Laser ranging module
By setting the light source and collimating assembly in the laser ranging module to the non-coaxial state, the information loss problem caused by limited field angle in traditional technology is solved, and a higher precision measurement is achieved.
Patent Information
- Application Number
- CN202421599224.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-05
- Publication Date
- 2025-05-30
- Estimated Expiration
- 2034-07-05
AI Technical Summary
When the field angle of the imaging component is limited, it is difficult for traditional linear light sources to fully acquire linear structured light information incident on the target surface, resulting in information loss.
By setting the light source and collimating assembly to an non-coaxial state, the initial beam is converted into a deflected collimating beam, ensuring that the imaging assembly and the center of the spot are located in the same plane, reducing information loss.
Under the finite field of view angle, more complete acquisition of image information at the target surface spot is achieved, improving measurement accuracy and reducing information loss.
Smart Images
Figure CN222926867U_ABST
Abstract
Description
Technical Field
[0001] The embodiments of the present application relate to the field of optical measurement technology, and particularly to a laser ranging module. Background Art
[0002] A line laser light source generally refers to a laser light source that outputs a linear structured light. Line laser modules have a wide range of applications in many fields, such as 3D scanning, industrial measurement and positioning, machine vision, etc. The development of line laser technology has continuously promoted innovation and progress in various fields, providing higher precision, efficiency, and functionality for a variety of applications. Especially in fields that require high precision, fast response, and automated control.
[0003] Traditional line light sources are generally coaxial systems, that is, the center heights of the light source, the imaging component (usually a lens), and the output line-shaped light spot are the same. When the imaging component collects the line-shaped structured light generated by the light source irradiating the target surface, since the imaging component and the light source are not at the same height, the line light spot in the collected image will also deviate from the center position of the image. When the field of view angle of the imaging component is not large enough, some information of the line-shaped structured light will be lost. Summary of the Utility Model
[0004] The embodiments of the present application provide a laser ranging module for completely obtaining the information of the line-shaped structured light incident on the target surface when the field of view angle of the imaging component is limited.
[0005] A laser ranging module provided in the first aspect of the embodiments of the present application includes:
[0006] A light source for emitting an initial beam;
[0007] A collimating component for collimating the initial beam to obtain a collimated beam and guiding the collimated beam to irradiate the target surface to form a light spot, and the optical axis of the collimating component does not coincide with the optical axis of the light source;
[0008] An imaging component for collecting an image at the light spot on the target surface, the connection line between the imaging component and the target surface coincides with the optical axis of the imaging component, and the imaging component and the light source are arranged on the same plane.
[0009] In some specific implementation manners, it further includes:
[0010] A shaping component for shaping the collimated beam to obtain a shaped beam and guiding the shaped beam to reach the target surface to form a light spot in a preset pattern.
[0011] In some specific implementation manners, the optical axis of the shaping component is parallel to the optical axis of the collimated beam.
[0012] In some specific implementation manners, the light spot is a line light spot, the collimating component is further configured to control the line width of the light spot, the shaping component is a cylindrical lens array, and the cylindrical lens array controls the line length of the light spot by controlling the divergence angle of the shaping light beam, and the field of view angle of the imaging component is not less than the divergence angle of the shaping light beam.
[0013] In some specific implementation manners, it further includes: a substrate, and the light source, the collimating component, the shaping component, and the imaging component are fixedly arranged on the substrate.
[0014] In some specific implementation manners, the shaping component includes a cylindrical lens array, a lens, an optical waveguide, a curved mirror, or a prism.
[0015] In some specific implementation manners, the deflection angle θ between the optical axis of the collimated light beam and the optical axis of the initial light beam is equal to where h is the distance between the optical axis of the initial light beam and the optical axis of the collimating component, and f is the focal length of the collimating component.
[0016] In some specific implementation manners, the incident direction of the collimated light beam reaching the shaping component is the same as the outgoing direction of the shaping light beam from the shaping component, and the quotient of the distance H between the light source and the imaging component and the distance L between the imaging component and the target surface is equal to tanθ.
[0017] In some specific implementation manners, the deflection angle between the optical axis of the collimated light beam and the optical axis of the initial light beam is 10° to 30°.
[0018] In some specific implementation manners, the collimating component includes a collimating lens, a metasurface lens, or a surface mirror.
[0019] As can be seen from the above technical solutions, the embodiments of the present application have the following advantages: Since the imaging component and the light source are arranged on the same plane, and the light source and the collimating component are in a non-coaxial state, after being processed by the collimating component, the initial light beam will be transformed into a deflected collimated light. This setting makes the angle between the line connecting the imaging component and the target surface and the optical axis of the initial light beam smaller than the coaxial setting in the prior art. In this way, even when the field of view angle of the imaging component is limited, the imaging component can better obtain the image of the light spot on the target surface, and it is ensured that under the same field of view angle of the imaging component, the information of the structured light formed by the collimated light beam irradiating the target surface can be obtained to the greatest extent, effectively reducing the loss of information. In addition, the above setting method makes the imaging position of the light spot closer to the central field of view of the imaging perspective, which can reduce the influence of off-axis lens aberration and improve the measurement accuracy. Description of the Drawings
[0020] To more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the accompanying drawings required for the description of the embodiments. Obviously, the accompanying drawings in the following description are only some embodiments recorded in the present application. For those of ordinary skill in the art, other accompanying drawings can also be obtained based on these drawings.
[0021] Figure 1 It is a schematic structural diagram of the laser ranging module according to an embodiment of the present application;
[0022] Figure 2 It is another schematic structural diagram of the laser ranging module according to an embodiment of the present application;
[0023] Among them, the reference numerals are:
[0024] 1. Light source; 2. Collimating component; 3. Target surface; 4. Imaging component; 5. Shaping component. Detailed implementation manners
[0025] In order to enable those skilled in the art to better understand the solutions of the present application, the following will clearly and completely describe the technical solutions in the embodiments of the present application in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.
[0026] In the description of the embodiments of the present application, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the embodiments of the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the embodiments of the present application. In addition, the terms "first", "second", "third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.
[0027] In the description of the embodiments of the present application, it should be noted that unless otherwise clearly specified and limited, the terms "installation", "connection", "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to specific situations.
[0028] To better illustrate the accompanying drawings of the present application, the coordinate axes appearing in the accompanying drawings of the present application will be described below. First, the Z-axis in the embodiments of the present application is the optical axis of the collimated beam or the optical axis of the shaped beam; the X-axis direction is parallel to the connection line between the light source 1 and the imaging component 4, that is, when observing the laser ranging module of the present application from the X-axis direction, the light source 1 and the imaging component 4 overlap; furthermore, the Y-axis direction is naturally perpendicular to the connection line between the light source 1 and the imaging component 4 and perpendicular to the Z-axis. The coordinate system including the X-axis and the Z-axis in the figure illustrates the relative positional relationship of each component when observing the laser ranging module of the present application from the plane where the X-axis and the Z-axis are located, or the XZ plane; the coordinate system including the Y-axis and the Z-axis in the figure illustrates the relative positional relationship of each component when observing the laser ranging module of the present application from the plane where the Y-axis and the Z-axis are located, or the YZ plane.
[0029] Next, please refer to Figure 1 , an embodiment of the present application provides a laser ranging module, including:
[0030] A light source 1 for emitting an initial beam;
[0031] A collimating component 2 for collimating the initial beam to obtain a collimated beam and guiding the collimated beam to irradiate the target surface 3 to form a light spot, and the optical axis of the collimating component 2 does not coincide with the optical axis of the light source 1;
[0032] An imaging component 4 for collecting an image at the light spot on the target surface 3, the connection line between the imaging component 4 and the target surface 3 coincides with the optical axis of the imaging component 4, and the imaging component 4 and the light source 1 are arranged on the same plane. Among them, since there is a certain divergence angle in the initial beam emitted by the light source 1, therefore, a collimating component 2 also needs to be provided to ensure the effect of the light spot irradiated on the target surface 3.
[0033] It should be noted that in the incident light path of the prior art solution (that is, the route through which the light source emits and reaches the target surface), the light source and the collimating component in the entire laser ranging module form a coaxial system, that is, the center heights of the light source, the collimating component, and the light spot formed by irradiating the target surface are the same. This leads to the fact that when the receiving component collects the linear structured light generated by this light source on the target surface, the center of the field of view of the imaging component and the laser light source can never be at the same height, that is, the connection line between the two cannot be parallel to the incident light path of the prior art solution. In addition, in the prior art solution, both the light source and the imaging component are fixed on the same substrate, and the emission direction of the light source and the optical axis direction of the imaging component are parallel. Therefore, when the field of view angle of the imaging component is limited, the imaging component usually cannot collect the complete light spot in the image of the target surface at the light spot, and thus part of the structured light information is lost.
[0034] To solve this problem, based on the existing technical solution, the embodiment of the present application conceives to offset the optical axes of the light source 1 and the collimating component 2 on the incident light path (i.e., the route through which the light emitted by the light source 1 reaches the target surface 3). In this way, the central heights of the light source 1, the collimating component 2, and the spot formed by irradiating the target surface 3 are all inconsistent, but the central heights of the imaging component 4 and the spot formed by irradiating the target surface 3 can be kept consistent. This can make the center of the spot located at the center of the field of view angle of the imaging component 4, reduce the interference caused by distortion during the image acquisition process, and ensure that the imaging component 4 can also more completely acquire the spot formed by the shaping beam irradiating the target surface 3 within the limited field of view angle, that is, completely acquire the signal light (or structural light) formed by the shaping beam irradiating the target surface 3, thereby improving the accuracy of distance measurement.
[0035] Among them, the light source 1 in the embodiment of the present application can be any laser light source 1.
[0036] In the embodiment of the present application, since the imaging component 4 and the light source 1 are arranged on the same plane, and the light source 1 and the collimating component 2 are in a non-coaxial state, after being processed by the collimating component 2, the initial beam will be transformed into a deflected collimated light. This setting makes the angle between the line connecting the imaging component 4 and the target surface 3 and the optical axis of the initial beam smaller than that in the coaxial setting of the prior art. In this way, even when the field of view angle of the imaging component 4 is limited, the imaging component 4 can better acquire the image of the spot on the target surface 3, and ensure that under the same field of view angle of the imaging component 4, the information of the structural light formed by the collimated beam irradiating the target surface 3 can be acquired to the greatest extent, effectively reducing the loss of information. In addition, the above setting method makes the imaging position of the spot closer to the central field of view of the imaging perspective, which can reduce the influence of off-axis lens aberration and improve the measurement accuracy.
[0037] In some specific implementation manners, the collimating component 2 described in the embodiments of the present application can be any optical device including but not limited to a collimating lens, a meta-lens, or a surface mirror that can meet the requirements of beam collimation and guide the emitted collimated beam to the target surface 3 or the shaping component 5, and is not limited here.
[0038] It can be understood that in practical applications, the part of the collimation component 2 close to the periphery cannot achieve a good collimation effect. Therefore, in order to improve the utilization rate of the light beam, during use, it is generally ensured that the initial light beam shines on the part of the collimation component 2 where effective collimation can be achieved. Generally, in the above situation, the deflection angle θ between the optical axis of the collimated light beam and the optical axis of the initial light beam is controlled within the range of 10° to 30°. And within the range of 10° to 30°, the optical center of the initial light beam is closer to the optical center of the collimation component 2, effectively ensuring the collimation effect. Specifically, the control of this deflection angle θ can be achieved by adjusting the distance between the light source 1 and the collimation component 2 in the direction perpendicular to the collimation component 2, and the distance between the light source 1 and the collimation component 2 in the direction parallel to the collimation component 2, and no specific limitation is made here.
[0039] In some specific implementation manners, based on the optical principle, it can be known that the deflection angle θ between the optical axis of the collimated light beam and the optical axis of the initial light beam is approximately equal to where h is the distance between the optical axis of the initial light beam and the optical axis of the collimation component 2, and f is the focal length of the collimation component 2. In order to reduce the calculation complexity, the embodiments of the present application define In this way, the embodiments of the present application can accurately calculate the deflection angle θ between the optical axis of the collimated light beam and the optical axis of the initial light beam according to the foregoing formula to achieve the best collimation effect.
[0040] Please refer to Figure 2 The embodiments of the present application provide a laser ranging module similar to the embodiment shown in Figure 1 The difference is that the laser ranging module of the embodiments of the present application further includes: a shaping component 5, configured to perform shaping processing on the collimated light beam to obtain a shaped light beam, and guide the shaped light beam to reach the target surface 3 to form a light spot in a preset pattern.
[0041] Considering the influence of light beams of different shapes on the ranging effect, on the basis of the embodiment shown in Figure 1 the embodiments of the present application further introduce a shaping component 5, configured to guide the shaped light beam to reach the target surface 3 to form a light spot in a preset pattern. The preset pattern may be a rectangular light spot, a square light spot, a line light spot or any other light spot in an arbitrary shape that meets different ranging requirements, and no limitation is made in the embodiments of the present application.
[0042] In some specific implementation manners, if the light spot is a line light spot, the specific collimation component 2 is further configured to control the line width of the light spot, the shaping component 5 is a cylindrical lens array, the cylindrical lens array controls the line length of the light spot by controlling the divergence angle of the shaped light beam, and the field of view angle of the imaging component 4 is not less than the divergence angle of the shaped light beam.
[0043] Specifically, please refer to Figure 2 The divergence angle is as shown in Figure 2The FOV shown in the following figure, i.e., the Field of View. Since the divergence angle of the shaped beam is strongly correlated with the line length of the light spot, simply put, the distance between the divergence angle of the shaped beam, the optical center of the cylindrical lens array, and the center of the light spot irradiated on the target surface 3 determines the line length of the light spot irradiated on the target surface 3. Therefore, in order to ensure that the collected image includes the complete light spot to the greatest extent without losing any structured light information, the field of view angle of the imaging component 4 should not be less than the divergence angle of the shaped beam.
[0044] In some specific embodiments, the shaping component 5 described in the embodiments of the present application may be any optical device including but not limited to a cylindrical lens array, a lens, an optical waveguide, a curved mirror, or a prism that can meet the requirements of beam shaping and guide the emitted shaped beam to the target surface 3, which is not limited here.
[0045] Based on the foregoing embodiments, in order to reduce the complexity of the optical system of the laser ranging module of the present application, the embodiments of the present application may make the shaping component 5, the collimated beam, and the shaped beam coaxial through the adjustment and setting of the shaping component 5. Specifically, the optical axis of the shaping component 5 may be set at a position that coincides with the optical axis of the collimated beam and the optical axis of the shaped beam emitted from the shaping component 5. Among them, it can be in accordance with Figure 2 , in this setting method, if the shaping component 5 is parallel to the deflected collimated beam, that is, the shaping component 5 rotates along the rotation axis perpendicular to the X-axis, there is a deflection of the construction angle θ between the shaping component 5 and the connection line between the imaging component 4 and the target surface 3.
[0046] Furthermore, in some specific implementation manners, if the optical axes of the shaping component 5, the collimated beam, and the shaped beam are the same, the quotient of the distance H between the light source 1 and the imaging component 4 and the distance L between the imaging component 4 and the target surface 3 should be equal to tanθ, which can strictly ensure that the connection line between the imaging component 4 and the target surface 3 coincides with the optical axis of the imaging component 4. Among them, the connection line between the imaging component 4 and the target surface 3 specifically refers to the connection line between the optical center of the imaging component 4 and the optical center of the light spot formed by irradiating the target surface 3.
[0047] On the basis of the foregoing embodiments, in practical applications, the laser ranging modules described in the embodiments of the present application can be applied to technical fields such as consumer electronic products, home automation and robotics, industrial and robotic applications, medical and health monitoring, and scientific research, and realize the corresponding ranging functions. It can be seen that in order to improve space utilization, each optical device in the laser ranging module can be centrally arranged on a substrate, and the substrate is a plane. Therefore, the light source 1, the collimating component 2, the shaping component 5, and the imaging component 4 can all be fixedly arranged on this plane of the substrate. In addition, the control of the light source 1 and the imaging component 4 can be realized by a circuit arranged on the substrate, and the circuit can be arranged by means of etching or wires, etc., which is not limited in the embodiments of the present application.
[0048] It should be noted that the guiding in each embodiment of the present application can refer to various beam propagation methods such as reflection, refraction, transmission, and scattering that can achieve the corresponding purposes, which are not limited here.
[0049] The above embodiments are only used to illustrate the technical solutions of the present application, rather than limiting them.
Claims
1. A laser ranging module, characterized in that: include: A light source, for emitting an initial light beam; A collimating component, used for collimating the initial light beam to obtain a collimated light beam, and guiding the collimated light beam to irradiate a target surface to form a light spot, wherein the optical axis of the collimating component does not coincide with the optical axis of the light source; An imaging component is used to collect the image at the light spot on the target surface. The line connecting the imaging component and the target surface coincides with the optical axis of the imaging component. The imaging component and the light source are arranged in the same plane.
2. The laser ranging module according to claim 1, characterized in that: Also includes: The shaping component is used to shape the collimated light beam to obtain a shaped light beam, and guide the shaped light beam to reach the target surface to form a light spot in a preset pattern.
3. The laser ranging module according to claim 2, characterized in that: The optical axis of the shaping component is parallel to the optical axis of the collimated light beam.
4. The laser ranging module according to claim 2, characterized in that: The light spot is a linear light spot, the collimating component is also used to control the line width of the light spot, the shaping component is a cylindrical mirror array, and the cylindrical mirror array controls the line length of the light spot by controlling the divergence angle of the shaped light beam, and the field of view angle of the imaging component is not less than the divergence angle of the shaped light beam.
5. The laser ranging module according to claim 2, characterized in that: Also includes: A substrate, the light source, the collimating component, the shaping component and the imaging component are fixedly arranged on the substrate.
6. The laser distance measurement module according to any one of claims 2 to 5, characterized in that: The shaping component includes a cylindrical mirror array, a lens, an optical waveguide, a curved mirror or a prism.
7. The laser ranging module according to any one of claims 2 to 5, characterized in that: The deflection angle θ between the optical axis of the collimated light beam and the optical axis of the initial light beam is equal to Wherein h is the distance between the optical axis of the initial light beam and the optical axis of the collimating component, and f is the focal length of the collimating component.
8. The laser ranging module according to claim 7, characterized in that: The incident direction of the collimated light beam to the shaping component is the same as the exit direction of the shaped light beam from the shaping component, and the quotient of the distance H between the light source and the imaging component and the distance L between the imaging component and the target surface is equal to tanθ.
9. The laser ranging module according to claim 7, characterized in that: The deflection angle between the optical axis of the collimated light beam and the optical axis of the initial light beam is 10° to 30°.
10. The laser ranging module according to claim 1, characterized in that: The collimating component includes a collimating lens, a super lens or a surface-encapsulating reflector.