as The second set of lenses is configured to optically converge the captured information-containing color image to form the elongated light pattern, wherein the first set of filters and the second set of lenses share one or more shared lenses, at least one of which is used to simultaneously output the rainbow light pattern and input the information-containing color image, thereby avoiding the burden of aligning the first set of lenses and the second set of lenses to output the rainbow light pattern and input the information-containing color image.

3. The system of claim 2, wherein the dispersive optics module further includes a beam splitter optically coupled to the one or more shared lenses and positioned within the first set of lenses to reproduce the captured informational color image in two copies, one of which is directed to the second slit.

4. The system of claim 3, wherein the second set of lenses includes one or more additional lenses not shared with the first set of lenses, the one or more additional lenses being arranged between the beam splitter and the second slit for optically processing the captured informational color image before it reaches the second slit, wherein the one or more additional lenses are copies of corresponding one or more lenses in the first set of lenses used for optically processing the multicolor linear beam and arranged between the beam splitter and the first slit.

5. The system according to claim 2, wherein: The first slit is configured such that the multicolor linear beam emitted to the dispersive optical module at any point on the first slit has a first set of principal rays whose divergence angle is within 1° when measured based on the first optical axis; The first set of lenses is configured such that the gradient narrowband linear beam received at any point on the rainbow light pattern has a second set of principal rays whose convergence angle is within 1° when measured based on the first optical axis; The system also includes a platform for positioning the object during the surface profile measurement; the platform includes a reference plane on which the object is adapted to be placed. as well as The first set of lenses is oriented such that the first optical axis is perpendicular to the reference plane, causing the rainbow light pattern to be perpendicular to the reference plane, thereby allowing the surface profile to be measured even when the scanning surface includes grooves.

6. The system according to claim 1, wherein: The light source includes one or more light-emitting diodes (LEDs) for jointly generating the original light; and The color mixing light source module also includes an asymmetric total internal reflection lens for guiding the original light generated from the one or more light-emitting diodes to the color mixing bar, wherein the asymmetric total internal reflection lens has different lengths in the X and Y directions.

7. The system according to claim 1, wherein: The light source includes one or more light-emitting diodes, each of which is deposited with a solar spectral phosphor filler, the solar spectral phosphor filler being formulated to produce a spectrum in the range of at least 400 nm to 700 nm; the one or more light-emitting diodes are configured to optically excite the solar spectral phosphor filler to generate the original light, these original light rays collectively providing the polychromatic light; as well as The color mixing bar is optically coupled to the light source to directly receive the original light from the light source.

8. The system according to claim 1, further comprising: A grating is used to diffract the output light rays, thereby forming a spectral image of the output light rays; An imaging sensor is used to image the spectral image, and the spectral content of each point of the output light can be determined by the spectral image; A collimating lens module positioned between the second slit and the grating is used to collimate the output light before the output light is diffracted by the grating; and A condenser lens module located between the grating and the imaging sensor is used to focus the spectral image onto the imaging sensor.

9. The system according to claim 8, further comprising: A prism is used to reflect the spectral image emitted from the grating onto the condenser module. The prism is configured to reorient the spectral image such that the collimating lens module and the condenser module are perpendicular to each other, thereby facilitating the alignment and assembly of the collimating lens module and the condenser module.

10. The system according to claim 2, further comprising: A third slit is used to spatially filter a copy of the elongated light pattern received at the third slit to form a second output light ray; as well as A two-dimensional line scan camera is used to perform color imaging on the second output light; Accordingly, after scanning the multiple scanning surfaces, a two-dimensional image of the object can be obtained for three-dimensional sensing. The dispersive optics module further includes: A first beam splitter, positioned within the first set of lenses, is configured to duplicate the captured informational color image into two copies, one of which is directed to the second slit; and A second beam splitter is disposed in the first group of lenses to reproduce the captured informational color image in two copies, one of which is directed to the third slit.

11. The system of claim 10, further comprising: A grating is used to diffract the output light rays, thereby forming a spectral image of the output light rays; An imaging sensor is used to image the spectral image, and the spectral content of each point of the output light can be determined by the spectral image; A collimating lens module positioned between the second slit and the grating is used to collimate the output light before the output light is diffracted by the grating; and A condenser lens module located between the grating and the imaging sensor is used to focus the spectral image onto the imaging sensor.

12. A line-scanning three-dimensional sensing system for measuring the contour of an object surface, the system comprising: The light source module is used to generate multi-color light beams; The light source module is a color mixing light source module, and includes: Light sources are used to generate primordial light rays, which together provide polychromatic light; and A color mixing bar optically coupled to a first slit, the color mixing bar being used to provide a multicolor beam to the first slit for spatial filtering; the color mixing bar is elongated in shape and is used to mix the original light to generate the multicolor beam, so that at least a portion of the multicolor beam received by the first slit has a substantially uniform color. The first slit, optically coupled to the light source module, is used to spatially filter the multicolor beam to form a multicolor linear beam. A first dispersive optics module is configured to perform forward optical processing to disperse the multicolor linear beam received from the first slit into a graded narrowband linear beam and focus the graded narrowband linear beam onto different focal planes to form a rainbow light pattern; this rainbow light pattern is used to illuminate the scanned surface of the object during surface profilometry, thereby displaying an informational color image on the illuminated object, the informational color image containing height information of the scanned surface; The second dispersive optical module is configured to capture the information-containing color image and perform backward optical processing to optically converge the captured information-containing color image to form an elongated light pattern; wherein the backward optical processing is the reverse of the forward optical processing, and the first dispersive optical module and the second dispersive optical module are arranged side by side. A dual-pass lens module is configured to reposition the rainbow pattern generated by the first dispersive optics module to an offset position suitable for positioning the object, and guide the information-containing color image from that offset position to the second dispersive optics module, allowing the second dispersive optics module to capture the information-containing color image; and The second slit is used to spatially filter the elongated light pattern to form an output light ray. The height profile of the scanned surface is obtained by analyzing the spectral content of each point of the output light ray, and the surface profile is determined based on the respective height profiles obtained for multiple scanned surfaces of the object.

13. The system according to claim 12, wherein: The first dispersive optical module includes a first plurality of lenses; and The second dispersive optical module includes a second plurality of lenses; wherein the second plurality of lenses are copies of the first plurality of lenses.

14. The system of claim 13, wherein the second dispersive optical module further comprises a reflector disposed in the second plurality of lenses.

15. The system according to claim 12, wherein: The light source includes one or more light-emitting diodes (LEDs) for jointly generating the original light; and The color mixing light source module further includes an asymmetric total internal reflection lens for mixing the original light generated from the one or more light-emitting diodes to form an intermediate light output, such that the radiant power of the intermediate light output is substantially uniform; the original light in the intermediate light output is fed into the color mixing bar, wherein the asymmetric total internal reflection lens has different lengths in the X and Y directions.

16. The system according to claim 12, wherein: The light source includes one or more light-emitting diodes, each of which is deposited with a solar spectral phosphor filler, the solar spectral phosphor filler being formulated to produce a spectrum in the range of at least 400 nm to 700 nm; the one or more light-emitting diodes are configured to optically excite the solar spectral phosphor filler to generate the original light, these original light rays collectively providing the polychromatic light; as well as The color mixing bar is optically coupled to the light source to directly receive the original light from the light source.

17. The system of claim 12, further comprising: A grating is used to diffract the output light rays, thereby forming a spectral image of the output light rays; An imaging sensor is used to image the spectral image, and the spectral content of each point of the output light can be determined by the spectral image; A collimating lens module positioned between the second slit and the grating is used to collimate the output light before the output light is diffracted by the grating; and A condenser lens module located between the grating and the imaging sensor is used to focus the spectral image onto the imaging sensor.

Images