A laser radar scanning head with isolated light receiving and light transmitting paths

Abstract

The present invention relates to the field of laser radar technology, and discloses a laser radar scanning head with isolated light receiving and light path, comprising: a transmitting mirror assembly, comprising an output mirror, a receiving mirror surrounding the output mirror, and a first isolation lens barrel and a second isolation lens barrel isolating the output mirror from the receiving mirror and being arranged on both sides of the normal line of the output mirror; the internal spaces of the first isolation lens barrel and the second isolation lens barrel are connected to the surface of the output mirror; a reflector assembly has the same structure as the transmitting mirror assembly; and a window plate assembly, comprising a third isolation lens barrel, an output window plate arranged in the third isolation lens barrel of the reflector assembly, and a receiving window plate arranged outside the third isolation lens barrel, the output window plate forms an acute angle with the central axis of the third isolation lens barrel, the receiving window plate is perpendicular to the central axis of the third isolation lens barrel, the third isolation lens barrel is connected to the first isolation lens barrel of the reflector assembly and is coaxially arranged, so as to prevent the output laser beam from entering the receiving system before exiting the system.

Description

Technical Field

[0001] The present invention relates to the field of laser radar technology, and in particular to a laser radar scanning head with isolated light transmitting and receiving paths. Background Art

[0002] Mechanical methods for laser scanning include swing mirrors and rotating mirrors. Currently, the laser radar used in the field of environmental monitoring generally adopts the swing mirror form, such as Figure 5 As shown, the scanning head is composed of a reflector 1, a reflector 2 and a window. The reflector 1 rotates around the z-axis to realize the scanning of the light beam on the xy plane. The reflector 2 rotates around the x-axis to realize the scanning of the light beam on the zy plane. The window plays a protective role.

[0003] The laser reflection and reception of this design are both through the reflector and the window. Due to the reflection of the window, the receiving part receives the echo signal of the window in addition to the echo signal in the atmosphere, and the echo signal of the window will annihilate the weak echo signal in the atmosphere, resulting in reduced radar detection sensitivity and performance. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a laser radar scanning head with isolated light transmission and receiving paths.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0006] A laser radar scanning head with isolated light transmitting and receiving paths, used to solve near-field light interference, comprising:

[0007] The transmitting mirror assembly comprises an output mirror, a receiving mirror coplanar with the output mirror and surrounding the output mirror, and a first isolation lens barrel and a second isolation lens barrel which isolate the output mirror from the receiving mirror and are arranged on both sides of the normal line of the output mirror; the internal spaces of the first isolation lens barrel and the second isolation lens barrel are connected to the surface of the output mirror;

[0008] The reflector assembly has the same structure as the emitting mirror assembly; the second isolation lens barrel of the reflector assembly is connected to the second isolation lens barrel of the emitting mirror assembly, and the central axes coincide with each other;

[0009] and a window piece assembly, comprising a third isolation lens barrel, an exit window piece arranged in the third isolation lens barrel of the reflector assembly, and a receiving window piece arranged outside the third isolation lens barrel, wherein the exit window piece forms an acute angle with the central axis of the third isolation lens barrel, and the receiving window piece is perpendicular to the central axis of the third isolation lens barrel;

[0010] The output mirror and the receiving mirror of the transmitting mirror assembly can rotate around the vertical axis; the output mirror and the receiving mirror of the reflecting mirror assembly can rotate around the horizontal axis.

[0011] Furthermore, the central axes of the first isolation lens barrel and the second isolation lens barrel form a right angle; during the operation of the laser radar scanning head, the second isolation lens barrel is always located in a horizontal plane.

[0012] Compared with the prior art, the beneficial technical effects of the present invention are:

[0013] The transmitting mirror assembly and the reflecting mirror assembly are isolated into a separate output mirror and a receiving mirror through the isolation lens barrel. The window piece is also isolated into a separate output window piece and a receiving window piece by the isolation lens barrel, isolating the output light path from the receiving light path. At the same time, the normal direction of the output window piece forms a certain angle with the output optical axis to prevent the return light of the window piece from returning along the original path, and prevent the output laser beam from entering the receiving system before leaving the system, thereby reducing the system noise floor and preventing the signal from being submerged in the near-field stray light noise. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the structure of the laser radar scanning head of the present invention;

[0015] Figure 2 It is a schematic diagram of the structure of the transmitting mirror assembly or the reflecting mirror assembly of the present invention;

[0016] Figure 3 It is a structural schematic diagram of the window piece assembly of the present invention;

[0017] Figure 4 It is a state diagram of the transmitting mirror assembly and the reflecting mirror assembly of the present invention when scanning and rotating to different angles;

[0018] Figure 5 It is a schematic diagram of the structure of a scanning head in the prior art. DETAILED DESCRIPTION

[0019] A preferred embodiment of the present invention is described in detail below with reference to the accompanying drawings.

[0020] like Figures 1 to 3 As shown, a laser radar scanning head with isolated light transmitting and receiving paths includes: a transmitting mirror assembly 1, a reflecting mirror assembly 2, and a window piece assembly 3.

[0021] The transmitting mirror assembly 1 includes an output mirror 11 , a receiving mirror 12 , a first isolation lens barrel 13 , and a second isolation lens barrel 14 . The output mirror 11 and the receiving mirror 12 are located in the same plane, and can be an integrated design or a split design; the first isolation lens barrel 13 and the second isolation lens barrel 14 are connected, and the first isolation lens barrel 13 and the second isolation lens barrel 14 separate the output mirror 11 and the receiving mirror 12 to achieve isolation of the output light path 4 from the receiving light path; the first isolation lens barrel 13 and the second isolation lens barrel 14 are located on both sides of the normal of the output mirror 11, the angle between the central axis of the first isolation lens barrel 13 and the normal of the output mirror 11 is A, and the angle between the central axis of the second isolation lens barrel 14 and the normal of the output mirror 11 is B, then A=B; in order to ensure that the output light path 4 will not be blocked by the isolation lens barrel during the scanning rotation of the emitting mirror assembly 1 and the reflecting mirror assembly 2, A=B=45° is required, then the central axes of the first isolation lens barrel 13 and the second isolation lens barrel 14 form a right angle, that is, the first isolation lens barrel 13 and the second isolation lens barrel 14 are orthogonally arranged.

[0022] The isolation lens barrel, the exit lens 11 and the receiving lens 12 can be fixed by glue.

[0023] The structure of the transmitting mirror assembly 1 is the same as that of the reflecting mirror assembly 2, and also includes an output mirror 11, a receiving mirror 12, a first isolation lens barrel 13, and a second isolation lens barrel 14. The difference is that the output mirror 11 of the transmitting mirror assembly 1 rotates around the vertical axis (z axis) to achieve the scanning of the light beam in the horizontal plane (xy plane); the output mirror 11 of the reflecting mirror assembly 2 rotates around the transverse axis (x axis) to achieve the scanning of the light beam in the vertical plane (yz plane). Figure 4 In (α, β), α represents the rotation angle of the transmitting mirror assembly 1 around the vertical axis, and β represents the rotation angle of the reflecting mirror assembly 2 around the horizontal axis.

[0024] The window plate assembly 3 includes a third isolation lens barrel 31, an exit window plate 34, a receiving window plate 32, and a tightening pressure ring 33; the exit window plate 34 is located in the third isolation lens barrel 31 and forms an acute angle with the central axis of the third isolation lens barrel 31; the receiving light window plate surrounds the outside of the third isolation lens barrel 31 and is fixed by tightening the pressure ring and the boss on the third isolation lens barrel 31.

[0025] The outgoing optical path 4 passes through the first isolation lens barrel 13, the exit mirror 11, and the second isolation lens barrel 14 of the transmitting mirror assembly 1, and then passes through the second isolation lens barrel 14, the exit mirror 11, and the first isolation lens barrel 13 of the reflecting assembly, and then passes through the third isolation lens barrel 31 and the exit window 34 to be emitted; the tilted setting of the exit light window can ensure that the laser will not return and damage the laser. The receiving light beam passes through the receiving window 32, the receiving mirror 12 of the reflecting mirror assembly 2, and the receiving mirror 12 of the transmitting mirror assembly 1, and is finally received. The transmitting mirror assembly 1 and the reflecting mirror assembly 2 isolate the separate exit mirror 11 and the receiving mirror 12 through the isolation lens barrel, and the window piece is also isolated by the isolation lens barrel into a separate exit window 34 and a receiving window 32, isolating the outgoing optical path 4 from the receiving optical path, preventing the emitted laser beam from entering the receiving system before leaving the system, reducing the system background noise, and preventing the signal from being submerged in the near-field stray light noise.

[0026] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention, and any reference numerals in the claims should not be regarded as limiting the claims involved.

[0027] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A laser radar scanning head with isolated light transmission and receiving paths, used to solve near-field light interference, characterized in that: include: The transmitting mirror assembly comprises an output mirror, a receiving mirror coplanar with the output mirror and surrounding the output mirror, and a first isolation lens barrel and a second isolation lens barrel which isolate the output mirror from the receiving mirror and are arranged on both sides of the normal line of the output mirror; the internal spaces of the first isolation lens barrel and the second isolation lens barrel are connected to the surface of the output mirror; The reflector assembly has the same structure as the emitting mirror assembly; the second isolation lens barrel of the reflector assembly is connected to the second isolation lens barrel of the emitting mirror assembly and is coaxially arranged; and a window assembly, comprising a third isolation lens barrel, an exit window arranged in the third isolation lens barrel of the reflector assembly, and a receiving window arranged outside the third isolation lens barrel, wherein the exit window forms an acute angle with the central axis of the third isolation lens barrel, the receiving window is perpendicular to the central axis of the third isolation lens barrel, and the third isolation lens barrel is connected to the first isolation lens barrel of the reflector assembly and is coaxially arranged; The isolation lens barrel is fixed to the exit mirror and the receiving mirror by glue; The output mirror and the receiving mirror of the transmitting mirror assembly can rotate around the vertical axis z-axis; the output mirror and the receiving mirror of the reflecting mirror assembly can rotate around the horizontal axis x-axis; The angle between the central axis of the first isolation lens barrel and the normal of the output mirror is A, and the angle between the central axis of the second isolation lens barrel and the normal of the output mirror is B; in order to ensure that the output light path will not be blocked by the isolation lens barrel during the scanning rotation of the transmitting mirror assembly and the reflecting mirror assembly, A=B=45° is required, so the central axes of the first isolation lens barrel and the second isolation lens barrel are at right angles; during the operation of the laser radar scanning head, the second isolation lens barrel is always located in the horizontal plane.

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