Laser radar

Abstract

The utility model discloses a laser radar which comprises a laser emitter, a laser receiver and a light path arrangement assembly, the laser emitter is used for emitting laser rays for detection, and the laser receiver is used for receiving laser rays returned by detection. The light path arrangement assembly comprises a first light path arrangement element and a second light path arrangement element which are arranged up and down; the first light path arrangement element is used for guiding laser light returned by detection to the second light path arrangement element located below the first light path arrangement element; the second light path arrangement element comprises a total internal reflection part and a light extraction part, the total internal reflection part is used for guiding the laser light to the light extraction part through total internal reflection, and the light extraction part is used for extracting the laser light to be received by the laser receiver, so that a focusing convex lens in the prior art can be replaced; therefore, the limitation on the laser acquisition area of the laser radar is eliminated.

Description

Technical Field

[0001] The utility model relates to the technical field of laser radars, in particular to a laser radar. Background Art

[0002] LiDAR is a device that can measure distance by emitting laser light to the surface of the object and receiving the laser light reflected from the surface of the object.

[0003] Existing laser radars often use focusing convex lenses as optical elements for receiving light paths. However, due to the outer diameter and thickness limitations of the focusing convex lenses, the laser collection area of ​​existing laser radars cannot be too large.

[0004] In addition, the existing focusing convex lens, as an optical element of the receiving light path, will also direct stray light such as light signals from the external environment to the focusing convex lens through the shell gap of the laser radar and the various reflective interfaces inside it. The stray light will be focused by the focusing convex lens and mixed into the laser detection light containing the detection object signal, and finally all will be received by the laser receiver of the laser radar. Therefore, the focusing convex lens has a focusing effect on light signals of different wavelengths during the focusing process, which makes it impossible for the laser radar to eliminate interference from external ambient light, which is not conducive to the accuracy of laser ranging. Utility Model Content

[0005] To this end, in order to solve the above problems, the present invention provides a laser radar that can replace the focusing convex lens in the prior art to remove the limitation on the laser collection area of ​​the laser radar.

[0006] To achieve the above purpose, the technical solutions provided by the present invention are as follows:

[0007] The utility model provides a laser radar, including a laser transmitter, a laser receiver and an optical path arrangement component, wherein the laser transmitter is used to transmit laser light for detection, the laser receiver is used to receive the laser light returned by detection, and the optical path arrangement component includes a first optical path arrangement element and a second optical path arrangement element arranged upper and lower; the first optical path arrangement element is used to guide the laser light returned by detection to the second optical path arrangement element located below it; the second optical path arrangement element includes a total internal reflection part and a light collection part, the total internal reflection part is used to guide the laser light to the light collection part by total internal reflection, and the light collection part is used to collect the laser light for reception by the laser receiver.

[0008] Furthermore, the incident angle of the laser light guided into the second optical path arranging element is θ, and the total internal reflection portion includes a first surface and a second surface spaced apart above and below, and a light-transmitting medium located between the first surface and the second surface. The refractive index n of the light-transmitting medium is configured as follows: the light guided into the second optical path arranging element containing the detection return laser light can allow the detection return laser light to be totally internally emitted on the first surface and the second surface at the incident angle θ, while some light that does not contain the detection return light signal cannot be totally internally emitted on the first surface and the second surface, so as to form an optical filtering channel; the detection return laser light is reflected and folded back by the first surface and the second surface, so as to finally be guided to the light-collecting portion, thereby forming a spectroscopic screening setting.

[0009] Furthermore, the spectrum band of the laser light emitted by the laser transmitter is F, and the photosensitive surface position of the laser receiver is further configured as follows: the photosensitive surface position of the laser receiver is set at a fixed point, and the light-collecting portion has a light-collecting surface for focusing the laser light with the spectrum band F on the photosensitive surface of the laser receiver, so as to ensure that the light with other spectrum bands smaller than F cannot reach the photosensitive surface position of the laser receiver, so that the light guided into the second optical path arranging element, including the detection return laser light, undergoes full internal emission of laser light on the first surface and the second surface, and only the laser light with the spectrum band F can reach the photosensitive surface of the laser receiver at the incident angle θ, so as to form a narrower optical filtering channel.

[0010] Furthermore, the second optical path arranging element is provided with a plurality of equally spaced protrusions and a straight section between two adjacent protrusions on the first surface facing the first optical path arranging element; the upper surface of the protrusion is a refractive surface, so that the light refracted into the refractive surface is reflected multiple times on the second surface and the straight section, so as to increase the displacement deviation of the incident point formed by the light of different spectrum bands on the light-collecting surface of the light-collecting part, and then adjust the emission direction of the light on the light-collecting surface toward the laser receiver, and finally ensure that only the laser light of the spectrum band F can reach the photosensitive surface of the laser receiver at the incident angle θ; the first surface is the light incident surface of the second optical path arranging element.

[0011] Furthermore, the refractive surface is tilted to ensure that the incident angle θ of the laser light in spectrum segment F guided into the second optical path sorting element is not less than the critical angle of total internal reflection, and at the same time, an adjustment setting is formed for the incident angle θ of the laser light in spectrum segment F.

[0012] Furthermore, the inclination angle of the refractive surface is 5 degrees, the length of the straight section is 0.5 mm, and the distance between two adjacent straight sections is 0.5 mm.

[0013] Furthermore, the light collecting portion is arranged in the middle of the bottom of the second optical path arranging element away from the first optical path arranging element, so as to reflect the detected returned laser light upward to the laser receiver located above the second optical path arranging element.

[0014] Furthermore, the light extraction surface of the light extraction portion facing the laser emitter is set as a reflective surface, the reflective surface is a parabola, and the parabola of the second optical path arranging element satisfies the following conditional formula: 2 =16*X, where Y is the height of a point on the parabola of the second light path arranging element, and X is the length of the point on the parabola of the second light path arranging element.

[0015] Furthermore, the first optical path arranging element has a light input surface and a light output surface that are opposite to each other, the light input surface is provided with a plurality of light-focusing structures, the light output surface has a plurality of light-transmitting structures corresponding one to one with the light-focusing structures, the light-transmitting structures have matching reflective surfaces and light-transmitting surfaces, the light-focusing structure is used to refract and focus the laser light returned by the detection onto the reflective surface of the light-transmitting structure corresponding thereto, and then after being reflected by the reflective surface, it is emitted from the first optical path arranging element through the light-transmitting surface, so as to form a focusing and guiding arrangement for the laser light returned by the detection; the light-transmitting surface corresponds to the refractive surface.

[0016] Furthermore, the light-concentrating structure includes ridges, and an upward side of the ridge is configured as an arc surface, and a plurality of arc surfaces are connected end to end to form the light-incoming surface.

[0017] Furthermore, the light-transmitting structure includes a convex tooth, and the side of the convex tooth corresponding to the focusing structure is a reflective surface; the reflective surface is a parabola, and the focus of the parabola of the convex tooth and the arc surface of the convex edge coincides; the side of the convex tooth away from the reflective surface is the light-transmitting surface.

[0018] Furthermore, the radius of the arc surface is 2.54 mm, and the arc width is 1 mm; the paraboloid of the convex tooth satisfies the following conditional formula: 2 =2*X, where Y is the height of a point on the parabola of the convex tooth, and X is the length of the point on the parabola of the convex tooth.

[0019] Furthermore, a filter for filtering out stray light is provided between the laser receiver and the second optical path arranging element.

[0020] Furthermore, it also includes a rotatable reflector; the reflector, the laser transmitter, the laser receiver and the optical path sorting component are coaxially arranged; the reflector is used to reflect the laser light emitted by the laser transmitter to the detection object and reflect the laser light returned by the detection to the laser radar.

[0021] Furthermore, it also includes a circuit board, and a mounting hole for accommodating the circuit board is opened in the center of the first optical path arrangement element, and the laser transmitter and the laser receiver are respectively arranged on the upper and lower surfaces of the circuit board to form an electrical connection; the circuit board is installed in the mounting hole.

[0022] Furthermore, a collimating lens assembly is provided between the reflector and the laser emitter for collimating the laser light emitted by the laser emitter.

[0023] The technical solution provided by the utility model has the following beneficial effects:

[0024] The laser light returned by the detection is guided to the second optical path arranging element located below it through the first optical path arranging element, and the total internal reflection part of the second optical path arranging element guides the laser light to the light collecting part through total internal reflection, and the light collecting part of the second optical path arranging element collects the laser light for receipt by the laser receiver, so as to realize the use of the optical path arranging component of the present invention to replace the focusing convex lens of the prior art, so as to avoid the size limitation of the focusing convex lens of the prior art, and thus remove the limitation on the laser collection area of ​​the laser radar, so as to ensure a wide light signal receiving area. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 The figure shows a schematic diagram of the optical path of the laser radar in the first embodiment;

[0026] Figure 2 FIG. 1 is a schematic diagram of a local optical path of the laser radar in Example 1;

[0027] Figure 3 Shown Figure 2 Enlarged schematic diagram of area A in the middle;

[0028] Figure 4 FIG. 1 is a schematic diagram of a light concentrating element in the first embodiment;

[0029] Figure 5 FIG2 is a schematic diagram of the light guide member in the first embodiment;

[0030] Figure 6 Shown Figure 5 Enlarged schematic diagram of area B in the middle;

[0031] Figure 7 Schematic diagram of the optical paths of stray light and laser light in spectrum band F in Example 1;

[0032] Figure 8 The figure shows a schematic diagram of the optical path of the laser radar in the second embodiment. DETAILED DESCRIPTION

[0033] To further illustrate various embodiments, the present invention is provided with accompanying drawings. These drawings form part of the disclosure of this invention and are primarily used to illustrate the embodiments and, in conjunction with the relevant description in the specification, to explain the operating principles of the embodiments. By referring to these drawings, those skilled in the art will understand other possible implementations and the advantages of this invention. The components in the figures are not drawn to scale, and similar reference numerals are generally used to represent similar components.

[0034] The present invention will now be further described with reference to the accompanying drawings and specific implementation methods.

[0035] Example 1

[0036] Reference Figures 1 to 3 As shown, embodiment 1 provides a laser radar, including a rotatable reflector 3, a laser emitter 4, a laser receiver 5 and an optical path sorting component, wherein the laser emitter 4 is used to emit laser light, the reflector 3 is used to reflect the laser light emitted by the laser emitter 4 to the detection object and reflect the laser light returned by the detection to the optical path sorting component, and the laser receiver 5 is used to receive the laser light derived from the optical path sorting component.

[0037] The optical path arrangement component includes a first optical path arrangement element 1 and a second optical path arrangement element 2 arranged upper and lower. The first optical path arrangement element 1 is used to guide the detected returned laser light to the light incident surface 21 of the second optical path arrangement element 2 located below it. The second optical path arrangement element 2 includes a total internal reflection part and a light extraction part. The total internal reflection part is used to guide the laser light to the light extraction part through total internal reflection, and the light extraction part is used to extract the laser light for reception by the laser receiver 5.

[0038] In this embodiment, the first light path arranging element 1 and the second light path arranging element 2 are both light-transmitting optical elements similar to light guide plates.

[0039] The laser light returned by the detection is guided to the second optical path arranging element 2 located below it through the first optical path arranging element 1, and the total internal reflection part of the second optical path arranging element 2 guides the laser light to the light collecting part through total internal reflection, and the light collecting part of the second optical path arranging element 2 collects the laser light for reception by the laser receiver 5, so as to realize the use of the optical path arranging component of this embodiment to replace the focusing convex lens of the prior art, so as to avoid the size limitation of the focusing convex lens of the prior art, and thus remove the limitation on the laser collection area of ​​the laser radar, so as to ensure a wide light signal receiving area, such as by expanding the outer diameters of the first optical path arranging element 1 and the second optical path arranging element 2 to increase the light receiving area of ​​the laser radar.

[0040] In another preferred embodiment, a surface of the light-collecting portion facing the laser emitter 4 is set as a reflecting surface 22, which is also the light-collecting surface of the light-collecting portion. The reflecting surface 22 is a parabola, that is, the reflecting surface 22 is located at the bottom of the second optical path arranging element 2 away from the first optical path arranging element 1, and a coated reflecting surface is formed by coating the reflecting surface 22 to reflect the laser light to the laser receiver 5 located above the second optical path arranging element 2 to form an upward reverse reflection receiving light path.

[0041] In this specific embodiment, the total internal reflection portion includes a first surface and a second surface spaced apart in an upper and lower manner, and a light-transmitting medium located between the first surface and the second surface. At this time, the second surface and the reflective surface 22 of the light-collecting portion are both on the bottom side of the second optical path sorting element 2, and the incident angle of the laser light guided into the second optical path sorting element 2 is defined as θ. The refractive index of the light-transmitting medium is n, and the refractive index n of the light-transmitting medium is configured so that the light guided into the second optical path sorting element 2 containing the detection return laser light can allow the detection return laser light to be totally internally emitted on the first surface and the second surface at the incident angle θ, while some light that does not contain the detection return light signal cannot be totally internally emitted on the first surface and the second surface to form an optical filtering channel. Therefore, the detection return laser light is reflected and folded back by the first surface and the second surface to finally be guided to the light-collecting portion, thereby forming a spectroscopic screening setting.

[0042] The spectrum segment F of the laser light emitted by the laser emitter 4 of this embodiment adopts a spectrum segment with 905nm as the center wavelength. At this time, part of the light that does not contain the detection return light signal includes stray light with a wavelength greater than the spectrum segment F, and the refractive index n of the second optical path arranging element 2 is 1.581, so as to ensure that the spectrum segment F of the laser light emitted by the laser emitter 4 matches the refractive index n of the second optical path arranging element 2, so as to achieve at least one reflection and refraction of the stray light with a wavelength greater than the spectrum segment F in the optical filtering channel of the second optical path arranging element 2, and part of the light intensity will be lost during the reflection and refraction, and the laser light containing the detection object signal will be totally internally reflected in the optical filtering channel of the second optical path arranging element 2 until it reaches the reflection surface 22 of the second optical path arranging element 2, thereby realizing spectroscopic screening to reduce the optical signal interference of the stray light.

[0043] More preferably, Figure 5 and Figure 6As shown, the first surface of the second optical path arranging element 2, facing the first optical path arranging element 1, is provided with a plurality of equally spaced protrusions 211 and a straight section 213 located between two adjacent protrusions 211. The upper surface of the protrusion 211 serves as a refractive surface 212. This causes the detection return laser light refracted into the refractive surface 212 to undergo multiple rounds of total internal reflection on the second surface and the straight section 213. This increases the displacement deviation of the incident points formed by light of different spectral bands on the reflective surface 22 of the light extraction portion, thereby adjusting the direction of light incident on the reflective surface 22 toward the laser receiver 5, ultimately ensuring that only laser light in spectral band F reaches the photosensitive surface of the laser receiver 5 at an incident angle θ. In this case, the first surface is the light incident surface 21 of the second optical path arranging element 2.

[0044] The refractive surface 212 is tilted to ensure that the incident angle θ of the laser light guided into the second optical path arrangement element 2 is not less than the critical angle of total internal reflection, and at the same time, the incident angle θ of the laser light in the spectrum band F is adjusted.

[0045] Moreover, the parabola of the second optical path arrangement element 2 satisfies the following conditional formula: 2 =16*X, where Y is the height of a point on the parabola of the second optical path arranging element 2, and X is the length of the point on the parabola of the second optical path arranging element 2, so as to reflect the laser light upward in a focused manner to the photosensitive surface of the laser receiver 5 located at the focal point.

[0046] More preferably, Figure 6 As shown, the specific inclination angle β of the refractive surface 212 is 5 degrees, the length of the straight section 213 is 0.5 mm, and the distance between two adjacent straight sections 213 is 0.5 mm, so as to ensure that the incident angle θ of the detected returned laser light refracted into the second optical path sorting element 2 is not less than the critical angle of total internal reflection, so as to achieve total internal reflection in the optical filter channel of the second optical path sorting element 2, so as to ensure that the light intensity loss of the detected returned laser light in the optical filter channel of the second optical path sorting element 2 is within a controllable range, thereby ensuring that there is sufficient light signal to reach the laser receiver 5, and at the same time, the position of the incident point formed by the light with a wavelength smaller than the spectrum band F after passing through the optical filter channel of the second optical path sorting element 2 on the reflecting surface 22 is greatly offset from the position of the incident point formed by the laser light of the spectrum band F on the reflecting surface 22, and ultimately ensure that only the laser light of the spectrum band F can reach the photosensitive surface of the laser receiver 5 at the incident angle θ.

[0047] Through the close cooperation of the protrusion 211, the straight section 213, the second surface and the light-transmitting medium of the second optical path arranging element 2, stray light with a wavelength smaller than the spectrum band F is eliminated, so that the light guided into the second optical path arranging element 2 including the detection return laser light can only allow the laser light of the spectrum band F to be fully internally emitted on the first surface and the second surface at the incident angle θ, so as to form a narrower optical filtering channel, and finally achieve the goal that the light on both sides of the spectrum band F cannot reach the photosensitive surface of the laser receiver 5.

[0048] More preferably, Figure 4 As shown, the first optical path arranging element 1 has a light input surface 11 and a light output surface 12 that are opposite to each other, the light input surface 11 is provided with a plurality of focusing structures, the light output surface 12 has a plurality of light-transmitting structures corresponding to the light-focusing structures, the light-transmitting structures have a matching reflecting surface 122 and a light-transmitting surface 123, the focusing structure is used to refract the detected laser light returned to the reflecting surface 122 of the light-transmitting structure corresponding thereto, and then reflect from the reflecting surface 122 and then emit from the first optical path arranging element 1 through the light-transmitting surface 123, and the light-transmitting surface 123 corresponds to the refractive surface 212.

[0049] The light-concentrating structure includes ridges 111 , and the upwardly facing surfaces of the ridges 111 are configured as arc surfaces 112 . A plurality of arc surfaces 112 are connected end to end to form a light-incoming surface 11 .

[0050] like Figure 3 and Figure 4 As shown, the light-transmitting structure includes a protruding tooth 121. The side of the protruding tooth 121 corresponding to the light-concentrating structure is a reflective surface 122. The reflective surface 122 is a parabola, and the focus of the parabola of the protruding tooth 121 coincides with the focus of the arc surface 112 of the ridge 111. The side of the protruding tooth 121 facing away from the reflective surface 122 is a light-transmitting surface 123. Of course, the vertex of the protruding tooth 121 facing the second light path arranging element 2 can abut the second light path arranging element 2, or it can be arranged above the second light path arranging element 2 with a gap.

[0051] In a specific implementation, the radius of the arc surface 112 of the ridge 111 of the first optical path arranging element 1 is 2.54 mm, the arc width of the ridge 111 is 1 mm, and the paraboloid of the ridge 121 of the first optical path arranging element 1 satisfies the following conditional formula: 2 =2*X, where Y is the height of a point on the parabola of the convex tooth 121 , and X is the length of the point on the parabola of the convex tooth 121 .

[0052] The coordination between the radius of the arc surface 112 and the parabolic surface shape of the convex tooth 121 ensures that light can be focused in the first optical path arranging element 1 and concentrated on the second optical path arranging element 2. At the same time, it plays a role in splitting the light of each wavelength passing through the first optical path arranging element 1 to further increase the incident angle of each wavelength of light in the second optical path arranging element 2.

[0053] More preferably, Figure 7 As shown, a filter 8 for filtering out stray light is provided between the laser receiver 5 and the second optical path arrangement element 2 to further strengthen the screening of optical signals of different wavelengths, so as to further ensure that the laser receiver 5 only receives the laser light signal returned by the detection with a wavelength in the spectrum band F.

[0054] In addition, the reflector 3, laser transmitter 4, laser receiver 5 and the optical path arrangement component are coaxially arranged, and the reflector 3 can rotate around their respective common central axes to ensure that the laser radar performs multi-directional ranging of the detected object within a 360-degree range.

[0055] When the laser radar is working, the laser emitter 4 emits a laser beam upward, which is then reflected by the reflector 3 to the surrounding detection object, and then reflected back to the reflector 3 by the detection object, and then the detected laser beam is reflected downward to the surface of the ridge 111 on the light incident surface 11 of the first optical path arranging element 1. Because the surface of the ridge 111 is a circular arc surface 112, the laser beams directly incident on different positions on the surface of the ridge 111 can be focused first, and then separated and respectively emitted downward to the reflective surface 122 of the light-transmitting structure, and then reflected by the reflective surface 122 to the light-transmitting surface 123, and finally emitted from the light-transmitting surface 123 of the first optical path arranging element 1 until it is refracted into the protrusion 211 on the light incident surface 21 of the second optical path arranging element 2, so as to form a gathering and guiding setting for the detected laser beams.

[0056] When the laser light is refracted into the refractive surface 212 of the protrusion 211 of the second optical path arranging element 2, the refractive surface 212 is preset in a certain inclination angle range so that the incident angle θ of the laser light refracted into the second optical path arranging element 2 is not less than the critical angle of total internal reflection, so that the laser light is totally internally reflected in the optical filter channel of the second optical path arranging element 2, and after multiple total internal reflections, it is emitted to the reflective surface 22 of the second optical path arranging element 2, and then the reflective surface 22 focuses the laser light onto the photosensitive surface of the laser receiver 5, so as to receive the laser light containing the detection object signal.

[0057] By matching the refractive index n of the second optical path arranging element 2 with the wavelength of the laser light, it is ensured that the incident angle θ of the laser light when refracted into the second optical path arranging element 2 is not less than the critical angle of total internal reflection, and at the same time, the stray light with a wavelength greater than the spectrum band F is continuously split, screened and removed during the reflection and refraction in the second optical path arranging element 2. Figure 7 As shown, the emission direction of the stray light with a wavelength smaller than the spectrum band F emitted from the second optical path sorting element 2 cannot be aligned with the photosensitive surface of the laser receiver 5, nor can it be emitted to the photosensitive surface of the laser receiver 5, and finally the laser light of the spectrum band F screened out by the spectral screening is totally internally reflected, and then the reflecting surface 22 of the second optical path sorting element 2 reflects the totally internally reflected laser light of the spectrum band F to the laser receiver 5, so as to eliminate the interference of external ambient light. Compared with the optical path structure composed of the focusing convex lens in the prior art, the optical path sorting component of this embodiment has better laser ranging accuracy and strong anti-interference ability.

[0058] In addition, by setting the reflecting surface 22 in the middle of the bottom of the second optical path sorting element 2, a receiving light path that is reflected upward and focused is formed. In this way, miniaturization in size (such as thickness, etc.) can be achieved due to the lack of focal length limitations of the focusing convex lens.

[0059] In another preferred embodiment, Figure 1 and Figure 2 As shown, the laser radar of this embodiment also includes a circuit board 6. The first optical path arrangement element 1 is provided with a mounting hole for accommodating the circuit board 6. The laser emitter 4 and the laser receiver 5 are respectively arranged on the upper and lower surfaces of the circuit board 6 to form an electrical connection. The circuit board 6 is installed in the mounting hole.

[0060] By arranging the laser emitter 4 and the laser receiver 5 on the upper and lower surfaces of the circuit board 6 respectively and forming electrical connection settings respectively, the integration of the circuit board and electronic components is realized, and the space utilization is improved. The structure is simpler and more compact, and the installation is convenient. In addition, signal acquisition is simpler and faster, that is, direct wired power supply for functional components such as the laser emitter 4 and the laser receiver 5 is achieved under the premise of only one circuit board 6, thereby improving the stability of the signal transmission and power supply system.

[0061] Further preferably, a collimating lens assembly 7 is provided between the reflector 3 and the laser emitter 4 for collimating the laser light emitted by the laser emitter 4 .

[0062] Example 2

[0063] like Figure 8As shown, embodiment 2 provides a laser radar. The structure of embodiment 2 is substantially the same as that of embodiment 1, except that: the reflecting surface of the second optical path arranging element 2 is arranged above the second optical path arranging element 2 facing the first optical path arranging element 1, so as to reflect the detected laser light returned to the laser receiver 5 located below the second optical path arranging element 2, so as to form a downward-focused receiving optical path. More specifically, the laser receiver 5 is arranged at the focal point below the second optical path arranging element 2, and the laser emitter 4 and the circuit board 6' are integrated into one through electrical connection, and a coaxial laser ranging system is formed by the reflector 3, the collimating lens assembly 7, the laser emitter 4, the circuit board 6', the first optical path arranging element 1, the second optical path arranging element 2 and the laser receiver 5 to realize the spectroscopic screening of the detection light to eliminate the interference of external ambient light, thereby ensuring better laser ranging accuracy.

[0064] Example 3

[0065] Embodiment 3 provides a laser radar. The structure of embodiment 3 is substantially the same as that of embodiment 1, except that: the reflector is stationary, and the reflecting surface of the second optical path arranging element is a mirror reflecting surface of a planar structure, so that the laser light detected by total internal reflection can also be reflected by mirror reflection to the photosensitive surface of the laser receiver.

[0066] Although the present invention has been specifically shown and described in conjunction with the preferred embodiments, those skilled in the art should understand that various changes can be made to the form and details of the present invention without departing from the spirit and scope of the present invention as defined by the appended claims, and all of these changes are within the scope of protection of the present invention.

Claims

1. A laser radar comprising a laser transmitter, a laser receiver, and an optical path arrangement component, wherein the laser transmitter is used to transmit laser light for detection, and the laser receiver is used to receive the laser light returned by detection, characterized in that: The optical path arranging component includes a first optical path arranging element and a second optical path arranging element arranged in an upper and lower manner; The first optical path arranging element is used to guide the detection return laser light to the second optical path arranging element located below it; The second optical path arrangement element includes a total internal reflection portion and a light extraction portion. The total internal reflection portion is used to guide the laser light to the light extraction portion through total internal reflection, and the light extraction portion is used to extract the laser light for reception by the laser receiver.

2. The laser radar according to claim 1, wherein: The incident angle of the laser light guided into the second optical path arranging element is θ, and the total internal reflection portion includes a first surface and a second surface spaced apart above and below, and a light-transmitting medium located between the first surface and the second surface. The refractive index n of the light-transmitting medium is configured as follows: the light guided into the second optical path arranging element containing the detection return laser light can allow the detection return laser light to be totally internally emitted on the first surface and the second surface at the incident angle θ, while some light that does not contain the detection return light signal cannot be totally internally emitted on the first surface and the second surface, so as to form an optical filtering channel; the detection return laser light is reflected and folded back by the first surface and the second surface, so as to finally be guided to the light-collecting portion, thereby forming a spectroscopic screening setting.

3. The laser radar according to claim 2, wherein: The spectrum band of the laser light emitted by the laser transmitter is F, and the photosensitive surface position of the laser receiver is further configured as follows: the photosensitive surface position of the laser receiver is set at a fixed point, and the light-collecting portion has a light-collecting surface for focusing the laser light with the spectrum band F on the photosensitive surface of the laser receiver, so as to ensure that the light with other spectrum bands smaller than F cannot reach the photosensitive surface position of the laser receiver, so that the light guided into the second optical path arranging element, including the detection return laser light, undergoes full internal emission of laser light on the first surface and the second surface, and only the laser light with the spectrum band F can reach the photosensitive surface of the laser receiver at the incident angle θ, so as to form a narrower optical filtering channel.

4. The laser radar according to claim 3, wherein: The first surface of the second light path arranging element facing the first light path arranging element is provided with a plurality of protrusions arranged at equal intervals and a straight section located between two adjacent protrusions; The upper surface of the protrusion is a refractive surface, so that the light refracted into the refractive surface is reflected multiple times on the second surface and the straight section, so as to increase the displacement deviation of the incident point formed by the light of different spectrum bands on the light-collecting surface of the light-collecting part, and then adjust the emission direction of the light on the light-collecting surface toward the laser receiver, and finally ensure that only the laser light of the spectrum band F can reach the photosensitive surface of the laser receiver at the incident angle θ; the first surface is the light incident surface of the second optical path arrangement element.

5. The laser radar according to claim 4, characterized in that: The refractive surface is tilted to ensure that the incident angle θ of the laser light in spectrum segment F guided into the second optical path sorting element is not less than the critical angle of total internal reflection, and at the same time, an adjustment setting is formed for the incident angle θ of the laser light in spectrum segment F.

6. The laser radar according to claim 5, characterized in that: The inclination angle of the refractive surface is 5 degrees, the length of the straight section is 0.5 mm, and the distance between two adjacent straight sections is 0.5 mm.

7. The laser radar according to any one of claims 4 to 6, characterized in that: The light extraction portion is arranged in the middle of the bottom of the second optical path arranging element away from the first optical path arranging element, so as to reflect the detected returned laser light upward to the laser receiver located above the second optical path arranging element.

8. The laser radar according to claim 7, characterized in that: The light extraction surface of the light extraction portion facing the laser emitter is set as a reflective surface, and the reflective surface is a parabola. The parabola of the second optical path arranging element satisfies the following conditional formula: 2 =16*X, where Y is the height of a point on the parabola of the second light path arranging element, and X is the length of the point on the parabola of the second light path arranging element.

9. The laser radar according to any one of claims 4 to 6, characterized in that: The first optical path arranging element has a light input surface and a light output surface that are opposite to each other, the light input surface is provided with a plurality of light-focusing structures, the light output surface has a plurality of light-transmitting structures corresponding one to one with the light-focusing structures, the light-transmitting structures have matching reflective surfaces and light-transmitting surfaces, the light-focusing structure is used to refract and focus the laser light returned by the detection onto the reflective surface of the light-transmitting structure corresponding thereto, and then reflect from the reflective surface and then emit the first optical path arranging element through the light-transmitting surface, so as to form a focusing and guiding arrangement for the laser light returned by the detection; the light-transmitting surface corresponds to the refractive surface.

10. The laser radar according to claim 9, characterized in that: The light-concentrating structure includes a convex ridge, an upward side of the convex ridge is configured as an arc surface, and a plurality of arc surfaces are connected end to end to form the light-incoming surface.

11. The laser radar according to claim 10, characterized in that: The light-transmitting structure includes a convex tooth, and the side of the convex tooth corresponding to the focusing structure is a reflective surface; the reflective surface is a parabola, and the focus of the parabola of the convex tooth and the arc surface of the convex edge coincide with each other; the side of the convex tooth away from the reflective surface is the light-transmitting surface.

12. The laser radar according to claim 11, characterized in that: The radius of the arc surface is 2.54 mm, and the arc width is 1 mm; the paraboloid of the convex tooth satisfies the following conditional formula: 2 =2*X, where Y is the height of a point on the parabola of the convex tooth, and X is the length of the point on the parabola of the convex tooth.

13. The laser radar according to claim 12, characterized in that: A filter for filtering out stray light is provided between the laser receiver and the second optical path arranging element.

14. The laser radar according to any one of claims 1 to 6, characterized in that: It also includes a rotatable reflector; the reflector, the laser transmitter, the laser receiver and the optical path sorting component are coaxially arranged; the reflector is used to reflect the laser light emitted by the laser transmitter to the detection object and reflect the laser light returned by the detection to the laser radar.

15. The laser radar according to claim 14, characterized in that: It also includes a circuit board, and a mounting hole for accommodating the circuit board is opened at the center of the first optical path arrangement element. The laser emitter and the laser receiver are respectively arranged on the upper and lower surfaces of the circuit board and form an electrical connection arrangement; the circuit board is installed in the mounting hole.

16. The laser radar according to claim 14, characterized in that: A collimating lens assembly is provided between the reflector and the laser emitter for collimating the laser light emitted by the laser emitter.

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