A non-coaxial laser radar

Abstract

The present application relates to the field of laser radar, and in particular to a non-coaxial laser radar. The present application discloses a non-coaxial laser radar, including a transmitting module, a receiving module, and a spectroscopic module. The transmitting module and the receiving module are non-coaxial. The transmitting module is used to transmit a laser beam; the spectroscopic module is used to divide the laser beam into multiple beams and emit them to a target area, and the multiple beams detect different directions; the receiving module is used to receive and process multiple reflected echo beams. The present application uses a wedge prism or an N-face prism or a prism with a semi-transmissive and semi-reflective function as a spectroscopic module to realize the spectroscopic function of a non-coaxial laser radar, thereby expanding the detection field of view. The present application has a simple optical structure and low energy loss.

Description

Technical Field

[0001] The present application relates to a laser radar, and in particular to a non-coaxial laser radar. Background Art

[0002] Non-coaxial single-point ranging optical radar is a type of laser radar. The transmitting optical axis and receiving optical axis of non-coaxial laser radar are parallel but not coincident. Figure 1 As shown; the views of the transmitting and receiving optical axes in the A direction are coincident, as shown Figure 2 As shown. In applications, non-coaxial single-point ranging optical radars will need to monitor changes in a large area at the same time, so the detection field of view needs to be expanded. There are two methods in the prior art to expand the detection field of view. The first method is to use an optical system to simply expand the field of view of transmission and reception. This method will cause the complexity of the optical system and a significant decrease in energy utilization, thereby greatly reducing the range. Usually, the optical radar module with an angle of about 20-40° has a whiteboard ranging of less than 10 meters and a blackboard ranging of less than 5 meters. In addition, simply expanding the field of view of transmission and reception, the large-scale illumination of the light spot will result in that when the size of the target object is smaller than the size of the light spot, the returned light is only the part reflected on the target object, and the remaining energy cannot be used and is wasted. The second method is to rotate and scan the single-point radar to achieve measurement at a larger angle. This requires a rotating and driving structure, which requires an increase in large installation space and system structure costs. Summary of the invention

[0003] The purpose of this application is to propose a non-coaxial laser radar to solve the problems of complex optical system and low energy utilization when the existing non-coaxial laser radar expands the detection field of view.

[0004] To achieve this purpose, the present application embodiment adopts the following technical solutions:

[0005] On the one hand, a non-coaxial laser radar is characterized in that it includes a transmitting module, a receiving module, and a spectroscopic module, wherein the transmitting module and the receiving module are non-coaxial,

[0006] The transmitting module is used to transmit a laser beam;

[0007] The receiving module is used to receive and process the reflected echo light beam;

[0008] The light splitting module is used to split the laser beam into multiple beams and emit them to the target area. The multiple beams detect different directions. The reflected multiple echo beams are combined by the light splitting module and then enter the receiving module.

[0009] In a possible implementation, the light splitting module is a wedge prism, an N-face prism, or a prism with a semi-transparent and semi-reflective function.

[0010] In a possible implementation, when the light splitting module is a wedge prism, a portion of the laser beam is refracted by the prism, and another portion is emitted along the original optical path, and the angle between the refracted beam and the beam emitted along the original beam is 0-30°.

[0011] In a possible implementation, when the light splitting module is an N-face prism, the N-face prism splits the laser light beam into N-1 beams, 3≦N≦5.

[0012] In a possible implementation, the included angle of the split light is 0-70°.

[0013] In a possible implementation, when the light splitting module is a three-sided prism, the laser beam is split into two beams, and the angle between the two split beams is 0-30°.

[0014] In a possible implementation, when the light splitting module is a prism with a semi-transmissive and semi-reflective function, the laser beam is split into two beams, and the angle between the two split beams is 0-70°.

[0015] In a possible implementation, the prism with semi-transmissive and semi-reflective functions has a semi-transmissive and semi-reflective surface and a fully reflective surface. When the laser beam enters the semi-transmissive and semi-reflective surface, a portion of it is transmitted, and a portion of it is reflected from the semi-transmissive and semi-reflective surface to the fully reflective surface, and then reflected from the fully reflective surface.

[0016] In a possible implementation, the semi-transparent and semi-reflective surface is coated with a semi-transparent and semi-reflective film, and the fully-reflective surface is not coated or is coated with a reflective film.

[0017] In a possible implementation, the transmissivity of the semi-transparent and semi-reflective surface is 10-90%, the reflectivity is 10-90%, and the sum of the transmissivity and the reflectivity is 95-100%.

[0018] The present application uses a wedge prism or an N-face prism or a prism with a semi-transmissive and semi-reflective function as a light splitting module to achieve light splitting of a non-coaxial laser radar, thereby expanding the detection field of view. The present application has a simple optical structure and low energy loss. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a front view of a background technology device.

[0020] Figure 2 It is a view of the background technology device in direction A.

[0021] Figure 3 This is the view in direction A of the present application (the light splitting module is a wedge-shaped prism).

[0022] Figure 4 This is the view in direction A of this application (the light splitting module is a three-sided prism).

[0023] Figure 5 This is a view in direction A of the present application (the light splitting module is a prism with semi-transparent and semi-reflective functions).

[0024] In the figure: 1. Transmitting module; 2. Receiving module; 3. Wedge-shaped prism; 4. Three-sided prism; 5. Prism with semi-transparent and semi-reflective function; 6. Semi-transparent and semi-reflective surface; 7. Fully reflective surface. DETAILED DESCRIPTION

[0025] The technical solution of the present application is further explained below with reference to the accompanying drawings and through specific implementation methods.

[0026] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0027] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present application.

[0028] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present application described here. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0029] like Figure 3 As shown, a non-coaxial laser radar includes a transmitting module 1, a receiving module 2, and a spectrometer module. The transmitting module 1 and the receiving module 2 are non-coaxial.

[0030] The transmitting module 1 is used to transmit a laser beam;

[0031] The receiving module 2 is used to receive and process the reflected echo light beam;

[0032] The light splitting module is used to split the laser beam into multiple beams and emit them to the target area. The multiple beams detect different directions. The reflected multiple echo beams are combined by the light splitting module and enter the receiving module 2.

[0033] As can be seen from the background technology, the transmitting optical axis and the receiving optical axis of the non-coaxial laser radar are parallel but not overlapped, and the views of the transmitting and receiving optical axes in the direction A overlap. This embodiment adopts a spectroscopic module to divide the laser beam into multiple beams and emit them to the target area. The multiple beams detect different directions. The reflected multiple beams of echo light enter the receiving module 2 after being combined by the spectroscopic module. The views of the laser beam after the spectroscopic splitting and the multiple beams of echo light after the reflection in the direction A also overlap, thus realizing the spectroscopic splitting of the non-coaxial laser radar.

[0034] The embodiment of the present application only needs one spectrometer module to realize the spectrometry of non-coaxial laser radar, and does not need to go through a more complex optical system for spectrometry. Therefore, the structure is simple and the energy loss is small.

[0035] The light splitting module is a wedge prism 3 or an N-face prism or a prism 5 with a semi-transparent and semi-reflective function. Figure 3 The light splitting module is a wedge-shaped prism 3 .

[0036] The light splitting module uses a wedge prism 3, a part of the laser beam is refracted by the prism, and the other part is emitted along the original light path, and the angle between the refracted beam and the beam emitted along the original beam is 0-30°.

[0037] The light splitting module adopts a wedge prism 3 to refract a part of the laser beam and emit a part along the original optical path. The angle between the refracted beam and the beam emitted along the original optical path is 0-30°. The laser beam can detect in two directions at the same time, expanding the detection field of view.

[0038] When the light splitting module is an N-face prism, the N-face prism splits the laser beam into N-1 beams, 3≦N≦5.

[0039] The angle of the split light is 0-70°.

[0040] When the beam splitter adopts an N-face prism, the N-face prism splits the laser beam into N-1 beams, and the laser beams are emitted from N-1 faces except the incident face, and detect in different directions. After being irradiated on the target and reflected, the N-1 echo beams are combined by the N-face prism and enter the receiving module 2. The split laser beam and the echo beam are visually overlapped in the A direction. When an N-face prism is used, the split beams shall not exceed 4 beams. If more than 4 beams are used, the energy of a single beam is too low to meet the measurement needs, so N cannot be greater than 5.

[0041] like Figure 4As shown, when the light splitting module is a three-sided prism 4, the laser beam is split into two beams, and the angle between the two split beams is 0-30°.

[0042] like Figure 5 As shown, when the light splitting module is a prism 5 with a semi-transmissive and semi-reflective function, the laser beam is split into two beams, and the angle between the two split beams is 0-70°.

[0043] The semi-transmissive and semi-reflective prism 5 has a semi-transmissive and semi-reflective surface 6 and a fully reflective surface 7. When the laser beam enters the semi-transmissive and semi-reflective surface 6, a part of it is transmitted, and a part of it is reflected by the semi-transmissive and semi-reflective surface 6 to the fully reflective surface 7, and then reflected by the fully reflective surface 7.

[0044] When the beam splitter uses a prism 5 with a semi-transmissive and semi-reflective function, the laser beam is incident on the semi-transmissive and semi-reflective surface 6, a part of it is transmitted, and a part of it is reflected by the semi-transmissive and semi-reflective surface 6 to the full-reflective surface 7, and then reflected by the full-reflective surface 7. The angle between the transmitted light and the reflected light is 0-70°. The transmitted light and the reflected light detect different directions respectively. After irradiating the target, the reflected echo light beam enters the receiving module 2 through the prism 5 with a semi-transmissive and semi-reflective function, and the view of the transmitted light, the reflected light and the corresponding echo light beam in the A direction is overlapped.

[0045] The semi-transparent and semi-reflective surface 6 is coated with a semi-transparent and semi-reflective film, and the fully-reflective surface 7 is not coated with a film or is coated with a reflective film.

[0046] Ordinary prisms are made of glass or PET. In order to achieve a semi-transparent and semi-reflective effect, a semi-transparent and semi-reflective film is sputtered on one of the surfaces. The full-reflective surface 7 may not be coated, and the reflectivity of the material itself may be used for reflection, or a reflective film may be coated as needed.

[0047] The transmittance of the semi-transparent and semi-reflective surface is 10-90%, the reflectance is 10-90%, and the sum of the transmittance and the reflectance is 95-100%.

[0048] The technical principles of the present application are described above in conjunction with specific embodiments. These descriptions are only for explaining the principles of the present application and cannot be interpreted as limiting the scope of protection of the present application in any way. Based on the explanations herein, those skilled in the art can think of other specific implementation methods of the present application without creative work, and these methods will fall within the scope of protection of the present application.

Claims

1. A non-coaxial laser radar, characterized in that: It includes a transmitting module, a receiving module and a light splitting module, wherein the transmitting module and the receiving module are not coaxial. The transmitting module is used to transmit a laser beam; The receiving module is used to receive and process the reflected echo light beam; The emission optical axis of the laser beam emitted by the emission module and the receiving optical axis of the echo beam are parallel but not coincident; The spectroscopic module is used to split the laser beam into multiple beams and emit them to the target area. The multiple beams detect different directions, and the reflected multiple echo beams are combined by the spectroscopic module and enter the receiving module; the spectroscopic module is a wedge-shaped prism or an N-face prism; when the spectroscopic module is a wedge-shaped prism, a part of the laser beam is refracted through the prism, and the other part is emitted according to the original light path, and the angle between the refracted beam and the beam emitted according to the original beam is 0-30°; when the spectroscopic module is a three-faceted prism, the laser beam is refracted into two beams, and the angle between the two split beams is 0-30°.

2. The non-coaxial laser radar according to claim 1, characterized in that: The light splitting module is a prism with semi-transmissive and semi-reflective functions.

3. The non-coaxial laser radar according to claim 1, characterized in that: When the light splitting module is an N-face prism, the N-face prism splits the laser beam into N-1 beams, 3≦N≦5.

4. The non-coaxial laser radar according to claim 3, characterized in that: The angle of the split light is 0-70°.

5. The non-coaxial laser radar according to claim 1, characterized in that: When the light splitting module is a prism with a semi-transmissive and semi-reflective function, the laser beam is split into two beams, and the angle between the two split beams is 0-70°.

6. The non-coaxial laser radar according to claim 5, characterized in that: The prism with semi-transparent and semi-reflective function has a semi-transparent and semi-reflective surface and a fully reflective surface. When the laser beam enters the semi-transparent and semi-reflective surface, part of it is transmitted, and part of it is reflected from the semi-transparent and semi-reflective surface to the fully reflective surface and then reflected from the fully reflective surface.

7. The non-coaxial laser radar according to claim 6, characterized in that: The semi-transparent and semi-reflective surface is coated with a semi-transparent and semi-reflective film, and the fully-reflective surface is not coated with a film or is coated with a reflective film.

8. The non-coaxial laser radar according to claim 7, characterized in that: The transmittance of the semi-transparent and semi-reflective surface is 10-90%, the reflectance is 10-90%, and the sum of the transmittance and the reflectance is 95-100%.

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