Surface detection method based on 3D laser camera
By designing multiple exit interfaces in the laser module of a three-dimensional laser camera, the laser light intersects and tilts at the internal intersection points, the problems of insufficient light and speckle in arc-surface glass detection are solved, and high-quality curved surface detection and imaging are achieved.
Patent Information
- Application Number
- CN202110874447.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2021-07-30
- Publication Date
- 2025-02-14
- Estimated Expiration
- 2041-07-30
AI Technical Summary
When scanning curved glass, existing three-dimensional laser cameras have a single laser direction, which leads to weak light when the observation angle deviates, making it impossible to image, and the light is prone to local interference and speckle, which affects image processing.
By designing a laser module, the first and second type of exit interfaces are used to make the laser light intersect at multiple internal light intersections, and multiple intersections are generated at the second type of exit interfaces. The laser light tilts to the center to ensure that the light is waiting Test the surface evenly irradiation.
It realizes the acquisition of sufficient reflected light during surface detection, solves the problems of insufficient light and speckle, and improves the imaging quality of the detection.
Smart Images

Figure CN113587815B_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of three-dimensional laser cameras, and more specifically, to a surface detection method based on a three-dimensional laser camera. Background Art
[0002] 3D laser cameras are widely used in industrial production. For example, in consumer electronic products such as mobile phones, more and more curved glass displays are appearing. This places higher demands on the quality inspection of curved glass during production and manufacturing. Such inspection requirements mainly include inspection of the surface quality of curved edges, such as scratches, and inspection of the cutting quality of curved edges, such as missing corners and edge size tolerance exceeding limits.
[0003] The reflected light on the surface of general objects can be divided into ambient light, specular reflection light and diffuse reflection light. Generally, rough and matte surfaces mainly show diffuse reflection, while objects with high surface gloss such as glass mainly show specular reflection in addition to transmitted light.
[0004] like Figure 1 As shown, from the Phong model, it can be seen that as the angle α increases, the observable light intensity at the observation point gradually weakens.
[0005] In existing 3D laser cameras, the laser emits light in a single direction, such as parallel light. Because the local normal of the scanned object is uncertain, when scanning an object with a relatively high mirror reflection coefficient, if the angle of the observation point (CMOS camera) deviates greatly from θ (that is, the angle α is too large), the light received by the camera end will be too weak to form an image.
[0006] For example, when scanning curved glass, if parallel light is incident, the light on both sides of the laser line (corresponding to the two sides of the curved surface) will be reflected by the glass surface to the two sides of the camera and cannot be well received by the CMOS sensor.
[0007] For example Figure 2 As shown in the figure below, because laser is monochromatic, local interference is easy to occur on the surface of the object, resulting in severe speckle. As shown in the figure below, it seriously affects the image processing and extraction of laser lines. Summary of the invention
[0008] In order to address the shortcomings of the prior art, the present application provides a surface detection method based on a three-dimensional laser camera, comprising the following steps: making a laser light generated by a laser source emit in parallel along a first direction; making the parallel emitted laser light incident on multiple first-type exit interfaces so that the laser light passing through the multiple first-type exit interfaces intersects at multiple internal light intersections respectively; making the laser light after passing through the internal light intersections incident on a second-type exit interface so that the portion of the laser light located at the edge is tilted toward a direction close to the center and generates multiple laser light intersections on the second-type exit interface.
[0009] Furthermore, the first type of exit interfaces are repeatedly arranged in a second direction perpendicular to the first direction.
[0010] Further, in the second direction, the first-type exit interfaces are all located within the range of the second-type exit interfaces.
[0011] Furthermore, a radius of curvature of the first type of exit interface is less than or equal to a radius of curvature of the second type of exit interface.
[0012] Furthermore, the first type of output interface at least includes a curved surface convex toward the optical output direction of the laser.
[0013] Furthermore, the second type of output interface at least includes a curved surface convex toward the optical output direction of the laser.
[0014] Furthermore, the first type of exit interface is formed on a cylindrical mirror.
[0015] Furthermore, the second type of exit interface is formed on another cylindrical mirror.
[0016] Furthermore, the surface detection method based on the three-dimensional laser camera also includes the following steps:
[0017] The laser light passing through the second type of exit interface is projected onto the curved surface to be measured.
[0018] Furthermore, the surface detection method based on the three-dimensional laser camera also includes the following steps:
[0019] The laser light reflected by the curved surface to be measured is made incident on an image sensor.
[0020] The benefit of the present application lies in that it provides a surface detection method based on a three-dimensional laser camera for obtaining sufficient reflected light during surface detection. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] The drawings constituting a part of this application are used to provide a further understanding of this application, so that other features, purposes and advantages of this application become more obvious. The schematic embodiment drawings and their descriptions of this application are used to explain this application and do not constitute an improper limitation on this application. In the drawings:
[0022] Figure 1 This is a schematic diagram of the principle of the Phong model;
[0023] Figure 2 This is a schematic diagram of speckle caused by interference when detecting a curved surface;
[0024] Figure 3is a schematic diagram of the stereoscopic structure of a three-dimensional laser camera suitable for curved surface detection and an object to be detected according to an embodiment of the present application;
[0025] Figure 4 yes Figure 3 The internal structure diagram of a 3D laser camera suitable for curved surface detection is shown;
[0026] Figure 5 yes Figure 3 The schematic diagram of the optical structure of the laser module and the laser light in the three-dimensional laser camera suitable for curved surface detection is shown;
[0027] Figure 6 is a schematic diagram of the dimensions of a laser module according to an embodiment of the present application;
[0028] Figure 7 is a partial structural schematic diagram of a laser module according to a second embodiment of the present application;
[0029] Figure 8 is a partial structural schematic diagram of a laser module according to a third embodiment of the present application;
[0030] Fig. 9 is a partial structural schematic diagram of a laser module according to a fourth embodiment of the present application;
[0031] Fig.10 is a partial structural schematic diagram of a laser module according to a fifth embodiment of the present application;
[0032] Fig.11 It is a block diagram of the main steps of the surface detection method based on a three-dimensional laser camera according to the present application.
[0033] Meaning of the reference symbols:
[0034] A three-dimensional laser camera 100 suitable for curved surface detection, a camera housing 101, a laser module 102, a lens module 103, an image sensor 104, a parallel light source device 105, a first optical device 106, a second optical device 107, a laser source 108, a collimating lens 109, a beam expander lens 110, a parallel light lens 111, a unit lens 112, a converging lens 113, a first type of exit interface 114, a first type of incident interface 115, a second type of exit interface 116, and a second type of incident interface 117;
[0035] Curved object 200;
[0036] A first optical device 301, a second optical device 302, a second type of exit interface 303, an exit arc surface 3031, and an exit plane 3032;
[0037] A first optical device 401, a second optical device 402, a central lens 4021, and an edge lens 4022;
[0038] A first optical device 501, a second optical device 502, a second type of exit interface 503, an exit inclined surface 5031, and an exit plane 5032;
[0039] A first optical device 601, a second optical device 602, a second type of incident interface 603, and a second type of exit interface 604;
[0040] D1 is the first direction, D2 is the second direction. DETAILED DESCRIPTION
[0041] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present application.
[0042] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present application described here. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.
[0043] In the present application, the terms "upper", "lower", "left", "right", "front", "back", "top", "bottom", "inner", "outer", "middle", "vertical", "horizontal", "lateral", "longitudinal" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings. These terms are mainly used to better describe the present application and its embodiments, and are not used to limit the indicated devices, elements or components to have a specific orientation, or to be constructed and operated in a specific orientation.
[0044] In addition, some of the above terms may be used to express other meanings in addition to indicating orientation or positional relationship. For example, the term "on" may also be used to express a certain dependency or connection relationship in some cases. For those of ordinary skill in the art, the specific meanings of these terms in this application can be understood according to specific circumstances.
[0045] In addition, the terms "installed", "set", "provided with", "connected", "connected", and "socketed" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection, or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be an internal connection between two devices, elements, or components. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.
[0046] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.
[0047] like Figure 1 As shown, the three-dimensional laser camera suitable for curved surface detection of the present application includes: a camera housing, a laser module, a lens module and an image sensor. Among them, the laser module, the lens module and the image sensor are fixedly installed in the camera housing. The central axis of the laser module and the central axis of the lens module are obliquely intersected, that is, arranged into a triangular structure of a general three-dimensional laser camera to realize the function of laser line scanning imaging detection.
[0048] like Figures 3 to 5 As shown, the specific improvement of the present application lies in the laser module. Specifically, the laser module of the present application includes: a parallel light source device, a first optical device and a second optical device.
[0049] The parallel light source device is used to generate and output a laser beam located in a laser plane and having an emission direction parallel to the first direction ( Figure 5 The first optical device is used to change the direction of the laser light so that the laser light intersects at multiple internal light intersections after passing through the first optical device; the second optical device is used to change the direction of the laser light again so that the laser light has a gradually changing and different exit direction after passing through the second optical device.
[0050] As a preferred solution, the parallel light source device includes: a laser source, a collimating lens, a beam expanding lens and a parallel light lens.
[0051] The laser light generated by the laser source passes through the collimating lens to form a laser beam, and the laser beam passes through the beam expanding lens to be diffused into scattered laser lines, and the scattered laser lines pass through the parallel light lens to form parallel laser light. The laser source collimating lens, beam expanding lens and parallel light lens in the parallel light source device are all well known to those skilled in the art, and will not be described in detail here. As a further preferred embodiment, the parallel light lens is constructed as a cylindrical mirror.
[0052] As an alternative, the laser source, the collimating lens, and the beam expander lens can be constructed as a whole, and the collimating light lens is constructed as a whole with the first optical device and the second optical device.
[0053] Reference Figure 5 As shown, the first optical device is arranged between the parallel light source device and the second optical device so that a portion of the laser light emitted from the second optical device and located at the edge is tilted toward a direction close to the center.
[0054] Specifically, the first optical device has or forms a plurality of first-type exit interfaces, and the first-type exit interfaces are curved surfaces whose generatrix is perpendicular to the laser plane. The first-type exit interfaces are along the second direction ( Figure 5 The first optical device has or forms a first type of incident interface, which is a plane perpendicular to the laser plane.
[0055] As a specific implementation scheme, the first optical device is composed of a plurality of unit lenses repeatedly arranged in the second direction, each unit lens is constructed as a part of a cylindrical lens, specifically, a section plane parallel to the central axis of the cylindrical lens (perpendicular to Figure 5 After the cylindrical mirror is divided by a plane (i.e., the plane of the paper), the part with a smaller curvature becomes a unit lens (it may also be a case where the curvature is equally divided), and the cylindrical surface of the unit lens serves as the aforementioned first-type exit interface, and the cross section formed after cutting serves as a part of the first-type incident interface. The end faces of multiple unit lenses are aligned as an overall plane to form the aforementioned first-type incident interface. In this way, it is equivalent to one first-type incident interface corresponding to multiple exit interfaces. As an extended solution, the cylindrical surface of the unit lens may also be other curved surface shapes besides a cylinder. That is, the unit lens and the converging lens are generalized cylindrical mirrors, and their cylindrical portions are divided into various curved surfaces including cylindrical surfaces. The cylindrical mirror referred to in the present application is also a generalized cylindrical mirror, and is not just a cylindrical mirror whose cylindrical surface is a cylindrical surface.
[0056] Specifically, the curved surface of the first type of exit interface protrudes toward the second optical device so that the internal light intersection point of the laser light is located between the first type of optical device and the second type of optical device.
[0057] In addition, by setting the distance from the first type of exit interface to the second type of incident interface, the intersection point (internal light intersection point) of the laser light for the first time is located between the first type of exit interface and the second type of incident interface. Figure 5 As shown, the laser light incident on the second type of incident interface is divergent.
[0058] As a preferred solution, Figure 6 As shown, in the first direction, the distance L3 from the first type of exit interface to the second type of incident interface (ie, the distance between the unit lens and the convergent lens in the second direction) ranges from 10 mm to 100 mm.
[0059] As an optional option, the value range of L3 is 10 mm to 20 mm, 20 mm to 30 mm, 30 mm to 40 mm, and 40 mm to 50 mm.
[0060] As an optional option, the value range of L3 is 20 mm to 80 mm, 30 mm to 70 mm, or 40 mm to 60 mm.
[0061] As a preferred solution, the value range of L3 is 10 mm to 15 mm, and the specific value of L3 is 13.2 mm.
[0062] On the other hand, the second optical device has or forms a second type of exit interface, the second type of exit interface is a generatrix (perpendicular to Figure 5 The second optical device has or forms a second type of incident interface, which is a plane perpendicular to the laser plane.
[0063] As a specific solution, the second optical device is constructed as a converging lens similar in shape to the unit lens, that is, a part of a cylindrical lens, except that the converging lens is larger in size, that is, the maximum value of the curvature radius of the output interface of the unit lens is smaller than the maximum value of the curvature radius of the converging lens.
[0064] As a preferred solution, in the second direction, the size of the second type of incident interface is greater than or equal to the size of two or more first type exit interfaces. As a preferred solution, in the second direction, all unit lenses fall within the range of the converging lens. That is, the size of the whole formed by the multiple unit lenses in the second direction is less than or equal to the size of the converging lens in the second direction.
[0065] As a preferred solution, Figure 5 and Figure 6 As shown, the dimension L1 of the emission interface of the converging lens in the second direction (ie, the dimension of the second type of emission interface in the second direction) ranges from 5 mm to 50 mm.
[0066] As an optional solution, the value range of L1 is 10 mm to 20 mm, 20 mm to 30 mm, 30 mm to 40 mm, and 40 mm to 50 mm.
[0067] As an optional option, the value range of L1 is 10 mm to 50 mm, 20 mm to 40 mm, or 25 mm to 35 mm.
[0068] As a preferred solution, the value range of L1 is 25 mm to 30 mm, and the specific value of L3 is 26 mm.
[0069] The dimension L2 of the output interface of the converging lens in the first direction ranges from 5 mm to 50 mm.
[0070] As an optional solution, the value range of L2 is 10 mm to 20 mm, 20 mm to 30 mm, 30 mm to 40 mm, and 40 mm to 50 mm.
[0071] As an optional option, the value range of L2 is 10 mm to 50 mm, 20 mm to 40 mm, or 25 mm to 35 mm.
[0072] As a preferred solution, the value range of L2 is 5 mm to 10 mm, and the specific value of L3 is 5 mm.
[0073] As a preferred solution, a dimension L5 of the cross section of the unit lens in the second direction ranges from 0.5 mm to 5 mm.
[0074] As an optional option, the value range of L5 is 0.5 mm to 1 mm, 1 mm to 2 mm, 2 mm to 3 mm, 3 mm to 4 mm, and 4 mm to 5 mm.
[0075] As an optional option, the value range of L5 is 1 mm to 5 mm, 2 mm to 4 mm, or 2.5 mm to 3.5 mm.
[0076] As a preferred solution, the value range of L5 is 3 mm to 3.5 mm, and the specific value of L3 is 3.2 mm.
[0077] As a further preferred solution, the dimension L4 of the first type incident interface in the second direction (which is also the dimension of the whole formed by the plurality of unit lenses in the second direction) ranges from 5 mm to 50 mm.
[0078] As an optional option, the value range of L4 is 5 mm to 20 mm, 20 mm to 30 mm, 30 mm to 40 mm, and 40 mm to 50 mm.
[0079] As an optional option, the value range of L4 is 10 mm to 50 mm, 20 mm to 40 mm, and 25 mm to 35 mm.
[0080] As a preferred solution, the value range of L4 is 20 mm to 25 mm, and the specific value of L4 is 22.4 mm.
[0081] In addition, the dimension L6 of the exit interface of the unit lens in the first direction ranges from 0.2 mm to 3 mm.
[0082] As an optional option, the value range of L6 is 0.2 mm to 0.5 mm, 0.55 mm to 1.0 mm, 1.05 mm to 1.5 mm, and 1.6 mm to 3 mm.
[0083] As an optional option, the value range of L6 is 0.25 mm to 2.8 mm, 0.3 mm to 2 mm, and 0.35 mm to 1.5 mm.
[0084] As a preferred solution, the value range of L6 is 0.25 mm to 0.37 mm, and the specific value of L4 is 0.3 mm.
[0085] As an optional scheme, the radius of curvature of the cylindrical surface of the unit lens ranges from 1 mm to 10 mm; as a further optional scheme, the radius of curvature of the unit lens ranges from 1 mm to 2 mm, 2.1 mm to 3.5 mm, 3.7 mm to 5 mm, 5.5 mm to 7 mm, 7.5 mm to 8 mm, and 8.5 mm to 10 mm.
[0086] As an optional solution, the radius of curvature of the unit lens ranges from 1 mm to 9 mm, 2 mm to 8 mm, 3 mm to 7 mm, 4 mm to 6 mm, or 5 mm to 5.5 mm.
[0087] As a preferred solution, the curvature radius of the exit interface of the unit lens (ie, the first type of exit interface) ranges from 1.1 mm to 1.8 mm, and the curvature radius of the unit lens is more specifically 1.6 mm.
[0088] As an optional scheme, the radius of curvature of the exit interface of the converging lens (i.e., the second type of exit interface) ranges from 5 mm to 100 mm; as a further optional scheme, the radius of curvature of the converging lens ranges from 5 mm to 15 mm, 16 mm to 24 mm, 25 mm to 40 mm, 41 mm to 55 mm, 56 mm to 70 mm, 71 mm to 80 mm, and 80 mm to 100 mm.
[0089] As a limited solution, the radius of curvature of the cylindrical surface of the converging lens ranges from 7 mm to 20 mm, 9 mm to 15 mm, 10 mm to 14 mm, 11 mm to 13.5 mm, and 12.5 mm to 13.2 mm; the specific value of the radius of curvature of the cylindrical surface of the converging lens is 13 mm.
[0090] The function of the converging lens is to make the laser light converge and converge to a certain extent, and at the same time, the converging lens makes the laser light emission angle gradually change. The converging and convergence formed here is mainly because the cylindrical interface at the edge of the converging lens makes the laser light at the edge of the laser light set emitted by the converging lens tilt towards the center at different angles, thus producing the converging and convergence effect.
[0091] So in, for example Figure 5 The laser light indicated by the middle arrow will be projected onto the curved object in a more vertical manner. Moreover, the laser light is evenly irradiated on the surface of the object. For the curved object, the optical paths of multiple laser lights are superimposed, and each projection point can be irradiated by laser lights at different angles, thereby solving the above-mentioned technical problems.
[0092] like Figure 7 As shown, as a preferred solution, the first optical device in this solution still adopts the technical solution introduced above, and the difference of this solution is that the second type of exit interface of the second optical device is composed of an exit plane in the central part and exit arc surfaces on both sides thereof, and the exit plane is different from the above solution. The exit plane is a plane parallel to the first direction. When the area is arc-shaped relative to the area, the plane solution can reduce the divergence of the laser light, so that within the preset detection area, the laser line passing through the exit plane can intersect more with the laser line passing through the exit arc surfaces on both sides in the arc surface area to be detected.
[0093] like Figure 8 As shown in the second preferred solution, the first optical device in this solution still adopts the technical solution introduced above, and the difference is that the second optical device, compared with Figure 7 The scheme shown, Figure 8 The second optical device in the solution shown can be composed of multiple optical elements. Specifically, the original whole lens can be replaced by a central lens and edge lenses on both sides. This has the advantage of facilitating the production and processing of parts.
[0094] like Fig. 9 As shown in the third preferred solution, the first optical device in this solution still adopts the technical solution introduced above, and the difference is that the second optical device, compared with Figure 7 The scheme shown, Fig. 9 The second type of exit interface of the second optical device in the scheme shown is composed of an exit plane and exit inclined planes on both sides. The exit inclined plane is a plane that intersects the first direction left and right. Figure 7The curved exit surface of the middle exit arc surface and the plane of the exit inclined surface are firstly easy to process, and secondly, because the first optical device has a certain arc angle, the deflection of the inclined exit plane is more regular than that of the arc plane laser line, which is convenient for establishing an algorithm model. Of course, the exit arc surfaces on both sides are more conducive to eliminating speckles and adapting to more irregular arc detection surfaces.
[0095] like Fig.10 As shown in the fourth preferred solution, the first optical device in this solution still adopts the technical solution introduced above, and the second type of exit interface of the second optical device in this solution still adopts the solution introduced above, the difference is that the second type of incident interface of the second type of optical device adopts a curved surface convex toward the first optical device, and of course, it can also adopt a similar Fig. 9 The second type of exit interface shown is composed of Fig.10 The second type of incident interface in the illustrated solution, of course, protrudes in the opposite direction. The use of the second type of optical device protruding toward the first optical device can make the central and side light overlap more in the preset detection area.
[0096] Fig. 9 and Fig.10 The scheme shown can also be adopted such as Figure 8 The split scheme shown.
[0097] As another aspect of this application, Fig.11 As shown, the present application also provides a surface detection method based on a three-dimensional laser camera, which can be implemented by the hardware device introduced above.
[0098] Specifically, the method comprises the following steps:
[0099] Make the laser light generated by a laser source emit in parallel along a first direction;
[0100] Make the parallel emitted laser light incident on a plurality of first-type emission interfaces so that the laser light passing through the plurality of the first emission interfaces intersects at a plurality of internal light intersection points respectively;
[0101] The laser light passing through the internal light intersection is incident on a second type of exit interface so that the laser light located at the edge is tilted toward the center and a plurality of laser light intersections are generated on the second type of exit interface;
[0102] Projecting the laser light passing through the second type of exit interface onto the curved surface to be measured;
[0103] The laser light reflected by the curved surface to be measured is made incident on an image sensor.
[0104] The image sensor detects the corresponding three-dimensional shape or size through the shape of the laser surface formed by the laser light in the captured image. This principle is the general principle of a three-dimensional laser camera and is not elaborated here. The method of the present application solves the problem of insufficient reflected light (for a contour point of the surface to be measured) by forming multiple normal direction laser lights on the surface to be measured and intersecting multiple laser lights at one point. At the same time, this method will not cause interference when the contour point of the same surface to be measured is reflected to the image sensor due to different distances, thereby effectively solving the interference problem mentioned earlier.
[0105] As a specific solution, the first type of exit interface at least includes a curved surface convex to the optical exit direction of the laser. The second type of exit interface at least includes a curved surface convex to the optical exit direction of the laser. The first type of exit interface is formed on a cylindrical mirror. The second type of exit interface is formed on another cylindrical mirror.
[0106] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.
Claims
1. A surface detection method based on a three-dimensional laser camera, the method is implemented by a three-dimensional laser camera, and is characterized by: The curved surface detection method based on a three-dimensional laser camera comprises the following steps: making a laser light generated by a laser source emit in parallel along a first direction; Make the parallel emitted laser light incident on a plurality of first-type emission interfaces so that the laser light passing through the plurality of the first-type emission interfaces intersects at a plurality of internal light intersection points respectively; The laser light passing through the internal light intersection is incident on a second type of exit interface so that the laser light located at the edge is tilted toward the center and a plurality of laser light intersections are generated on the second type of exit interface; The first type of exit interfaces are repeatedly arranged in a second direction perpendicular to the first direction; In the second direction, the first type of exit interfaces are all located within the range of the second type of exit interfaces; The radius of curvature of the first type of exit interface is less than or equal to the radius of curvature of the second type of exit interface; The first type of exit interface at least comprises a curved surface convex toward the optical exit direction of the laser; The second type of exit interface at least comprises a curved surface convex toward the optical exit direction of the laser; The first type of exit interface is formed on a cylindrical mirror; The second type of exit interface is formed on another cylindrical mirror; The curved surface detection method based on a three-dimensional laser camera further includes the following steps: projecting the laser light passing through the second type of exit interface onto the curved surface to be measured; The curved surface detection method based on a three-dimensional laser camera also includes the following steps: allowing the laser light reflected by the curved surface to be detected to be incident on an image sensor.
Citation Information
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Apparatus for generating a homogeneous angular distribution of laser irradiation
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