KR102181862B1 - A lidar having a structure in which a light emitting axis and a light receiving axis coincide - Google Patents

Abstract

The present invention relates to a lidar having a structure in which the transmission axis and the light reception axis are matched, and the lidar according to the present invention includes a light source unit that outputs sensing light toward a target, and detects reflected light reflected by the target and incident. It includes a light sensing unit, the light source unit is provided on an upper surface, and an insulating unit provided with the light sensing unit on the lower surface.

Description

A lidar with a structure in which the transmission and reception axes are aligned {A LIDAR HAVING A STRUCTURE IN WHICH A LIGHT EMITTING AXIS AND A LIGHT RECEIVING AXIS COINCIDE}

The present invention relates to a lidar, and relates to a lidar having a structure in which a transmission axis and a light reception axis are coincident.

Recently, in the field of intelligent cars and smart cars, a vehicle's active coping function is required for unexpected situations. In other words, by recognizing the appearance of pedestrians, detecting obstacles outside the range of lighting at dark nights, detecting obstacles due to weakening of headlights in rain, or detecting road damage in advance, etc. It is necessary to check in advance the situation that threatens the safety of pedestrians.

On the other hand, it is installed in the front of the vehicle, and when the vehicle moves based on its own emission light, it checks the object in front and warns the driver in advance, as well as electronic control of the vehicle's data that is the basis for stopping or avoiding the vehicle itself. It transmits to an electronic control unit (ECU), and the ECU performs various control using this data. Acquiring such data is called LiDAR.

In order for a lidar to be used in real life, it must have a simple structure and easy to manufacture, and a lidar with a structure that can be miniaturized is required. In general, the radar is a light transmitting unit that condenses and transmits the sensing light, which is a diffused beam output from the light source unit, as parallel light through a transmitting lens, a light receiving unit that is reflected from the target and detected by the light sensing unit, and deflects the sensing light and the reflected light. Since it includes a rotating mirror and an optical system having a focal length, there are limitations in simplifying the structure of the lidar to make it easier or downsizing.

The prior art described in Korean Patent Application 10-2015-0039267 includes a light source that generates light, a rotating mirror that reflects the source light forward, and reflects the light reflected from the target to the light detection unit at a position opposite to the rotating mirror. It includes a reception mirror and a light detector for detecting received light.

The prior art includes a structure in which the transmission axis of the source light from the rotating mirror to the target and the receiving axis of the reflected light from the target to the receiving mirror partially coincide.

However, in the prior art, since the transmission axis of the source light from the light source to the rotating mirror and the light receiving axis of the reflected light from the receiving mirror to the light detection unit are not coincident, the lidar cross-sectional area between the light source and the rotating mirror can be reduced. none. In addition, the conventional technology is not easy to manufacture because the light source unit and the light detection unit are mounted on each insulating unit or on each circuit board, and a rotating mirror and a receiving mirror that deflect the transmission axis and the light receiving axis must be arranged according to the position.

As conceived to solve the above-described problem, an object of the present invention is to provide a lidar having a structure in which a transmission axis and a light reception axis are matched.

In order to achieve the above object, the lidar according to an embodiment of the present invention is a lidar having a structure in which a transmission axis and a reception axis are coincident, comprising: a light source unit for outputting sensing light toward a target; A light sensing unit for sensing reflected light reflected by the target; And a lidar having a structure in which a light transmitting axis and a light receiving axis are matched, including an insulating unit provided with the light source unit on an upper surface and the light sensing unit on a lower surface.

In addition, in an embodiment, a concave mirror provided below the light sensing unit may further include a concave mirror for condensing the reflected light to the light sensing unit.

In addition, in an exemplary embodiment, the insulating portion may have a bar shape, the light source portion may be provided on an upper surface of the insulating portion, and the light sensing portion may be provided on a lower surface of the insulating portion.

In addition, in an embodiment, the other end of the insulating part may be connected and fixed by the housing.

In addition, in an embodiment, an internal reflection blocking tube may be further included that surrounds the light source and protrudes for a predetermined length in a tube shape along a path of the sensing light.

In addition, in an embodiment, a transmission lens may be provided in the internal reflection blocking tube.

In addition, in an embodiment, a rotating mirror is provided to be inclined above the light source unit to deflect the sensing light and the reflected light, and the rotating mirror

In addition, in an embodiment, the light source unit includes a plurality of diodes generating pulsed laser light having different frequencies, and based on external humidity, any one of a plurality of diodes generating pulsed laser light having different frequencies A diode that generates pulsed laser light having one frequency may be selectively driven.

Also, in an embodiment, the output of the light source unit may be increased based on the external humidity.

In addition, in an exemplary embodiment, the insulating unit includes a humidity unit for measuring the external humidity, and has a structure in which the transmitting axis and the receiving axis are coincident.

According to an embodiment of the present invention, since the light source unit and the light sensing unit are provided on the upper and rear surfaces of the insulating unit with the insulating unit therebetween, a position correction operation for matching the transmission axis and the light receiving axis is not required. It is easy to manufacture because the light sensing part is fixed.

According to an exemplary embodiment of the present invention, since the optical axis of the sensing light output from the light source unit is overlapped with the optical axis of the reflected light reflected by the target and incident, the volume of the lidar can be reduced by the size of the overlapped optical axis.

1 is a perspective cross-sectional view of a lidar according to an embodiment of the present invention.
FIG. 2 is a partial cross-sectional view of the lidar shown in FIG. 1.
FIG. 3 is a diagram showing a path of sensing light in the lidar shown in FIG. 1.
FIG. 4 is a view showing an optical axis cross section in a direction A-A' and an optical axis cross section in a B-B' direction in FIG. 3.
FIG. 5 is a diagram schematically illustrating a configuration provided in the insulating part shown in FIG. 1.

Hereinafter, exemplary embodiments disclosed in the present specification will be described in detail with reference to the accompanying drawings, but identical or similar elements are denoted by the same reference numerals regardless of reference numerals, and redundant descriptions thereof will be omitted. The suffixes "module" and "unit" for components used in the following description are given or used interchangeably in consideration of only the ease of preparation of the specification, and do not have meanings or roles that are distinguished from each other by themselves.

In addition, in describing the embodiments disclosed in the present specification, when it is determined that a detailed description of related known technologies may obscure the subject matter of the embodiments disclosed in the present specification, the detailed description thereof will be omitted. In addition, the accompanying drawings are for easy understanding of the embodiments disclosed in the present specification, and the technical idea disclosed in the present specification is not limited by the accompanying drawings, and all modifications included in the spirit and scope of the present invention It should be understood to include equivalents or substitutes.

When a component is referred to as being "connected" or "connected" to another component, it is understood that it may be directly connected or connected to the other component, but other components may exist in the middle. Should be. On the other hand, when a component is referred to as being "directly connected" or "directly connected" to another component, it should be understood that there is no other component in the middle.

Singular expressions include plural expressions unless the context clearly indicates otherwise. In the present application, terms such as "comprises" or "have" are intended to designate the presence of features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, but one or more other features. It is to be understood that the presence or addition of elements or numbers, steps, actions, components, parts, or combinations thereof, does not preclude in advance.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the drawings. It is obvious to those skilled in the art that the present invention can be embodied in other specific forms without departing from the spirit and essential features of the present invention.

Hereinafter, a lidar according to an embodiment of the present invention will be described with reference to FIGS. 1 to 4.

1 is a perspective cross-sectional view of a lidar according to an embodiment of the present invention, and FIG. 2 is a partial cross-sectional view of the lidar shown in FIG. 1.

1 and 2, the lidar 10 includes a light transmitting unit 100, a light receiving unit 200, a rotating mirror unit 300, an insulating unit 340, and a housing 400.

The transmitting unit 100 includes a light source unit 110 that outputs sensing light and a transmitting lens 120 that collects sensing light (SL) so that it is not radiated.

The light source unit 110 may be composed of a laser diode or the like that emits a pulsed laser. In addition, the light source unit 110 may be composed of a plurality of diodes emitting pulsed lasers of different frequencies.

The sensing light SL, which is a pulsed laser generated by the light source unit 110, is output toward the target. In an embodiment of the present invention, the sensing light SL generated by the light source unit 110 is output in the target direction through the rotating mirror 310.

The light source unit 110 is provided in the insulating unit 340. Power supplied from a separate power supply may be supplied through the insulating unit 320 or may be supplied directly from the insulating unit 320.

An internal reflection blocking tube 130 may be provided around the light source unit 110. The internal reflection blocking tube 130 surrounds the light source unit 110 and protrudes for a predetermined length in a tube shape along the path of the sensing light SL, and covers a partial path of the sensing light.

The internal reflection blocking tube 130 may be made of a reflective material or a light absorbing material. When the internal reflection blocking tube 130 is made of a light absorbing material, the sensing light SL reflected from the cover part 410 is blocked by the internal reflection blocking tube 130, so that the reflected sensing light SL is It is possible to prevent misunderstanding as reflected light reflected from the target and incident.

The internal reflection blocking pipe 130 may be a cylindrical shape having the same diameter at one end and the other end in the longitudinal direction. Meanwhile, the diameter sizes at one end and the other end of the internal reflection blocking pipe 130 may be formed differently from each other, and the cross section of the internal reflection blocking pipe 130 may be formed in a polygonal shape.

In particular, it is preferable that the cross-sectional area of the internal reflection blocking pipe 130 is provided in a form that increases as it goes upward. This structure can effectively prevent the sensing light reflected inside the cover from proceeding to the light sensing unit when the sensing light does not pass through the cover unit and internal reflection occurs.

The transmitting lens 120 is provided in the internal reflection blocking tube 130 and condenses the sensing light SL generated and radiated from the light source unit 110 to form parallel light. A plurality of tube lenses 120 may be provided in the internal reflection blocking tube 130, and the plurality of tube lenses 120 may increase the condensing efficiency of the sensing light SL.

The light receiving unit 200 includes a light sensing unit 210 for sensing the reflected light RL and a concave mirror 220 for condensing the reflected light RL to the light sensing unit 210.

The light sensing unit 210 is provided on a lower surface of the insulating unit 340 to detect reflected light (RL) that is reflected from the target and incident through the rotating mirror 310.

The concave mirror 220 condenses the reflected light RL to the light sensing unit 210 using a concave hemispherical reflective surface. The concave mirror 220 has a reflective surface in the concave portion. In addition, the concave mirror 220 is disposed so that a focus is formed on the light sensing unit 210.

The concave mirror 200 may support the edge of the insulating part 340. When the insulating part 340 has a bar shape, one end of the insulating part 340 may be supported by a side end of the concave mirror 200.

The rotating mirror 310 is provided to be inclined above the light source unit 110 to deflect the sensing light SL and the reflected light RL. Specifically, the sensing light SL output from the light transmitting unit 100 is deflected toward the target, and the reflected light RL reflected from the target and incident is deflected toward the light receiving unit 200.

The rotating mirror 310 is connected to the mirror connection part 320 and is rotated by rotational driving of the rotating motor 330. Accordingly, the lidar can output the sensing light SL within the rotation driving range of the rotating mirror and detect the reflected light RL reflected from the target and returned.

The housing 400 forms the exterior of the lidar 10. The housing 400 includes a body 420 supporting an internal structure and a light-transmitting cover part 410.

The body 420 supports internal components including the transmitting unit 100, the light receiving unit 200, and the rotating mirror unit 300, and blocks external foreign substances from flowing into the lidar.

Since the body 420 is made of a material that is not light-transmitting, it is possible to block the inflow of light other than the reflected light. Unlike this, when the body 420 is made of a light-transmitting material, the body 420 may be integrally formed with the cover part 410.

The body 420 has a hollow part on the path of the sensing light SL and the reflected light RL, and the cover part 410 is coupled to the hollow part. In addition, the body 420 may have an upper portion and a lower portion formed separately, and a cover portion 410 may be coupled between the upper portion and the lower portion of the body 420.

The body 420 may be formed in a cylindrical shape having the same upper and lower surfaces. In addition, the body 420 may have different areas of the upper and lower surfaces, and the upper and lower surfaces may have a polygonal shape rather than a circular shape.

The cover part 410 is located on the path of the sensing light SL and the reflected light RL, and covers a part of the body part, that is, a hollow part, to block the inflow of foreign substances. Since the cover part 410 is made of a light-transmitting material, it may transmit the sensing light SL and the reflected light RL.

An internal reflection blocking plate 500 may be provided adjacent to the inner peripheral surface of the cover part 410. The internal reflection blocking plate 500 may be supported by the body 420 and provided adjacent to the inner circumferential surface of the cover part 410. In addition, the internal reflection blocking plate 500 may be integrally formed with the cover part 410. When the internal reflection blocking plate 500 is formed integrally with the cover part 410, the upper and lower surfaces of the internal reflection blocking plate 500 are coated with a material of a light absorbing material or a sticker or tape made of a light absorbing material is attached. I can.

The internal reflection blocking plate 500 is provided in a plate shape along the periphery of the inner peripheral surface of the cover part 410. The sensing light SL reflected upward or downward by the inner circumferential surface of the cover part 410 is blocked. The internal reflection blocking plate 500 may be plural. When there are a plurality of internal reflection blocking plates 500, the plurality of internal reflection blocking plates 500 may include an upper internal reflection blocking plate 510 and a lower internal reflection blocking plate 520.

The upper internal reflection blocking plate 510 is provided adjacent to the inner circumferential surface of the cover part 510 and is provided on the path of the sensing light, that is, the transmission path, and is reflected upwards by the cover part 410 ( SL) is blocked. In addition, the lower internal reflection blocking plate 520 is provided adjacent to the inner circumferential surface of the cover part 510, and is provided under the progress path of the sensing light SL to receive sensing light reflected downward by the cover part 410. Block.

The insulating unit 340 includes a light source unit 110 on an upper surface and a light sensing unit 210 on a lower surface.

The insulating part 340 may be formed of a circuit board or a printed circuit board. The light source unit 110 and the light sensing unit 210 are disposed on the insulating unit 340 so that the center of the light source unit 110 and the center of the light sensing unit 210 are aligned with the insulating unit 340 interposed therebetween. The transmission axis, which is the optical axis, and the light-receiving axis, which is the optical axis of reflected light can be matched.

That is, the light source unit 110 and the light sensing unit 210 disposed on the insulating unit 340 may be modularized so that the transmission axis and the light receiving axis are aligned. In manufacturing a lidar having a structure in which the transmission axis and the light reception axis are matched, the lidar 10 according to the embodiment of the present invention does not require an alignment operation to match the transmission axis and the reception axis, so assembly is easy. .

The insulating part 340 may have a bar shape. The width of the bar-shaped insulating portion 340 may be configured to have a size such that the light source unit 110 and the light sensing unit 210 can be provided on the upper and lower surfaces, and the length of the insulating unit 340 is a concave mirror 220 ) From the center portion, which is the focal portion, may be connected to the side wall portion of the housing 400 or the side wall portion of the concave mirror 220 to be fixed.

When the insulating part 340 has a bar shape having a length, a light source unit 110 is provided on an upper surface of one end of the insulating part 340, and a light sensing part 210 is provided on a lower surface of one end of the insulating part 340. ) Is provided, and the other end of the insulating part 340 may be connected to the housing 400 or the concave mirror 220.

The insulating part 340 is made of a material that is not light-transmitting, so that the sensing light SL generated by the light source unit 110 provided on the upper surface of the insulating part 340 is light provided on the lower surface of the insulating part 340. It prevents proceeding to the sensing unit 210.

In the insulating part 340, a heat dissipating pattern made of a thermally conductive material or a heat dissipating member may be provided at a portion that does not interfere with the wiring formed in the insulating part 340. For example, the bar-shaped insulating part 340 may include a heat dissipating pattern or a heat dissipating member formed in the longitudinal direction of the insulating part 340 in a range that does not block reflected light reflected from the target and incident thereon.

The heat dissipation pattern or the heat dissipation member diffuses heat generated in the light source unit 110 and the light sensing unit 210 to the surroundings, thereby preventing damage to the light source unit 110 and the light sensing unit 210 due to heat.

By disposing the light source unit 110 on the upper surface of the insulating unit 340 and placing the light sensing unit 210 on the lower surface of the insulating unit 340 so as to correspond to the position of the light source unit 110, sensing light SL It is easy to match the transmitting axis of) and the receiving axis of the reflected light (RL), and there is no need for a separate position correction operation for matching the transmitting axis and the receiving axis.

A path of light in the lidar according to an embodiment of the present invention will be described with reference to FIGS. 3 and 4.

3 is a view showing a path of light in the lidar shown in FIG. 1, and FIG. 4 is a view showing an optical axis cross-section in the direction A-A' and an optical axis cross-section in the direction B-B' in FIG. 3 to be.

The sensing light SL is generated by the light source unit 110 and is deflected by the rotating mirror 310 and is output in the target direction through the cover unit 410.

Referring to the optical axis cross-section of A-A' of FIG. 4, the center of the light-receiving axis of the reflected light RL coincides with the center of the transmission axis of the sensing light SL, and the cross-section of the optical axis of B-B' of FIG. 4 is A- It has the same shape as the cross section of the optical axis of A'. That is, as shown in FIG. 4, it can be seen that the light-receiving axis and the light-transmitting axis are identical.

FIG. 5 is a diagram schematically illustrating a configuration provided in the insulating part shown in FIG. 1.

The light source unit 110 provided with a diode generating a pulsed laser outputs a pulsed laser, which is a sensing light, to the rotating mirror 310. Further, the light receiving unit 210 detects reflected light reflected from the target and incident thereon.

The control unit 710 controls components including the light source unit 110, the light receiving unit 210, and the power supply unit 720. The control unit 710 may be located on the insulating unit 340 or outside the insulating unit 340.

The power supply unit 720 supplies power to components including the light source unit 110, the light receiving unit 210, and the power supply unit 720. The power supply unit 720 may be located on the insulating unit 340 or outside the insulating unit 340.

The communication unit 740 is connected to a communication unit of a transportation means such as a vehicle, a ship, and an aircraft equipped with the lidar 10 to transmit and receive control signals from the control unit 710.

The humidity unit 730 is provided in the insulation unit 340 and measures humidity. When a humidity measuring means capable of measuring humidity is separately provided inside the vehicle, the controller 710 may receive humidity information measured by the vehicle through the communication unit 740.

The controller 710 controls the overall operation of the lidar 10, and the power supply unit 720 supplies power to a component or element driven in the lidar 10.

The amount of reflected light detected by the light sensing unit 210 is less than the set amount of light or less than the average amount of light for a certain period of time, the humidity measured from the humidity unit 710 exceeds the set humidity, or transmitted from the transportation means. When the received humidity exceeds the set humidity, the control unit 710 may control to increase the output of the light source unit 110.

Alternatively, when a plurality of diodes having different frequencies of laser pulses are provided in the light source unit 110, when the amount of light detected by the light sensing unit 210 becomes smaller than the set amount of light or less than the average amount of light for a certain period, the control unit ( The 710 may individually drive a plurality of diodes of different frequencies to drive only diodes having a relatively large amount of light reaching the light sensing unit 210.

Since the degree of refraction or scattering of the pulsed laser light is different depending on the frequency, in the case of a weather where the pulsed laser light is easily scattered by water vapor particles due to high humidity, the output of the light source unit 110 is increased or have different frequencies. By using any one of a plurality of diodes generating pulsed laser light, the amount of reflected light reaching the light sensing unit 210 may be increased.

So far, exemplary embodiments have been described and shown in the accompanying drawings to aid in understanding the present invention. However, it should be understood that these examples are for illustrative purposes only and are not limiting. And it should be understood that the invention is not limited to the illustrated and described description. This is because various other modifications can occur to those of ordinary skill in the art.

100: transmitting unit 110: light source unit
120: transmitting lens 130: internal reflection blocking tube
200: light receiving unit 210: light sensing unit
220: concave mirror 300: rotating mirror unit
310: rotating mirror 320: mirror connection
330: rotary motor 340: insulation
400: housing 410: cover
420: body 710: control unit
720: power supply unit 730: humidity unit
740: Ministry of Communications

Claims (10)

In a lidar having a structure in which the transmission axis and the reception axis are aligned,
A light source unit that outputs sensing light toward the target;
A light sensing unit for sensing reflected light reflected by the target; And
It has a structure in which the transmission axis including the insulating part and the light reception axis are matched,
The insulating part is in the form of a bar,
The light source unit is provided on an upper surface of one end of the insulation unit,
The light sensing part is provided on one end of the lower surface of the insulating part,
The light source unit includes a plurality of diodes generating pulsed laser light having different frequencies,
The transmission axis and the reception axis, characterized in that a diode generating pulsed laser light having any one frequency among a plurality of diodes generating pulsed laser light having different frequencies, is selectively driven based on the external humidity. Lida with a matched structure. The method of claim 1,
The light-transmitting axis and the light-receiving axis are aligned with each other, further comprising a concave mirror provided under the light sensing unit and condensing the reflected light to the light sensing unit. delete The method of claim 1,
The other end of the insulating part is a liner having a structure in which the transmission axis and the light reception axis are aligned with each other and fixed by a housing. The method of claim 1,
A light-transmitting axis and a light-receiving axis are aligned with each other, further comprising an internal reflection blocking tube which is formed to protrude in the shape of a tube along a path of the sensing light surrounding the light source unit. The method of claim 5,
A light-transmitting lens and a light-receiving axis are arranged in the internal reflection blocking tube. The method of claim 2,
A rotating mirror provided inclined above the light source unit to deflect the sensing light and the reflected light,
It is provided on the upper portion of the rotating mirror, and further comprises a driving unit for rotating the rotating mirror, characterized in that it has a structure in which the transmission axis and the light receiving axis are matched. delete The method of claim 1,
A light-transmitting axis and a light-receiving axis are aligned with each other, wherein the output of the light source is controlled based on external humidity. The method according to any one of claims 1 and 9,
The insulating part includes a humidity part for measuring the external humidity, and has a structure in which the transmission axis and the light receiving axis are matched.

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