KR20200102900A - Lidar device - Google Patents

Abstract

The present invention relates to a lidar device including: a laser output unit for outputting a laser beam; a scanning unit which rotates along a rotation axis and reflects the laser beam output from the laser output unit toward an object; and a laser receiving unit which receives the laser beam reflected from the object through the scanning unit. The scanning unit includes: a transmission mirror which reflects the laser beam output from the laser output unit toward the object; and a receiving mirror which obtains the laser beam reflected from the object, but changes a light receiving path of the obtained laser beam therein to reflect the laser beam toward the laser receiver. The present invention can increase a measurable distance of the lidar device through a filter module.

Description

Lidar device {LIDAR DEVICE}

The present invention relates to a lidar device that obtains a distance of an object using a laser beam, and more particularly, to a lidar device that rotates 360 degrees and scans a peripheral area.

In recent years, LiDAR (Light Detection and Ranging) has been in the spotlight with interest in self-driving cars and driverless cars. Lida is a device that acquires surrounding distance information using a laser, and thanks to the advantage of being able to recognize objects in three dimensions with excellent precision and resolution, it is being applied to various fields such as drones and aircraft as well as automobiles.

Meanwhile, in order to improve the accuracy of the lidar device, it is necessary to process external noise such as sunlight and internal noise reflected from the inside of the lidar device and immediately incident on the sensor.

An object of the present invention is to provide a lidar device capable of 360-degree two-dimensional scanning.

Another object of the present invention is to increase the measurable distance of the lidar device through the filter module.

Another object of the present invention is to detect an object located at a distance with minimum power.

The problem to be solved by the present invention is not limited to the above-described problems, and problems that are not mentioned will be clearly understood by those of ordinary skill in the art from the present specification and the accompanying drawings. .

According to an aspect of the present invention, a laser output unit for outputting a laser beam; A scanning unit that rotates along a rotation axis and reflects the laser beam output from the laser output unit toward an object; And a laser receiver configured to receive a laser beam reflected from the object through the scanning unit, wherein the scanning unit includes a transmission mirror that reflects the laser beam output from the laser output unit toward the object, and Obtaining a laser beam, but including a receiving mirror for changing the light receiving path of the obtained laser beam therein to reflect toward the laser receiving unit, the receiving mirror includes a first reflection area and a second reflection area, the The first reflection area receives the laser beam reflected from the object, changes the flight path of the received laser beam, the second reflection area receives the laser beam from the first reflection area, and the laser receiver The first reflection area so that the received laser beam is reflected toward, the second reflection area receives as many laser beams as possible reflected from the first reflection area, and the received laser beam is reflected toward the light receiving unit. And a lidar device in which the second reflection area is symmetrical with respect to a central axis of the reception mirror may be provided.

According to another aspect of the present invention, a laser output unit for outputting a laser beam; A scanning unit that rotates along a rotation axis and reflects the laser beam output from the laser output unit toward an object; And a laser receiving unit configured to receive a laser beam reflected from the object through the scanning unit, wherein the scanning unit includes a transmission mirror that reflects the laser beam output from the laser output unit toward the object, and a laser reflected from the object A receiving mirror that acquires a beam but changes a light receiving path of the obtained laser beam therein to reflect it toward the laser receiving unit, and a filter module that is combined with the receiving mirror to filter some wavelength components of the laser beam reflected from the object Including, wherein the receiving mirror receives the laser beam reflected from the object, a first reflection area for changing a flight path of the received laser beam, and a laser beam from the first reflection area, the laser A lidar device including a second reflection area for reflecting the received laser beam toward a receiver may be provided.

The solution means of the subject of the present invention is not limited to the above-described solution means, and solutions that are not mentioned will be clearly understood by those of ordinary skill in the art from the present specification and the accompanying drawings. I will be able to.

According to an embodiment, a 360-degree 2D scan may be performed through the lidar device.

According to another embodiment, a measurable distance of the lidar device may be increased through the filter module.

According to another embodiment, an object located at a distant distance may be sensed with minimal power.

The effects of the present invention are not limited to the above-described effects, and effects that are not mentioned will be clearly understood by those of ordinary skill in the art from the present specification and the accompanying drawings.

1 is a block diagram illustrating a LiDAR device according to an exemplary embodiment.
2 is a block diagram illustrating a LiDAR device according to an exemplary embodiment.
3 is a diagram for describing a lidar device according to an exemplary embodiment.
4 is a diagram illustrating a lidar device according to an exemplary embodiment.
5 is a diagram for describing a lidar device according to another embodiment.
6 is a perspective view showing a LiDAR device according to an embodiment.
7 is a perspective view showing a lidar device according to an embodiment.
8 is a diagram for describing a lidar device according to another embodiment.
9 is a graph for explaining the effect of the filter module.
10 is a graph showing an example of a change in a center wavelength of a filter module according to an incident angle.
11 is a perspective view showing a LiDAR device according to an embodiment.

Since the embodiments described in the present specification are intended to clearly explain the spirit of the present invention to those of ordinary skill in the technical field to which the present invention pertains, the present invention is not limited by the embodiments described herein, and the present invention The scope of should be construed as including modifications or variations that do not depart from the spirit of the present invention.

The terms used in the present specification have been selected as general terms that are currently widely used in consideration of functions in the present invention, but this varies depending on the intention, custom, or the emergence of new technologies of those of ordinary skill in the technical field to which the present invention belongs. I can. However, if a specific term is defined and used in an arbitrary meaning unlike this, the meaning of the term will be separately described. Therefore, terms used in the present specification should be interpreted based on the actual meaning of the term and the entire contents of the present specification, rather than a simple name of the term.

The drawings attached to the present specification are for easy explanation of the present invention, and the shapes shown in the drawings may be exaggerated and displayed as needed to aid understanding of the present invention, so the present invention is not limited by the drawings.

In the present specification, when it is determined that a detailed description of a known configuration or function related to the present invention may obscure the subject matter of the present invention, a detailed description thereof will be omitted as necessary.

According to an embodiment, a laser output unit for outputting a laser beam; A scanning unit that rotates along a rotation axis and reflects the laser beam output from the laser output unit toward an object; And a laser receiver configured to receive a laser beam reflected from the object through the scanning unit, wherein the scanning unit includes a transmission mirror that reflects the laser beam output from the laser output unit toward the object, and Obtaining a laser beam, but including a receiving mirror for changing the light receiving path of the obtained laser beam therein to reflect toward the laser receiving unit, the receiving mirror includes a first reflection area and a second reflection area, the The first reflection area receives the laser beam reflected from the object, changes the flight path of the received laser beam, the second reflection area receives the laser beam from the first reflection area, and the laser receiver The first reflection area so that the received laser beam is reflected toward, the second reflection area receives as many laser beams as possible reflected from the first reflection area, and the received laser beam is reflected toward the light receiving unit. And a lidar device in which the second reflection area is symmetrical with respect to a central axis of the reception mirror may be provided.

Here, the transmission mirror may rotate 360 degrees based on a rotation axis.

Here, the receiving mirror may rotate integrally with the transmitting mirror.

Here, the lidar device may further include a condensing lens for guiding the laser beam reflected from the receiving mirror to the laser receiving unit, and a central axis of the condensing lens may coincide with the rotation axis.

Here, the laser receiver may be disposed on the rotation shaft.

Here, the first reflection area is disposed to form a first angle with a virtual surface perpendicular to a virtual line extending from a laser beam incident on the transmission mirror after being output from the laser output unit, and the second reflection area is , Is disposed to form a second angle with the virtual surface, and a sum of the first angle and the second angle may be 90 degrees.

Here, the first angle may be greater than at least twice the second angle.

Here, the central axis of the receiving mirror may be inclined by 45 degrees with the rotation axis.

Here, the receiving mirror may have a truncated cone shape.

According to another embodiment, a laser output unit for outputting a laser beam; A scanning unit that rotates along a rotation axis and reflects the laser beam output from the laser output unit toward an object; And a laser receiving unit configured to receive a laser beam reflected from the object through the scanning unit, wherein the scanning unit includes a transmission mirror that reflects the laser beam output from the laser output unit toward the object, and a laser reflected from the object A receiving mirror that acquires a beam but changes a light receiving path of the obtained laser beam therein to reflect it toward the laser receiving unit, and a filter module that is combined with the receiving mirror to filter some wavelength components of the laser beam reflected from the object Including, wherein the receiving mirror receives the laser beam reflected from the object, a first reflection area for changing a flight path of the received laser beam, and a laser beam from the first reflection area, the laser A lidar device including a second reflection area for reflecting the received laser beam toward a receiver may be provided.

Here, the filter module may filter a partial wavelength component of a laser beam incident on or emitted from the reception mirror.

Here, the filter module may be disposed to be perpendicular to the central axis of the receiving mirror.

Here, when the laser beam incident on the filter module is incident at an angle of 45 degrees, a point at which the intensity of the laser beam passing through the filter module becomes maximum may be a 905 nm band.

Here, the full half width (FWHM) of the laser beam output from the laser output unit may be greater than the full half width of the laser beam obtained by the laser receiver.

LiDAR (Light Detection And Ranging) is a device that detects an object using a laser.

As a method of measuring the lidar, there are a time of flight (TOF) method, a triangulation method, an interferometry method, and the like. Hereinafter, for convenience of description, the flight time measurement method will be mainly described, and it is obvious that the LiDAR device to be described later can detect an object based on other methods.

1 is a block diagram illustrating a LiDAR device according to an exemplary embodiment.

Referring to FIG. 1, the lidar apparatus 1000 may include a laser output unit 100, a scanning unit 200, a laser receiving unit 300, and a control unit 400. The laser beam output from the laser output unit 100 is irradiated to an object through the scanning unit 200, and a laser beam reflected from the object may be received through the laser receiving unit 300. The controller 400 may control each operation of the laser output unit 100, the scanning unit 200, and the laser receiving unit 300.

Hereinafter, each configuration of the lidar device will be described in detail.

The laser output unit 100 may emit or output a laser beam.

The laser output unit 100 may be provided as a laser diode, a VICSEL (Vertical Cavity Surface Emitting Laser), or a VECSEL (Vertical External Cavity Surface Emitting Laser).

The laser output unit 100 may be provided in various forms. For example, the laser output unit 100 may include a plurality of laser elements arranged in a one-dimensional or two-dimensional array form. Alternatively, the laser output unit 100 may be arranged in an irregular shape. The laser output unit 100 may be provided in plural.

The laser output unit 100 may output laser beams of various wavelengths. For example, the laser output unit 100 may output a laser beam of a 905 nm or 1550 nm band. When the laser output unit 100 includes a plurality of laser elements, some of the plurality of laser elements may output a laser beam of a 905 nm band, while others may output a laser beam of a 1550 nm band.

The scanning unit 200 may change the flight path of the laser beam. For example, the scanning unit 200 may guide the laser beam output from the laser output unit 100 to the object. Alternatively, the scanning unit 200 may guide the laser beam reflected from the object to the laser receiving unit 300.

The scanning unit 200 may change the flight path of the laser beam by refracting or reflecting the laser beam. For example, the scanning unit 200 may reflect the laser beam output from the laser output unit 100 toward the object. Alternatively, the scanning unit 200 may reflect the laser beam reflected from the object toward the laser receiving unit 300.

The scanning unit 200 may include various optical means. For example, the scanning unit 200 may include a lens, a prism, a mirror, or the like. The scanning unit 200 includes a micro lens, a microfluidie lens, an optical phase array (OPA), a polygonal mirror, a MEMS mirror, a galvano mirror, and a meta. It may include a metasurface or the like. Alternatively, the scanning unit 200 may include a filter member.

The scanning unit 200 may change optical characteristics of the laser beam. For example, the scanning unit 200 may modulate the phase of the laser beam. Alternatively, the scanning unit 200 may change the spectral characteristics of the laser beam. For example, the scanning unit 200 may change the center wavelength of the laser beam. The scanning unit 200 may block or block light other than the center wavelength of the laser beam output from the laser output unit 100.

The scanning unit 200 may include a plurality of sub-scanning units. For example, the scanning unit 200 may include a first sub-scanning unit provided as a lens and a second sub-scanning unit provided as a mirror.

The laser receiver 300 may detect or receive a laser beam. For example, the laser receiver 300 may detect a laser beam reflected from an object. Alternatively, the laser receiver 300 may sense a laser beam reflected from the scanning unit 200 after being reflected from the object.

The laser receiver 300 may convert an optical signal into an electric signal.

The laser receiver 300 may detect a laser beam based on the converted electrical signal. For example, the laser receiver 300 may detect a received laser beam by comparing the magnitude of the converted electrical signal with a predetermined threshold value.

The laser receiver 300 may include various optical means. For example, the laser receiver 300 may include a sensor, a lens, an optical filter, or the like.

The laser receiving unit 300 may include various sensor elements. For example, the laser receiver 300 may include APD (Avalanche Photodiode), SPAD (Single-photon avalanche diode), SiPM (Silicon Photo Multipliers), CMOS (Complementary metal-oxide-semiconductor), CCD (charge coupled device). I can.

The laser receiver 300 may be provided as one of the above-described sensor elements, or may be provided by combining a plurality of sensor elements.

The controller 400 may control each operation of the laser output unit 100, the scanning unit 200, and the laser receiving unit 300.

Hereinafter, a control operation of the controller 400 for the above components will be described.

The controller 400 may control the operation of the laser output unit 100. For example, the control unit 400 may control an emission timing of the laser beam emitted from the laser output unit 100. The controller 400 may control an emission period of the emitted laser beam. Alternatively, the controller 400 may control the intensity of the emitted laser beam. Alternatively, when the laser output unit 100 includes a plurality of laser output devices, the control unit 400 may determine which of the plurality of laser output devices to operate.

The controller 400 may control an operation of the scanning unit 200. For example, when the scanning unit 200 is provided as a rotating mirror, the controller 400 may control the rotational speed of the scanning unit 200. Alternatively, the controller 400 may adjust the rotation timing of the scanning unit 200 in consideration of the laser beam emission timing of the laser output unit 100.

The controller 400 may control the operation of the laser receiving unit 300. For example, when the laser receiving unit 300 includes a plurality of sensor elements, the control unit 400 may determine which of the plurality of sensor elements to operate.

2 is a block diagram illustrating a LiDAR device according to an exemplary embodiment.

Referring to FIG. 2, the lidar apparatus 1000 may include a laser output unit 100, a scanning unit 200, a laser receiving unit 300, and a control unit 400. The lidar device 1000 may detect or calculate a distance from the lidar device 1000 to the object Ob.

Hereinafter, the operation of the lidar device 1000 will be described.

The controller 400 may generate a laser beam emission signal. Based on the generated signal, the laser output unit 100 may emit or output a laser beam.

The control unit 400 may obtain a timing at which the laser beam is emitted.

The scanning unit 200 may guide a laser beam emitted or output from the laser output unit 100 to the object Ob. For example, the scanning unit 200 may guide the object Ob by refracting or reflecting the emitted or output laser beam.

The scanning unit 200 may change the shape of the emitted or output laser beam. For example, when the laser output unit 100 emits a laser beam in the form of a point light source, the scanning unit 200 may convert the laser beam in the form of a point light source into a laser beam in the form of a line. Alternatively, the scanning unit 200 may convert the laser beam in the form of the point light source into a laser beam in the form of a two-dimensional plane. Alternatively, when the laser output unit 100 emits a line-shaped laser beam, the scanning unit 200 may convert the line-shaped laser beam into a two-dimensional planar laser beam.

The scanning unit 200 may acquire a laser beam reflected from the object Ob.

The scanning unit 200 may guide the obtained laser beam to the laser receiving unit 300. For example, the scanning unit 200 may guide the laser receiving unit 300 by refracting or reflecting the obtained laser beam.

The control unit 400 may acquire a reception time point at which the laser receiver 300 receives the laser beam.

The controller 400 may obtain a flight time of the laser beam based on the emission time point and the reception time point. The controller 400 may obtain the flight distance of the laser beam based on the flight time. The controller 400 may obtain a distance from the lidar device 1000 to an object based on the flight distance.

In addition, the controller 400 may control each operation of the laser output unit 100, the scanning unit 200, and the laser receiving unit 300 as described above.

3 is a diagram for describing a lidar device according to an exemplary embodiment.

Referring to FIG. 3, the lidar apparatus 1000 may include a laser output unit 100, a scanning unit 200, and a laser receiving unit 300. The lidar device 1000 may obtain a distance from the lidar device 1000 to the object Ob by receiving a laser beam reflected from the object Ob after being emitted from the laser output unit 100.

The laser output unit 100 may emit or output a laser beam in one direction. For example, the laser output unit 100 may emit a laser beam toward the scanning unit 200 along the y-axis direction.

The scanning unit 200 may include a collimator 210, a transmission mirror 220, a reception mirror 230, and a condensing lens 240.

Hereinafter, each configuration of the scanning unit 200 will be described in detail.

The scanning unit 200 may include a collimator 210 that converts a laser beam provided from one side into a parallel beam. The collimator 210 may guide the laser beam emitted from the laser output unit 100 to the transmission mirror 220. The collimator 210 may convert the emitted laser beam into a parallel beam and guide it to the transmission mirror 220. The collimator 210 may be provided as a lens.

The transmission mirror 220 may acquire a laser beam provided from one side. The transmission mirror 220 may guide the acquired laser beam to the object Ob.

For example, the transmission mirror 220 may guide a laser beam emitted from the laser output unit 100 to the object. Alternatively, the transmission mirror 220 may guide the laser beam passing through the collimator 210 to the object Ob. The transmission mirror 220 may guide the laser beam to the object Ob by reflecting the emitted or guided laser beam.

The transmission mirror 220 may refract the obtained laser beam at various angles. For example, the transmission mirror 220 may refract the obtained laser beam by 90 degrees. The transmission mirror 220 may refract the laser beam incident in the y-axis direction in the x-axis direction.

The transmission mirror 220 may rotate at a predetermined angle based on one axis. For example, the transmission mirror 220 may rotate 360 degrees based on the y-axis. Alternatively, the transmission mirror 220 may be repeatedly driven in a predetermined range in the x-axis direction.

The rotation direction of the transmission mirror 220 may be related to a field of view (FOV) of the lidar device 1000. For example, the rotation based on the x-axis of the transmission mirror 220 may be related to the vertical FOV, and the rotation based on the y-axis of the transmission mirror 220 may be related to the horizontal FOV.

The transmission mirror 220 may have various shapes and may include at least one reflective surface. The shape of the reflective surface may vary. For example, the reflective surface may be provided in the form of a flat plate or may be provided in the form of a curved surface. The reflective surface may have a circular shape or an elliptical shape.

The transmission mirror 220 may be provided with various types of mirrors. For example, the transmission mirror 220 may be provided as a fixed mirror, or may be provided as a MEMS mirror or a galvano mirror that is repeatedly driven.

The transmission mirror 220 may be disposed in various positions. For example, the transmission mirror 220 may be disposed on an optical path of a laser beam emitted from the laser output unit 100 and directed to an object. The transmission mirror 220 may be disposed on the y-axis including the laser output unit 100.

The laser beam irradiated from the transmission mirror 220 to the object may be reflected by the object and then obtained by the reception mirror 230.

The receiving mirror 230 may acquire a laser beam reflected from the object. The receiving mirror 230 may guide the obtained laser beam to the laser receiving unit 300. For example, the reception mirror 230 may guide the laser receiver 300 by reflecting the obtained laser beam at least once.

The receiving mirror 230 may include a first reflective area 231 and a second reflective area 232.

The first reflective area 231 may acquire a laser beam reflected from the object. The first reflective area 231 may guide the obtained laser beam to the second reflective area 232. The first reflective area 231 may reflect the obtained laser beam toward the second reflective area 232. The first reflection area 231 may change the flight path of the acquired laser beam.

)만큼 경사지게 배치될 수 있다. 이에 따라, 제1 반사 영역(231)은 상기 획득되는 레이저 빔을 하방으로 굴절시킬 수 있다. 또는, 제1 반사 영역(231)은 레이저 출력부(100)로부터 출력된 후 송신 미러(220)로 입사되는 레이저 빔의 입사 방향을 따라 연장되는 가상의 선과 수직인 가상면과 제1 각도(

)를 이루도록 배치될 수 있다. 상기 가상면은 x축을 따라 형성될 수 있다. 상기 가상면은 제1 반사 영역(231)의 일단과 만날 수 있다. 도 3에서, 상기 가상면은 점선으로 표시될 수 있다.The first reflective area 231 may be disposed to be inclined from the x-axis or the y-axis. For example, the first reflection area 231 has a first angle upward from the x-axis (

) Can be arranged inclined. Accordingly, the first reflection region 231 may refract the obtained laser beam downward. Alternatively, the first reflection area 231 may be output from the laser output unit 100 and then the virtual surface perpendicular to the virtual line extending along the incidence direction of the laser beam incident on the transmission mirror 220 and a first angle (

) Can be arranged to achieve. The virtual surface may be formed along the x-axis. The virtual surface may meet one end of the first reflective area 231. In FIG. 3, the virtual surface may be indicated by a dotted line.

The second reflective area 232 may acquire a laser beam guided or reflected from the first reflective area 231. The second reflective area 232 may guide the obtained laser beam to the laser receiver 300. The second reflective area 232 may reflect the obtained laser beam toward the laser receiver 300. The second reflection area 232 may change the flight path of the acquired laser beam.

)만큼 경사지게 배치될 수 있다. 이에 따라, 제2 반사 영역(232)은 상기 획득되는 레이저 빔을 상방으로 굴절시킬 수 있다. 제2 반사 영역(232)은 상기 가상면과 제2 각도(

)를 이루도록 배치될 수 있다.The second reflective area 232 may be disposed to be inclined from the x-axis or the y-axis. For example, the second reflective region 232 has a second angle downward from the x-axis (

) Can be arranged inclined. Accordingly, the second reflection area 232 may refract the obtained laser beam upward. The second reflective area 232 has a second angle (

) Can be arranged to achieve.

The receiving mirror 230 may have various shapes. For example, the receiving mirror 230 may have a shape in which the first reflective area 231 and the second reflective area 232 are symmetrical with respect to one axis.

) 및 제2 각도(

)의 합은 90도가 될 수 있다.First angle (

) And the second angle (

The sum of) can be 90 degrees.

)의 크기는 제2 각도(

)의 크기보다 클 수 있다. 이에 따라, 수신 미러(230)는 대상체로부터 반사되는 레이저 빔을 상방으로 안내할 수 있다.First angle (

) Is the second angle (

Can be larger than the size of ). Accordingly, the receiving mirror 230 may guide the laser beam reflected from the object upward.

One end of the first reflective region 231 and one end of the second reflective region 232 may be placed on a virtual line parallel to the x-axis. Based on the virtual line, a first reflective area 231 may be positioned in a first direction, and a second reflective area 232 may be positioned in a second direction opposite to the first direction.

This is, assuming that the laser beam reflected from the object is incident on the receiving mirror 230 in parallel with the x-axis, when the length of the first reflection area 231 is greater than that in FIG. 3, the second reflection area 232 This is because the laser beam flying toward the laser receiver 300 may be blocked or shielded by the first reflective area 231. Alternatively, when the length of the second reflective area 232 is larger than that in FIG. 3, the laser beam flying from the object toward the first reflective area 231 may be blocked or shielded by the second reflective area 232. .

)의 크기는 제2 각도(

)의 크기보다 적어도 2배 이상 클 수 있다. 이는 대상체로부터 반사되는 레이저 빔의 획득량을 확보하기 위함일 수 있다.First angle (

) Is the second angle (

It may be at least twice the size of ). This may be to secure an acquisition amount of the laser beam reflected from the object.

The first reflective area 231 and the second reflective area 232 may be arranged to fly along the y-axis direction after the laser beam reflected from the object is reflected by the receiving mirror 230.

Meanwhile, the receiving mirror 230 may rotate along one axis and obtain a laser beam reflected from the object. For example, the reception mirror 230 may rotate 360 degrees based on the y-axis.

The receiving mirror 230 and the transmitting mirror 220 may rotate along the same axis of rotation.

The receiving mirror 230 may rotate integrally with the transmitting mirror 220. The reception mirror 230 may be integrally formed with the transmission mirror 220.

The direction of rotation of the reception mirror 230 may be related to a field of view (FOV) of the lidar device 1000. For example, the rotation based on the x-axis of the receiving mirror 230 may be related to the vertical FOV, and the rotation based on the y-axis of the receiving mirror 230 may be related to the horizontal FOV.

The lidar device 1000 may include a condensing lens 240 for guiding a laser beam reflected from the reception mirror 230 to the laser reception unit 300.

The condensing lens 240 may acquire a laser beam reflected from the receiving mirror 230. The condensing lens 240 may guide the obtained laser beam to the laser receiver 300. For example, the condensing lens 240 may guide the laser receiver 300 by refracting the obtained laser beam. Alternatively, the condensing lens 240 may focus the obtained laser beam to one point on the laser receiver 300.

The condensing lens 240 may be disposed between the receiving mirror 230 and the laser receiving unit 300. For example, the condensing lens 240 may be placed on the rotation axis of the receiving mirror 230, and may be disposed between the receiving mirror 230 and the laser receiving unit 300. The central axis of the condensing lens 240 may be formed to overlap the rotation axis of the receiving mirror 230. That is, the central axis of the condensing lens 240 may be the same as the rotation axis of the receiving mirror 230.

The condensing lens 240 may have a predetermined diameter d. The diameter d may correspond to the length of the second reflective area 232 along the x-axis direction. The diameter (d) may be equal to or smaller than the length of the second reflective region 232 along the x-axis direction.

The lidar device 1000 may include a laser receiver 300 that acquires a laser beam guided by the condensing lens 240. As described above, the laser receiver 300 may detect the obtained laser beam, and a detailed description thereof will be omitted.

The laser receiving unit 300 may be located on the opposite side to the laser output unit 100 based on the scanning unit 200.

The laser output unit 100, the scanning unit 200, and the laser receiving unit 300 may be disposed to be located on the same axis. For example, the rotation axis of the scanning unit 200 may coincide with the central axis of the laser receiving unit 300. The central axis of the laser output unit 100 may coincide with the rotation axis of the scanning unit 200.

The emission direction of the laser beam emitted from the laser output unit 100 may be parallel to the rotation axis of the scanning unit 200. The emitted laser beam may fly along the rotation axis of the scanning unit 200.

Alternatively, the emission direction of the laser beam incident on the transmission mirror 220 after being emitted from the laser output unit 100 may be parallel to the rotation axis of the scanning unit 200. The incident laser beam may fly along the rotation axis of the scanning unit 200.

4 is a diagram illustrating a lidar device according to an exemplary embodiment.

3, the lidar device 1000 may include a laser output unit 100, a scanning unit 200, and a laser receiving unit 300, and the scanning unit 200 is a collimator 210 and a transmission unit. A mirror 220, a reception mirror 230, and a condensing lens 240 may be included. For a description of the operation of each of the above components, refer to FIG. 3, and a detailed description thereof will be omitted.

The reception mirror 230 may rotate based on the rotation axis a.

The laser output unit 100, the collimator 210, the transmission mirror 220, the reception mirror 230, the condensing lens 240, and the laser reception unit 300 may be disposed on the rotation axis a.

The receiving mirror 230 may have a central axis (b). The first reflective area 231 and

The second reflective regions 232 may be symmetrical with respect to the central axis b.

)만큼 경사지도록 배치될 수 있다. 예를 들어, 제3 각도(

)는 45도가 될 수 있다.The receiving mirror 230 may be disposed such that the central axis b is inclined with the rotation axis a. The central axis (b) is the third angle from the rotation axis (a) (

) Can be arranged to be inclined. For example, the third angle (

) Can be 45 degrees.

The receiving mirror 230 may have a predetermined center of gravity. The rotation axis (a) may not pass the center of gravity.

An intersection point between the rotation axis (a) and the central axis (b) may be formed. The intersection point may be located on a virtual line extending one end of the first reflective region 231 and one end of the second reflective region 232.

5 is a diagram for describing a lidar device according to another embodiment.

5, the lidar device 1000 may include a laser output unit 100, a scanning unit 200, and a laser receiving unit 300, and the scanning unit 200 is a collimator 210, a transmission mirror 220, a reception mirror 230 and a condensing lens 240 may be included.

The lidar device 1000 may operate similarly to the lidar device of FIG. 3. Hereinafter, a detailed description thereof will be omitted, and a description will be made focusing on the difference from the lidar device of FIG. 3.

The laser output unit 100 may emit a laser beam in the x-axis direction.

The lidar device 1000 may include a guide mirror 250 for guiding a laser beam emitted from the laser output unit 100 to the transmission mirror 220.

The guide mirror 250 may refract the laser beam emitted along the x-axis direction in the y-axis direction. Accordingly, the laser beam incident on the transmission mirror 220 may fly in the y-axis direction.

The guide mirror 250 may have various shapes. For example, the guide mirror 250 may include a flat mirror surface.

The guide mirror 250 may be disposed on the rotation axis of the scanning unit 200.

The guide mirror 250 may be disposed on an outgoing path of the laser beam emitted from the laser output unit 100. Here, the outgoing light path may mean a laser light path from the laser output unit 100 to the object Ob.

A plurality of guide mirrors 250 may be disposed on the light exit path.

Meanwhile, in the above description, only the guide mirror 250 is disposed on the light exit path, but is not limited thereto, and the guide mirror 250 may be disposed on the light receiving path. Here, the light-receiving path may mean a laser light path from the object Ob to the laser receiving unit 300.

The collimator 210 may generate a parallel beam from the laser beam output from the laser output unit 100.

The collimator 210 may guide the output laser beam to the guide mirror 250.

The collimator 210 may be disposed between the laser output unit 100 and the guide mirror 250.

6 is a perspective view illustrating a LiDAR device according to an exemplary embodiment, and FIG. 7 is a perspective view illustrating a LiDAR device according to an exemplary embodiment.

The LiDAR device according to FIGS. 6 and 7 may operate similarly to the LiDAR device according to FIG. 3. Accordingly, detailed descriptions of portions that overlap with the above descriptions will be omitted.

The transmission mirror 220 and the reception mirror 230 are integrally combined and formed, and may rotate about the same axis.

The receiving mirror 230 may have various shapes. For example, the reception mirror 230 may have a hexahedral shape. Alternatively, the reception mirror 230 may have a truncated cone shape.

The reception mirror 230 may include a hexahedral structure. The structure may have a hexahedral shape with an empty inside. However, the present invention is not limited thereto, and the structure may have other shapes such as a truncated cone and a cylinder.

The structure may include at least one reflective area or reflective mirror. For example, a reflective mirror in a flat plate shape may be formed on the inner surface of the structure.

The first reflective area 231 and the second reflective area 232 may be formed on at least a portion of the inner surface of the structure. The first reflective area 231 may be located in a positive direction of the d-axis. The second reflective area 232 may be located in a negative direction of the d-axis. The d-axis is perpendicular to the c-axis, and the c-axis may coincide with the central axis b of the receiving mirror 230.

The first reflective area 231 and the second reflective area 232 may include a c-axis and may be symmetrical with respect to a virtual plane perpendicular to the d-axis. The first reflective area 231 and the second reflective area 232 may be disposed to face each other.

The laser beam reflected from the object Ob may be reflected at least twice on the inner surface of the structure and then collected by the laser receiver 300. The reflected laser beam may be sequentially reflected in the first reflection area 231 and the second reflection area 232.

The flight path of the laser beam reflected from the object Ob may be changed at least two or more times inside the receiving mirror 230.

Reflective mirrors may be disposed in the first reflective area 231 and the second reflective area 232, respectively. For example, a first reflective mirror may be disposed in the first reflective area 231, and a second reflective mirror may be disposed in the second reflective area 232.

The reflective mirror may have various shapes. For example, the reflective mirror may have a flat plate shape as shown in FIG. 6, and may have a disk shape as shown in FIG. 7, but in addition, the reflective mirror may have a circular shape, It can have various shapes such as square.

The size of the reflection mirror may be related to the size of the condensing lens 240. The size of the reflection mirror may be equal to the size of the condensing lens 240. This is because in order to cover all the size of the condensing lens 240, a reflection mirror having an area corresponding thereto is required. The reflection mirror may receive as many laser beams as possible reflected from the object Ob and transmit them to the condensing lens 240.

8 is a diagram for describing a lidar device according to another embodiment.

The lidar device according to FIG. 8 may operate similarly to the lidar device according to FIG. 3. Accordingly, a detailed description will be omitted for overlapping portions of the above descriptions, and will be described focusing on the differences.

The scanning unit 200 according to an embodiment may include a filter module 260.

The filter module 260 may block components of a partial wavelength band of the optical signal. For example, the filter module 260 may block components in a wavelength band around it except for a 905 nm wavelength. Here, blocking may mean that the strength of the signal after passing through the filter module 260 is reduced to a predetermined range or less compared to the strength of the signal before passing through the filter module 260.

The filter module 260 may have a center wavelength. After passing through the filter module 260, the intensity of the component of the center wavelength band among the components of light may be greater than the intensity of the component of the remaining wavelength band.

The filter module 260 may acquire a laser beam provided from one side. The filter module 260 may lower the intensity of some wavelength components of the obtained laser beam.

The laser output unit 100 may output the first light L1. The first light L1 may have a Gaussian type spectral characteristic. For example, the first light L1 may have a Gaussian spectral characteristic having a center wavelength of 905 nm.

The first light L1 may be reflected by the transmission mirror 220 and then irradiated onto the object Ob.

The receiving mirror 230 or the filter module 260 may acquire the second light L2. The second light L2 may include the first light L1 and noise light. The noise light may include light caused by back-scattering immediately incident to the receiving mirror 230 after the first light L1 is reflected from the inside of the housing or window of the lidar device 1000. have. Alternatively, the noise light is light outside the lidar device 1000 that is not related to the first light L1 and may include sunlight noise.

The filter module 260 may filter the second light L2 at least once or more. Here, the filtering may mean an operation of reducing the intensity of some wavelength components of light, and this may be applied in the same manner below.

For example, the filter module 260 may convert the obtained second light L2 into the third light L3. The third light L3 may be light with reduced noise compared to the second light L2. The third light L3 may have higher frequency or wavelength selectivity than the second light L2. The full width at half maximum (FWHM) of the third light L3 may be smaller than the full width at half maximum of the second light L2.

Accordingly, the wavelength selectivity of light acquired by the laser receiver 300 may increase, and a measurable distance of the lidar device may increase.

The filter module 260 may filter not only light provided from the outside of the receiving mirror 230 but also light provided from the inside of the receiving mirror 230. The filter module 260 may filter light reflected from the inside of the reception mirror 230.

The filter module 260 may convert the third light L3 into the fourth light L4. The fourth light L4 may be obtained from the laser receiver 300. The fourth light L4 may be light with reduced noise compared to the third light L3. The fourth light L4 may have a higher frequency or wavelength selectivity than the third light L3. The full width at half maximum (FWHM) of the fourth light L4 may be smaller than the full width at half maximum of the third light L3. Accordingly, the wavelength selectivity of light acquired by the laser receiver 300 may increase, and a measurable distance of the lidar device may increase.

Meanwhile, the light filtering through the filter module 260 is not necessarily performed twice, and may be performed only once. For example, the filter module 260 alternatively performs an operation of converting the second light L2 into the third light L3 and an operation of converting the third light L3 into the fourth light L4. You may.

The filter module 260 may be disposed between the receiving mirror 230 and the object Ob on the light receiving path. For example, the filter module 260 may be disposed on the receiving mirror 230. The filter module 260 may be integrally formed with the receiving mirror 230. The filter module 260 may be connected to one end of the receiving mirror 230.

The filter module 260 may have various forms. For example, the filter module 260 may include a flat filter surface. Alternatively, the filter module 260 may have a plurality of filter surfaces.

The filter module 260 may be disposed to be inclined with the rotation axis of the receiving mirror 230. For example, the filter module 260 may be disposed to be inclined to the rotation axis by 45 degrees. Accordingly, the laser beam reflected from the object Ob may enter the filter module 260 at an angle of 45 degrees.

The filter module 260 may be disposed to be perpendicular to the central axis of the receiving mirror 230. Alternatively, the filter module 260 may be disposed at an angle of 45 degrees to the laser beam reflected from the transmission mirror 220.

9 is a graph for explaining the effect of the filter module. More specifically, FIG. 9 is a graph showing normalized light intensity according to wavelength.

The first signal s1 has a first full half width w1, the second signal s2 has a second full half width w2, and the third signal s3 has a third full half width w3. I can. The first full half width w1 may be greater than or equal to the second full half width w2, and the second full half width w2 may be greater than or equal to the third full half width w3.

The first to third signals s1, s2, and s3 may have a center wavelength of 905 nm.

The first signal s1 may correspond to the first light L1 or the second light L2 of FIG. 8. The second signal s2 may correspond to the third light L3 of FIG. 8. The third signal s3 may correspond to the fourth light L4 of FIG. 8.

As described above, as the filter module 260 passes, a noise component of light may be reduced. For example, noise lights around a wavelength of 905 nm, which is a central wavelength, may be reduced. The wavelength selectivity of light acquired by the laser receiver 300 increases, and the full width at half maximum may decrease. Accordingly, the measurable distance of the lidar device may increase.

Meanwhile, the center wavelength of the filter module 260 may vary according to the incident angle of light incident on the filter module 260.

10 is a graph showing an example of a change in a center wavelength of a filter module according to an incident angle.

The first graph g1 may represent transmittance of the filter module according to a wavelength when light enters the filter module at a predetermined angle. The second graph g2 may represent transmittance of the filter module according to a wavelength when light enters the filter module at an angle different from the predetermined angle. As shown in FIG. 10, the center wavelength of the filter module may vary according to the angle of incidence of light incident on the filter module.

For example, the predetermined angle may be 45 degrees. In this case, referring to the lidar device of FIG. 8, even if light passes through the filter module twice, all of the light may be incident to the filter module close to 45 degrees. Accordingly, even if the filter module performs the filtering operation twice, there is an effect that significant optical loss does not occur.

On the other hand, when light passes through the filter module twice, when the first incident angle and the second incident angle are different, light loss may occur.

Meanwhile, when noise light is removed by the filter module, a measurable distance of the lidar device may increase. As described above, when the laser receiver detects a laser beam, it may convert an optical signal into an electric signal. In this case, the laser receiver may detect an edge from the electrical signal using a predetermined threshold value, and a laser reception time may be calculated using the detected edge.

For example, as the predetermined threshold value decreases, an optical signal having a small size may be detected, and accordingly, a measurable distance of the lidar device may increase. This may be possible as the noise light is removed.

The laser receiver may amplify the magnitude of the electric signal. In this case, as the amplification ratio increases, an optical signal having a small size can be detected. Accordingly, the measurable distance of the lidar device may increase. Even if the amplification ratio is increased, since noise light is reduced according to the filtering operation of the filter module, detection of noise light as a laser beam can be prevented.

11 is a perspective view showing a LiDAR device according to an embodiment.

The lidar device 1000 may include a housing 500 and a window 600.

The housing 500 may protect the components of the above-described lidar device from external impact.

The housing 500 may have various shapes. For example, the housing 500 may have a hexahedral shape. However, it is not limited thereto and may have various other shapes.

Components such as the above-described laser output unit, scanning unit, laser receiving unit, and control unit may be provided inside the housing 500.

The lidar device 1000 may include a window 600 coupled to the housing 500.

The window 600 may prevent external contaminants such as dust or foreign matter from flowing into the lidar device 1000.

The window 600 may be provided in various shapes and may include a curved surface.

The laser beam output from the laser output unit may pass through the window 600 and then be irradiated to the object. The laser beam reflected from the object may be obtained by the laser receiving mirror after passing through the window 600.

To this end, the window 600 may be made of a transparent material.

The window 600 may include a filter that reduces the intensity of light in a specific wavelength band. For example, the window 600 may include a filter that reduces the intensity of light in the visible light band. The filter may be a coating member coated on the window 600.

In the above, the configuration and features of the present invention have been described based on the embodiments according to the present invention, but the present invention is not limited thereto, and various changes or modifications can be made within the spirit and scope of the present invention. It will be apparent to those skilled in the art, and therefore, such changes or modifications are found to belong to the appended claims.

1000: lidar device
100: laser output unit
200: scanning unit
210: collimator
220: transmitting mirror
230: receiving mirror
231: first reflection area
232: second reflection area
240: condensing lens
250: guide mirror
260: filter module
300: laser receiver
400: control unit
500: housing
600: Windows

Claims (14)

A laser output unit for outputting a laser beam;
A scanning unit that rotates along a rotation axis and reflects the laser beam output from the laser output unit toward an object; And
Includes; a laser receiving unit for receiving the laser beam reflected from the object through the scanning unit,
The scanning unit,
A transmission mirror that reflects the laser beam output from the laser output unit toward an object, and
Acquiring the laser beam reflected from the object, and including a receiving mirror for reflecting toward the laser receiving unit by changing a light receiving path of the obtained laser beam therein,
The receiving mirror includes a first reflection area and a second reflection area,
The first reflection region receives the laser beam reflected from the object, changes the flight path of the received laser beam,
The second reflective area receives a laser beam from the first reflective area, and reflects the received laser beam toward the laser receiver,
The first reflective area and the second reflective area are the receiving mirrors so that the second reflective area receives as many laser beams as possible and reflects the received laser beam toward the light receiving unit. Symmetrical about the central axis of
Lida device.
The method of claim 1,
The transmission mirror rotates 360 degrees based on the rotation axis.
Lida device.
The method of claim 2,
The receiving mirror rotates integrally with the transmitting mirror
Lida device.
The method of claim 2,
Further comprising a condensing lens for guiding the laser beam reflected from the receiving mirror to the laser receiving unit,
The central axis of the condensing lens coincides with the rotation axis
Lida device.
The method of claim 3,
The laser receiver is disposed on the axis of rotation
Lida device.
The method of claim 1,
The first reflection area is disposed to form a first angle with a virtual surface perpendicular to a virtual line extending from a laser beam incident on the transmission mirror after being output from the laser output unit,
The second reflective area is disposed to form a second angle with the virtual surface,
The sum of the first angle and the second angle is 90 degrees
Lida device.
The method of claim 5,
Characterized in that the first angle is greater than at least twice the second angle
Lida device.
The method of claim 2,
The central axis of the receiving mirror is characterized in that inclined 45 degrees with the rotation axis
Lida device.
The method of claim 1,
The receiving mirror is a truncated cone shape
Lida device.
A laser output unit for outputting a laser beam;
A scanning unit that rotates along a rotation axis and reflects the laser beam output from the laser output unit toward an object; And
Includes; a laser receiving unit for receiving the laser beam reflected from the object through the scanning unit,
The scanning unit may include a transmission mirror that reflects the laser beam output from the laser output unit toward the object, and obtains the laser beam reflected from the object, but changes the light receiving path of the obtained laser beam therein to toward the laser receiving unit. A receiving mirror that reflects, and a filter module coupled with the receiving mirror to filter some wavelength components of the laser beam reflected from the object,
The receiving mirror receives a laser beam reflected from the object, and a first reflection area for changing a flight path of the received laser beam, and
And a second reflection area that receives the laser beam from the first reflection area and reflects the received laser beam toward the laser receiving unit.
Lida device.
The method of claim 10,
The filter module filters a partial wavelength component of a laser beam incident to or emitted from the receiving mirror.
Lida device.
The method of claim 10,
The filter module is arranged to be perpendicular to the central axis of the receiving mirror
Lida device.
The method of claim 12,
When the laser beam incident to the filter module is incident at an angle of 45 degrees, the point at which the intensity of the laser beam passing through the filter module becomes maximum is in the 905 nm band.
Lida device.
The method of claim 10,
The full half width (FWHM) of the laser beam output from the laser output unit is greater than the full half width of the laser beam obtained by the laser receiver.
Lida device.

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