LiDAR that reduces blind spots

Abstract

The present invention discloses a laser radar capable of reducing blind spots. According to one embodiment of the present invention, the laser radar includes: a transmitting part capable of emitting laser light; a transmitting lens located in the light output path of the transmitting part, having an incident part for the laser light to be incident on the transmitting lens and an exit part for the laser light to be emitted from the transmitting lens, the transmitting lens extending from the incident part to the exit part, and including a first corner part and a second corner part; a receiving part for receiving the laser light reflected by an object outside the laser radar after being emitted from the transmitting part; a receiving lens capable of changing the path of the laser light reflected by the object after being emitted from the transmitting part so that the laser light is irradiated to the receiving part, wherein the laser light is reflected at the first corner part and the second corner part of the transmitting lens, the main axis of the exit part of the transmitting lens and the main axis of the receiving lens are located in the same straight line, and the extending direction of the transmitting lens from the incident part to the first corner part close to the incident part is parallel to the straight line.

Description

Technical Field

[0001] The present invention relates to a laser radar, and in particular to a laser radar capable of reducing blind spots. Background Art

[0002] As a radar device, laser radar has the advantages of high precision, strong anti-interference ability, and fast response speed, so it is suitable for a variety of use environments. As described above, the laser radar can emit a laser beam as a detection signal to the surrounding three-dimensional space, and the laser beam is reflected by the objects in the surrounding space and becomes an echo signal and returns. The laser radar compares the received echo signal with the emitted detection signal to obtain relevant information about the surrounding objects such as distance and speed.

[0003] As described above, the laser radar includes a transmitting unit and a receiving unit. The transmitting unit generates and emits a laser beam, and the laser beam that hits the surrounding objects and is reflected back is received by the receiving unit. Since the speed of light is known, the distance of the surrounding objects relative to the laser radar can be measured by the propagation time of the laser.

[0004] In existing laser radars, the transmitting part and the receiving part are usually arranged laterally and spaced apart, so there may be a blind spot in the area between the transmitting part and the receiving part in front of the transmitting part and the receiving part. This becomes a disadvantage when using laser radar to measure close objects. Therefore, it is necessary to provide a laser radar that can reduce the above-mentioned blind spot. Summary of the invention

[0005] The present invention provides a laser radar capable of reducing blind spots.

[0006] According to an embodiment of the present invention, a laser radar may include: a transmitting unit capable of emitting laser light; a transmitting lens located on a light output path of the transmitting unit, having an incident portion for allowing the laser light to be incident on the transmitting lens and an exit portion for allowing the laser light to be emitted from the transmitting lens, the transmitting lens extending from the incident portion to the exit portion and including a first corner portion and a second corner portion; a receiving unit for receiving the laser light emitted from the transmitting unit and reflected by an object outside the laser radar; a receiving lens capable of changing the path of the laser light emitted from the transmitting unit and reflected by the object to cause the laser light to be irradiated to the receiving unit, wherein the laser light is reflected at the first corner portion and the second corner portion of the transmitting lens, the main axis of the exit portion of the transmitting lens and the main axis of the receiving lens are located on the same straight line, and the extending direction of the transmitting lens from the incident portion to the first corner portion close to the incident portion is parallel to the straight line.

[0007] Furthermore, the receiving unit and the transmitting unit may be disposed on the same substrate.

[0008] Furthermore, after the laser light is totally reflected at the first corner portion, it can be totally reflected at the second corner portion and then emitted from the emission portion.

[0009] Furthermore, the receiving portion may also be located on the straight line.

[0010] Furthermore, the incident portion of the emitting lens may have a convex lens shape.

[0011] According to another embodiment of the present invention, a laser radar may include: a transmitting unit capable of emitting laser light; a receiving unit for receiving laser light emitted from the transmitting unit and reflected by an object outside the laser radar; and an integrated lens having a transmitting lens unit and a receiving lens unit, wherein the transmitting lens unit is located in the light exit path of the transmitting unit and has an incident unit for causing the laser light to enter the transmitting lens unit and an exit unit for causing the laser light to exit from the transmitting lens unit, the transmitting lens unit extends from the incident unit to the exit unit and includes a first corner unit and a second corner unit, the receiving lens unit is capable of changing the path of the laser light emitted from the transmitting unit and reflected by the object so that the laser light is irradiated to the receiving unit, the exit unit of the transmitting lens unit is inserted into a hole located in the receiving lens unit or the exit unit of the transmitting lens unit is closely attached to one side of the receiving lens unit, wherein the laser light is reflected at the first corner unit and the second corner unit of the transmitting lens unit, the main axis of the exit unit of the transmitting lens unit and the main axis of the receiving lens unit are located in the same straight line, and the extending direction of the transmitting lens unit from the incident unit to the first corner unit close to the incident unit is parallel to the straight line.

[0012] Furthermore, the receiving unit and the transmitting unit may be disposed on the same substrate.

[0013] Furthermore, after the laser light is totally reflected at the first corner portion, it can be totally reflected at the second corner portion and then emitted from the emission portion.

[0014] Furthermore, the receiving portion may also be located on the straight line.

[0015] Furthermore, the incident portion of the emission lens portion may have a convex lens shape.

[0016] According to one embodiment of the present invention, a laser radar capable of reducing blind spots can be provided. With the laser radar as described above, the laser emitted by the transmitting unit can be moved in the horizontal direction using a transmitting lens to reduce the blind spot between the transmitting unit and the receiving unit. Furthermore, by integrally forming the transmitting lens, the process required for optical path alignment can be simplified when setting the receiving lens. Furthermore, compared to the case where the transmitting unit is directly arranged in front of the optical path of the receiving unit, the length in the up-down direction can be reduced. Furthermore, the transmitting unit and the receiving unit can be arranged on the same substrate, thereby simplifying the substrate structure. Furthermore, the transmitting lens can be formed longer to increase the degree of collimation of the emitted laser.

[0017] The effects of the present invention are not limited to the effects described above, and those skilled in the art can derive effects not described above from the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a side view showing a laser radar capable of reducing a blind spot according to a first embodiment of the present invention.

[0019] Figure 2 is a perspective view showing a transmitting lens and a receiving lens according to a first embodiment of the present invention.

[0020] Figure 3 is a top view showing a transmitting lens and a receiving lens according to a first embodiment of the present invention.

[0021] Figure 4 is a side view showing a transmitting lens according to a first embodiment of the present invention.

[0022] Figure 5 is a side view showing an integrated lens according to a second embodiment of the present invention.

[0023] Explanation of symbols

[0024] 100: Transmitter 200: Receiver

[0025] 300: Transmitting lens 400: Receiving lens

[0026] 500: Substrate DETAILED DESCRIPTION

[0027] The technical scheme of the embodiment of the present invention will be described in detail below in conjunction with the accompanying drawings of the embodiment of the present invention. Obviously, the embodiments disclosed below are only part of the embodiments of the present invention, rather than all the embodiments. Based on the following embodiments, all other embodiments obtained by ordinary technicians in this field without making creative work belong to the protection scope of the present invention.

[0028] Furthermore, in the description of the present invention, the directions or positional relationships indicated by terms such as “upper”, “lower”, “left”, “right”, “front” and “back” are based on the directions or positional relationships in the accompanying drawings and are merely simplified descriptions for the convenience of describing the present invention, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present invention.

[0029] Figure 1 is a side view showing a laser radar capable of reducing a blind spot according to a first embodiment of the present invention. Figure 2 is a perspective view showing a transmitting lens and a receiving lens according to a first embodiment of the present invention. Figure 3 is a top view showing a transmitting lens and a receiving lens according to a first embodiment of the present invention. Figure 4 is a side view showing a transmitting lens according to a first embodiment of the present invention.

[0030] like Figures 1 to 4 As shown, the laser radar capable of reducing blind spots according to the first embodiment of the present invention may include a transmitting unit 100 , a receiving unit 200 , a transmitting lens 300 , a receiving lens 400 and a substrate 500 .

[0031] The transmitting unit 100 can emit laser light and make the laser light return to the laser radar after being reflected by an object outside the laser radar, so that the distance between the surrounding objects and the laser radar can be measured by the time of flight (TOF) method.

[0032] The emitting unit 100 may be an edge emitting laser (EEL) or a vertical cavity surface emitting laser (VCSEL). The laser of the edge emitting laser (EEL) is emitted parallel to the substrate, while the laser of the vertical cavity surface emitting laser (VCSEL) is emitted perpendicular to the substrate. In the present invention, the emitting unit 100 may be any type as long as it can emit laser light upward.

[0033] The receiving unit 200 can receive the laser that is emitted from the transmitting unit 100 and returns to the laser radar after being reflected by an object outside the laser radar.

[0034] The receiving unit 200 may be an avalanche photodiode (APD) or a single photon avalanche diode (SPAD). Moreover, the type of the receiving unit 200 is not limited thereto. The specific type of the receiving unit 200 may be appropriately selected by those skilled in the art within the scope of known photoelectric sensors.

[0035] The transmitting unit 100 and the receiving unit 200 may be disposed on the same substrate 500. The substrate 500 may be provided with a driving circuit for driving the transmitting unit 100 to emit laser light, a control circuit for controlling the transmitting unit 100 and the receiving unit 200, and the like.

[0036] The laser light emitted from the emitting part 100 may be incident on the emitting lens 300 located in front of the optical path of the emitting part 100. The laser light incident on the emitting lens 300 may be emitted from the upper end of the emitting lens 300 after being reflected twice by the emitting lens 300.

[0037] Below, refer to Figure 4 The transmitting lens 300 is described in more detail.

[0038] like Figure 4 As shown, the transmitting lens 300 may be an integrated "z"-shaped lens. That is, the transmitting lens 300 may be a lens with two corners. The corners may be 90° corners. Therefore, the laser light incident on the transmitting lens 300 may be reflected twice in the transmitting lens 300 and then emitted upward.

[0039] For convenience of description, the portion of the emitting lens 300 where the laser beam enters the emitting lens is referred to as an incident portion 310, and the portion of the emitting lens 300 where the laser beam exits the emitting lens is referred to as an exit portion 320. Furthermore, a corner of the emitting lens 300 close to the incident portion 310 is referred to as a first corner portion 330, and a corner of the emitting lens 300 close to the exit portion 320 is referred to as a second corner portion 340.

[0040] The incident portion 310 of the emitting lens 300 can play a collimating role. Specifically, the laser emitted from the emitting portion 100 can have a predetermined divergence angle, and the incident portion 310 of the emitting lens 300 can collimate the laser emitted from the emitting portion 100, thereby reducing the divergence angle of the laser. In addition, the incident portion 310 can have a convex lens shape, so that the laser can be collimated. Further, the incident portion 310 can be a spherical lens. Further, the incident portion 310 can have a positive optical focal length.

[0041] The first corner portion 330 and the second corner portion 340 can be used to change the direction of the laser incident from the incident portion 310. More specifically, the first corner portion 330 and the second corner portion 340 can cause the incident laser to produce total reflection so that the light incident to the first corner portion 330 is moved a predetermined distance in the horizontal direction and emitted. Therefore, the output light of the laser radar and the receiving lens can have the same central axis. The above-mentioned predetermined distance can be changed by changing the distance between the first corner portion 330 and the second corner portion 340. In addition, the center of the translated laser is preferably located at the center of the receiving portion 200 and / or the receiving lens 400.

[0042] Furthermore, the laser can be totally reflected at the first corner portion 330 and the second corner portion 340. The first corner portion 330 and the second corner portion 340 can reflect the incident laser by using the total reflection principle. The collimation degree of the incident portion 310 can be set to enable the laser incident on the emission lens 300 to be totally reflected at the first corner portion 330 and the second corner portion 340 without leaking from the side of the emission lens 300. If the collimation degree of the incident portion 310 is not enough, the laser may have a large divergence angle and cannot be totally reflected at the first corner portion 330 or the second corner portion 340, so that part of the laser leaks out; if the collimation degree of the incident portion 310 is too high, time and cost may be wasted when processing the incident portion 310. Alternatively, a reflective material (for example, a reflective film) may be provided at the first corner portion 330 and the second corner portion 340 to realize the reflection function.

[0043] The laser light totally reflected at the first corner portion 330 and the second corner portion 340 may travel toward the emission portion 320 and be emitted from the emission portion 320 to the outside of the emission lens (or the outside of the laser radar). The concave-convex degree of the emission portion 320 may be appropriately changed as needed. When it is necessary to make the laser light emitted from the emission lens 300 have a predetermined divergence angle, the emission lens 300 may have a concave lens shape; when it is necessary to make the laser light emitted from the emission lens 300 have a higher degree of collimation, the emission lens 300 may have a convex lens shape; or the emission lens 300 may also have a plane lens shape.

[0044] As described above, the laser light emitted from the emission lens 300 may be translated by a predetermined distance compared to the laser light incident to the emission lens 300, and the collimation degree of the emitted laser light may be higher than that of the incident laser light.

[0045] The receiving lens 400 can focus the laser beam that is irradiated to an object outside the laser radar and then returned to the receiving unit 200. Therefore, the receiving lens 400 can be formed into a convex lens. Also, it can be formed into a convex lens having a circular cross section and having four corners cut longitudinally into a quadrilateral shape (see Figures 1 to 3 ). In addition, the receiving lens 400 may have positive optical power. In order to reduce system aberration and improve the receiving efficiency of optical power, the receiving lens 400 may also adopt an aspherical optical lens, so that more light energy can be focused on the surface of the receiving part 200 for receiving and converting the optical signal into an electrical signal.

[0046] Hereinafter, the positional relationship among the transmitting unit 100 , the receiving unit 200 , the transmitting lens 300 , and the receiving lens 400 according to the first embodiment of the present invention will be described.

[0047] like Figure 1 As shown, the laser emitted from the emitting unit 100 is incident on the incident portion 310 of the emitting lens 300 and is collimated. Therefore, the central axis of the laser emitted by the emitting unit 100 and the main axis of the incident portion 310 of the emitting lens 300 are preferably located on the same straight line. However, considering the process error, the above two axes may not be accurately located on the same straight line, and there may be a predetermined deviation.

[0048] Furthermore, the laser reflected by the external object of the laser radar is focused by the receiving lens 400 when returning and irradiates the receiving unit 200. Therefore, the main axes of the receiving unit 200 and the receiving lens 400 are preferably located on the same straight line. However, considering the process error, there may be a predetermined deviation.

[0049] Furthermore, at least a portion of the emission portion 320 of the transmitting lens 300 may be located in the path of the laser from an object outside the laser radar to the receiving lens 400. Thus, the blind spot between the detection signal emitted from the transmitting lens 300 and the echo signal received by the receiving unit 200 may be reduced.

[0050] Alternatively, at least a portion of the emission portion 320 of the transmitting lens 300 may also be located on a path of the laser light from the receiving lens 400 to the receiving unit 200 .

[0051] When viewed from above, Figure 3As shown, the optical center of the emission portion 320 of the transmitting lens 300 can overlap with the optical center of the receiving lens 400. Moreover, when observed from above, the optical center of the emission portion 320 of the transmitting lens 300, the optical center of the receiving lens 400 and the receiving portion 200 can overlap. In other words, the main axis of the emission portion 320 of the transmitting lens 300, the main axis of the receiving lens 400 and the receiving portion 200 can be located on the same straight line. Among them, any point of the receiving portion 200 can be located on the same straight line with the optical center of the emission portion 320 of the transmitting lens 300 and the optical center of the receiving lens 400. Moreover, the extension direction of the transmitting lens 300 from the incident portion 310 to the first corner portion 330 can be parallel to the straight line. The blind spot between the detection signal emitted by the laser radar and the echo signal returned after reflection from the external object can be minimized by the above-mentioned setting method.

[0052] Furthermore, if Figure 3 As shown, when viewed from above, the transmitting lens 300 can block the middle area and a part of the area below the receiving lens 400. In addition, a light-absorbing material or a light-reflecting material can be provided on the side of the transmitting lens 300 to prevent the laser from passing through the transmitting lens 300 from the side of the transmitting lens 300 and entering the receiving lens 400. Therefore, the receiving lens 400 can receive the echo signal emitted from the transmitting unit 100 and reflected by the object in other areas except the middle area and a part of the area below.

[0053] Alternatively, the side surface of the transmitting lens 300 can be formed transparently, so that the echo signal emitted from the transmitting unit 100 and reflected by the object in the middle area or a part of the lower area can also pass through the transmitting lens 300 and the receiving lens 400 and be received by the receiving unit 200.

[0054] Although the above description shows and illustrates the case where the emission portion 320 of the transmitting lens 300 is formed above the receiving lens 400, the emission portion 320 of the transmitting lens 300 may also be formed below the receiving lens 400. That is, the laser light that returns to the laser radar after being reflected by an external object of the laser radar may first be focused by the receiving lens 400 and then partially blocked by the transmitting lens 300 before entering the receiving portion 200.

[0055] With the structure described above, the laser emitted by the transmitting unit 100 can be moved in the horizontal direction by the transmitting lens to reduce the blind spot between the transmitting unit 100 and the receiving unit 200. In addition, by forming the transmitting lens 300 integrally, the process required for optical path alignment can be simplified when the receiving lens 300 is set. In addition, compared with the case where the transmitting unit 100 is directly set in front of the optical path of the receiving unit 200, the length in the vertical direction can be reduced. In addition, the transmitting unit 100 and the receiving unit 200 can be set on the same substrate, so the substrate structure can be simplified.

[0056] Reference Figure 5 A laser radar capable of reducing blind spots according to a second embodiment of the present invention is described. Figure 5 is a side view showing an integrated lens according to a second embodiment of the present invention.

[0057] The laser radar according to the second embodiment of the present invention is different from the laser radar according to the first embodiment of the present invention in that the second embodiment does not have the transmitting lens 300 and the receiving lens 400 as in the first embodiment, but has Figure 5 The integrated lens shown.

[0058] The integrated lens may be a form in which the transmitting lens 300 and the receiving lens 400 are integrated, and may include a transmitting lens portion and a receiving lens portion.

[0059] Specifically, the integrated lens may be formed by inserting the area above the second corner portion 340 of the transmitting lens 300 into the receiving lens 400 to form an integrated lens. That is, the emission portion 320 of the transmitting lens 300 may be inserted into a hole formed in the receiving lens 400 .

[0060] Alternatively, the area above the second corner portion 340 of the transmitting lens 300 may be removed, and the transmitting lens 300 may be closely attached to the bottom of the receiving lens 400. Therefore, the laser light incident on the incident portion 310 of the transmitting lens 300 may be emitted to the outside through the receiving lens 400 after being totally reflected by the first corner portion 330 and the second corner portion 340. The area of ​​the upper surface of the receiving lens 400 where the laser light is emitted may be further processed into a concave shape or a convex shape as appropriate according to the divergence angle required for the emitted laser light.

[0061] Therefore, the integrated lens according to the second embodiment of the present invention can simultaneously function as the transmitting lens 300 and the receiving lens 400 .

[0062] By integrating the lens as described above, the number of components of the LiDAR can be reduced, thereby simplifying the assembly process.

[0063] In addition, the laser radar according to the first embodiment of the present invention may further include a rotating unit not shown. The rotating unit can rotate the transmitting unit 100, the receiving unit 200, the transmitting lens 300, the receiving lens 400 and the substrate 500 as described above together. The rotation may be a 360° rotation, so that objects within a 360° range can be detected by the laser radar as described above.

[0064] The above-described embodiments of the apparatus and method are merely illustrative, wherein the separated units described may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one location or distributed on multiple network units. Some or all of the modules may be selected according to actual needs to implement the technical solution of the present invention.

Claims

1. A laser radar, characterized in that: include: A transmitting unit capable of emitting laser light; An emitting lens, located in the light exit path of the emitting portion, having an incident portion for causing the laser to enter the emitting lens and an exit portion for causing the laser to exit from the emitting lens, the emitting lens extending from the incident portion to the exit portion and including a first corner portion and a second corner portion; A receiving unit, receiving the laser light emitted from the transmitting unit and reflected by an object outside the laser radar; The receiving lens is capable of changing the path of the laser beam emitted from the transmitting unit and reflected from the object so that the laser beam is irradiated to the receiving unit. The laser is reflected at the first corner and the second corner of the emitting lens. The main axis of the emitting portion of the transmitting lens and the main axis of the receiving lens are located on the same straight line, An extension direction of the emitting lens from the incident portion to a first corner portion close to the incident portion is parallel to the straight line; The receiving part and the transmitting part are arranged on the same substrate; The laser is totally reflected at the first corner portion and then totally reflected at the second corner portion before being emitted from the emission portion; The receiving portion is also located on the straight line; The incident portion of the emission lens has a convex lens shape.

2. A laser radar, characterized in that: include: A transmitting unit capable of emitting laser light; A receiving unit, receiving the laser light emitted from the transmitting unit and reflected by an object outside the laser radar; The integrated lens comprises a transmitting lens portion and a receiving lens portion, The emitting lens portion is located in the light exit path of the emitting portion, and has an incident portion for incident laser light into the emitting lens portion and an exit portion for laser light to be emitted from the emitting lens portion. The emitting lens portion extends from the incident portion to the exit portion, and includes a first corner portion and a second corner portion. The receiving lens unit is capable of changing the path of the laser beam emitted from the transmitting unit and reflected from the object so that the laser beam is irradiated to the receiving unit. The emission portion of the transmitting lens portion is inserted into the hole of the receiving lens portion or the emission portion of the transmitting lens portion is closely attached to one side of the receiving lens portion. The laser is reflected at the first corner and the second corner of the emitting lens part. The main axis of the emission portion of the transmitting lens portion and the main axis of the receiving lens portion are located on the same straight line, The extending direction of the emitting lens portion from the incident portion to the first corner portion close to the incident portion is parallel to the straight line; The receiving part and the transmitting part are arranged on the same substrate; The laser is totally reflected at the first corner portion and then totally reflected at the second corner portion before being emitted from the emission portion; The receiving portion is also located on the straight line; The incident portion of the emission lens portion has a convex lens shape.

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