WO2017065424A1

WO2017065424A1 - Three-dimensional laser scanning device and three-dimensional laser scanning system comprising same

Info

Publication number: WO2017065424A1
Application number: PCT/KR2016/010739
Authority: WO
Inventors: 문연국; 박호영
Original assignee: 전자부품연구원
Priority date: 2015-10-16
Filing date: 2016-09-26
Publication date: 2017-04-20

Abstract

The present invention relates to a three-dimensional scanning technology using a laser. The present invention comprises: a laser output device for outputting laser light, which is output from a laser light source, at 360° in all directions; and a laser receiver formed on the upper part or the lower part of the laser output device and for receiving laser light reflected by means of an object which is located on the traveling path of the light emitted from the laser output device.

Description

3D laser scanning device and 3D laser scanning system comprising the same

The present invention relates to a three-dimensional scanning technology using a laser, and more particularly, to a three-dimensional laser scanning device capable of scanning a 360-degree omnidirectional direction with a laser light source and a three-dimensional laser scanning system including the same.

Light Detection And Ranging (LIDAR) emits light (e.g., a laser) onto a target object and analyzes the light reflected from the object to determine distance, direction, velocity, temperature, material distribution and concentration characteristics for that object. It is one of the remote detection devices that can be measured. LIDAR takes advantage of lasers that can generate pulse signals with high energy density and short periods, allowing you to more precisely measure the physical properties of objects (such as temperature, mass distribution and concentration characteristics), distance, direction, and speed. have.

LIDAR is used in various fields such as 3D image acquisition, weather observation, object velocity or distance measurement, autonomous driving, etc. using a laser light source having a specific wavelength or a laser light source having a variable wavelength as a light source. For example, LIDAR is installed in aircraft, satellites, etc., and is used for precise atmospheric analysis and global environment observation, and is used as a means for supplementing camera functions such as distance measurement to objects by mounting on spacecraft and exploration robots. In addition, a simple type of LiDAR sensor technology is commercially available on the ground for long-range distance measurement and automobile speed violation enforcement. Recently, it is used as a laser scanner or a 3D video camera, and is used for 3D reverse engineering or driverless cars.

LIDAR of the 3D Laser Scanner type, which is widely used recently, includes a head having a plurality of laser output devices and a plurality of laser sensors, and mechanically rotates the head using a motor. However, this type of LIDAR is expensive because a plurality of laser outputs and a plurality of laser sensors are used, and there is a limit that a view update period is dependent on the rotational speed of the head.

Korean Patent No. 10-1417431 relates to a three-dimensional spatial information generation system using a LIDAR sensor, and is mounted on an outer center of a vehicle wheel to be rotated together with a two-dimensional LIDAR sensor unit, and the rotation angle of the vehicle wheel. It provides a three-dimensional spatial information generation system using a LIDAR sensor comprising a processing unit for generating three-dimensional spatial information by reflecting the angle of measurement and the rotation angle measured by the angle sensor to the two-dimensional information measured by the LIDAR sensor unit. .

An embodiment of the present invention is to provide a three-dimensional laser scanning device capable of scanning 360 degrees omnidirectional with a laser light source and a three-dimensional laser scanning system including the same.

One embodiment of the present invention is to provide a three-dimensional laser scanning device capable of scanning 360 degrees omnidirectional without mechanical rotation and a three-dimensional laser scanning system including the same.

One embodiment of the present invention is to provide a three-dimensional laser scanning device and a three-dimensional laser scanning system including the same that can reduce the production cost without deterioration of performance.

Among the embodiments, the three-dimensional laser scanning device includes a laser output unit for outputting the laser light output from the laser light source in 360 ° direction; And a laser receiver which is formed above or below the laser output unit and receives the laser light reflected by an object located on a traveling path of the light emitted from the laser output unit.

In one embodiment, the laser receiver comprises: a light receiving lens for collecting laser light reflected by the object; And it may include a light receiving unit for receiving the laser light collected through the light receiving lens.

In one embodiment, the light receiving unit may include a light receiving element for converting the laser light into an electrical signal and a readout unit for reading and signal processing an electrical signal from the light receiving element.

In one embodiment, the light receiving element may be a focal plane array of a plurality of light receiving elements.

In one embodiment, the light receiving element may be formed in a cylindrical shape such that the horizontal viewing angle is 360 degrees.

In one embodiment, the light receiving lens may be arranged such that a plurality of light receiving lenses having different sizes may be focused on the light receiving unit.

In one embodiment, the light emitting device may further include a metal line connecting the lead-out part to the light receiving element and the metal line.

In an embodiment, the metal line may include a first metal line connected to the active region and the lead-out of the light receiving element, and a second metal line formed on the active region of the light receiving element.

In an embodiment, the second metal lines may be formed at intervals at which interference of incident light does not occur.

Among the embodiments, the three-dimensional laser scanning system is formed on the laser output unit for outputting the laser light output from the laser light source in 360 ° direction and the upper or lower portion of the laser output, on the traveling path of the light emitted from the laser output It includes a three-dimensional laser scanning device including a laser receiver for receiving the laser light reflected by the object located in the and a computing device for measuring the distance to the object based on the signal received by the three-dimensional laser scanning device. .

In one embodiment, the computing device may measure a distance to the object based on a time of flight (ToF) of the received laser light.

The three-dimensional laser scanning apparatus and the three-dimensional laser scanning system including the same according to an embodiment of the present invention can scan 360 degrees omnidirectional with a laser light source.

The three-dimensional laser scanning apparatus and the three-dimensional laser scanning system including the same according to an embodiment of the present invention can scan 360 degrees omnidirectionally without mechanical rotation, and fundamentally solve the problem of the view update period. I can solve it.

The three-dimensional laser scanning apparatus and the three-dimensional laser scanning system including the same according to an embodiment of the present invention can reduce the manufacturing cost without deterioration of performance.

1 is a view illustrating a three-dimensional laser scanning system according to an embodiment of the present invention.

FIG. 2 is a block diagram illustrating a configuration of a 3D laser scanning apparatus of FIG. 1.

3 illustrates an example of a light receiving unit and a plurality of light receiving lenses.

4 is another example of the light receiving unit and the plurality of light receiving lenses.

5 is a diagram illustrating an embodiment of a light receiving unit.

6 is a view illustrating another embodiment of the light receiving unit.

7 is a view illustrating still another embodiment of the light receiving unit.

8 is a diagram illustrating a focal plane array sensor of a light receiver.

9 is a diagram illustrating a readout circuit of the focal plane array sensor.

10 and 11 illustrate a method of arranging lead-out lines according to an exemplary embodiment of the present invention.

Description of the present invention is only an embodiment for structural or functional description, the scope of the present invention should not be construed as limited by the embodiments described in the text. That is, since the embodiments may be variously modified and may have various forms, the scope of the present invention should be understood to include equivalents capable of realizing the technical idea. In addition, the objects or effects presented in the present invention does not mean that a specific embodiment should include all or only such effects, the scope of the present invention should not be understood as being limited thereby.

On the other hand, the meaning of the terms described in the present application should be understood as follows.

Terms such as "first" and "second" are intended to distinguish one component from another component, and the scope of rights should not be limited by these terms. For example, the first component may be named a second component, and similarly, the second component may also be named a first component.

When a component is referred to as being "connected" to another component, it should be understood that there may be other components in between, although it may be directly connected to the other component. On the other hand, when a component is referred to as being "directly connected" to another component, it should be understood that there is no other component in between. On the other hand, other expressions describing the relationship between the components, such as "between" and "immediately between" or "neighboring to" and "directly neighboring to", should be interpreted as well.

Singular expressions should be understood to include plural expressions unless the context clearly indicates otherwise, and terms such as "comprise" or "have" refer to a feature, number, step, operation, component, part, or feature thereof. It is to be understood that the combination is intended to be present and does not exclude in advance the possibility of the presence or addition of one or more other features or numbers, steps, operations, components, parts or combinations thereof.

In each step, an identification code (e.g., a, b, c, etc.) is used for convenience of description, and the identification code does not describe the order of the steps, and each step clearly indicates a specific order in context. Unless stated otherwise, they may occur out of the order noted. That is, each step may occur in the same order as specified, may be performed substantially simultaneously, or may be performed in the reverse order.

The present invention can be embodied as computer readable code on a computer readable recording medium, and the computer readable recording medium includes all kinds of recording devices in which data can be read by a computer system. . Examples of computer-readable recording media include ROM, RAM, CD-ROM, magnetic tape, floppy disk, optical data storage device, and the like, and are also implemented in the form of a carrier wave (for example, transmission over the Internet). It also includes. The computer readable recording medium can also be distributed over network coupled computer systems so that the computer readable code is stored and executed in a distributed fashion.

All terms used herein have the same meaning as commonly understood by one of ordinary skill in the art unless otherwise defined. Generally, the terms defined in the dictionary used are to be interpreted to coincide with the meanings in the context of the related art, and should not be interpreted as having ideal or excessively formal meanings unless clearly defined in the present application.

Referring to FIG. 1, the 3D laser scanning system 100 includes a 3D laser scanning device 110 and a computing device 120.

The three-dimensional laser scanning device 110 includes an output 112 and a light receiver 114. The 3D laser scanning device 110 outputs laser light in all directions around 360 degrees around the 3D laser scanning device 110, and receives the laser light reflected by the subject 130 located in the vicinity. In one embodiment, the 3D laser scanning device 110 may correspond to LIDAR (Light Detection And Ranging). The 3D laser scanning device 110 generates and transmits an electrical signal corresponding to the received laser light to the computing device 120.

The output unit 112 emits light emitted from the light source in various directions. The output unit 112 emits light emitted from the light source in all directions of 360 °. The output unit 112 diffuses the laser light output from the light source, and passes the diffused laser light from the inside of the cylindrical diffraction grating in the lateral outward direction to be uniformly distributed in the front side of the cylindrical (hollow) diffraction grating. Output a plurality of laser lights. In this case, the diffraction grating is arranged along the circumferential direction, and the light source can be located inside the diffraction grating. The output unit 112 outputs a plurality of laser lights uniformly distributed in all directions around 360 degrees with respect to the three-dimensional laser scanning device 110.

The light receiver 114 is positioned at a predetermined position and receives the laser light reflected by the subject 130 located on the traveling path among the plurality of laser lights output from the output unit 112. That is, the light emitted from the output unit 112 and then reflected by the light receiver 114 is irradiated to the light receiver 114. The light receiver 114 generates an electrical signal corresponding to the received laser light and transmits it to the computing device 120.

The computing device 120 measures the distance between the 3D laser scanning device 110 and the subject 130 based on the signal received from the 3D laser scanning device 110. In one embodiment, the computing device 120 may measure the distance to the subject based on the time of flight (ToF) of the received laser light. In one embodiment, the computing device 120 may measure the direction of the subject 130 based on the signal received by the 3D laser scanning device 110.

Referring to FIG. 2, the three-dimensional laser scanning device 110 includes an output unit 210 and a light receiver 230.

The output unit 310 may include a light source for outputting laser light, a refractive lens and a conical mirror. Light output from the light source is uniformly diffused through the refractive lens and incident on the mirror. Light incident on the conical mirror is emitted in 360 ° forwards. In the present exemplary embodiment, a refractive lens and a conical mirror are used as the optical device emitting 360 ° of light emitted from the light source, but the present invention is not limited thereto.

The laser light output from the output unit 210 is reflected by the

subjects

220a and 220b, and the light receiver 230 receives the laser light reflected by the

subjects

220a and 220b.

The light receiver 230 includes

light receiving lenses

240a and 240b and a light receiving unit 250. The light receiver 250 includes a light receiver and a lead-out unit. The light receiving element may be an optical sensor. The light receiving element may be a photodiode. Light passing through the light receiving lens 240 may be irradiated to the light receiving unit 250.

The light receiving lens collects (collects) the laser light reflected by the

subjects

220a and 220b, and the light receiving unit 250 receives the laser light collected through the

light receiving lenses

240a and 240b. That is, the light passing through the

light receiving lenses

240a and 240b is irradiated to the light receiving unit 250.

In one embodiment, the

light receiving lenses

240a and 240b may be positioned around the light receiving unit 250 so as to receive the laser light from the surrounding 360 degrees of the light receiver 230. According to an embodiment, a plurality of light receiving lenses may be positioned around the light receiving unit 250. Furthermore, the plurality of light receiving lenses 240 may be arranged along the side of the cylinder or taper. In this case, the plurality of light receiving lenses 240 may be arranged along the circumferential direction. It may also be arranged along the axial direction. In addition, the plurality of light receiving lenses 240 may be aligned in a straight line along the circumferential direction and the axial direction. The plurality of light receiving lenses 240 may have different sizes, and may be divided into two or more groups according to the sizes. In this case, the sizes are the same between the light receiving lenses belonging to the same group.

4 to 7 show various embodiments of the light receiver.

The light receiver is composed of a plurality of light receiving lenses 240 and the light receiving unit 250, and may be implemented in various shapes as described below. The light receiver is preferably installed in the vertical form on the top or bottom of the output.

3 illustrates an example of a plurality of light receiving lenses 240 and a cylindrical light receiving unit 250.

Referring to FIG. 3, a plurality of light receiving lenses 240 are disposed around the light receiving unit 250. The light receiving lenses 240 may collect laser light received at a corresponding position and collect the laser light by a sensor of the light receiving unit 250 corresponding to the corresponding position. Lens characteristics (refractive angle, focal length, etc.) of the light receiving lens 240 may be designed so that the laser light may be collected by a sensor of the light receiving unit 250 corresponding to the corresponding position.

The size of the light receiving lens 240 may vary depending on the embodiment. In one embodiment, the light receiving lens may have a size corresponding to the plurality of light receiving elements. For example, when one light receiving lens has a size covering a plurality of sensor regions, the light receiving lens may focus the plurality of light receiving elements.

In another embodiment, the light receiving lens may have a size corresponding to one light receiving element. For example, when one light receiving lens has a size covering an area of one light receiving element, the light receiving lens may condense the light receiving element.

Referring to FIG. 4, a plurality of light receiving lenses 240 having different sizes may be disposed around the light receiving unit 250. For example, first light receiving lenses 272 of a first size may be disposed, and second light receiving lenses 274 of a second size may be disposed between the first light receiving lenses 272. The second light receiving lens 274 may correspond to a light receiving element positioned between the first light receiving lenses 272.

In one embodiment, the first light receiving lens 272 may correspond to the plurality of light receiving elements, and may focus the light on the corresponding plurality of light receiving elements. The second light receiving lens 274 corresponds to one light receiving element, and may focus on the corresponding light receiving element. Lens characteristics (refractive angle, focal length, etc.) of the first light receiving lens 272 and the second light receiving lens 274 may be designed to be focused on the light receiving element of the light receiving unit 250 corresponding to the corresponding position. Can be.

In the case of FIGS. 3 to 4, the cylindrical light-receiving unit has been described as a reference, but the shape of the light-receiving unit may vary according to embodiments.

5 and 6 illustrate examples in which the diameters of the upper and lower surfaces of the light receiver 250 are different.

5 illustrates a case where the diameter of the upper surface of the light receiver 250 is large.

The light receiver may be positioned at a position where laser light reflected from an object can be easily received, and the light receiver may have a form in which light can be easily received.

For example, when the light receiver is located above the output unit, the light receiver 250 may have a diamond shape in which the upper diameter is larger than the lower diameter as shown in FIG. 4A. The light receiving lens 240 is positioned on the side of the cylinder, and the light receiving unit 250 is easily inclined in the downward direction to receive the laser light received from the lower side direction.

FIG. 6 is a diagram illustrating a case where the diameter of the lower surface of the light receiver 250 is large.

When the light receiver is located below the output unit, the light receiver 250 may have a shape of a cylinder having a diamond shape having a lower diameter than a diameter of an upper portion as shown in FIG. 11B. The light receiving lens 240 is positioned at the side of the cylinder, and the light receiving unit 250 is easily inclined in the upper direction to receive the laser light received from the upper side direction.

In another embodiment, the shape of the light receiving unit 250 may have a cylindrical shape having the same diameter as the lower diameter and the upper diameter, and the light receiving lenses 240 may be oriented by control. For example, when the receiver is located at the top of the output, the light receiving lenses 240 are adjusted to face the lower side direction, and when the receiver is located at the bottom of the output, the light receiving lenses 240 face the upper side direction. Can be adjusted to be.

FIG. 7 is a view illustrating a case where the light receiving unit 250 is polygonal in shape, FIG. 7A is a perspective view of FIG. 7B, and FIG. 7B is a plan view, and FIG. 7C is a developed view.

As shown in FIG. 7, the light receiving unit 250 may be formed in a polygon, and in the present embodiment, the case of the octagon is illustrated. Such a polygonal structure can implement a ToF light-receiving element array having a horizontal viewing angle of 360 °. Meanwhile, the plurality of light receiving elements may be arranged along the circumferential direction such that the viewing angle is 360 °. 7 is only one embodiment of such a light receiving element arrangement.

Referring to Fig. 7C, the light receiving elements (photodiodes, PDs) are arranged as if they are lined up tightly. One light receiving element has a circular viewing angle 290. When the light is securely attached in a line, the horizontal viewing angle may cover 360 degrees. Photodiodes are devices that sense laser light and convert it into electrical signals.

The light receiving lens 240 is for securing a horizontal / vertical viewing angle of the ToF sensor, and may be formed on each surface of the light receiving unit 250, and the light receiving unit 250 receives the light collected by the light receiving lens 240. The light receiving element 260 for sensing is formed. A photo diode (PD) may be used as the light receiving element 260, and may be arranged in a focal plane array (FPA).

8 illustrates an example in which the light receiving element 260 is arranged in a focal plane. Hereinafter, for convenience of description, it will be described on the assumption that the light receiving unit 250 is in the form of a cylinder having the same diameter as the lower diameter and the upper portion.

Referring to FIG. 8, the light receiving unit 250 includes a light receiving element array 610 and a lead-out unit 630 arranged in a focal plane.

The light receiving element array 610 includes a light receiving element for converting received light into an electrical signal, and m × n light receiving elements form the light receiving element array 610 in a matrix form. The light receiving element array 610 is electrically connected to the lead-out unit 620 through an interconnect bump 620. As the light receiving element, a sensor or a photodiode may be used.

The lead-out unit 630 reads out an electrical signal from each light receiving element of the light receiving element array 610, processes the signal, and outputs the signal. The lead-out unit 630 may read electrical signals from each sensor in an event-driven manner to the sensors. The signal output from the readout unit 630 may be transmitted to the computing device 120.

9 is a diagram illustrating a detailed circuit configuration of a light receiving unit.

In the light-receiving yarn array, a plurality of light-receiving elements 610 are arranged in a matrix form, and each of the light-receiving elements 610 is electrically connected to the lead-out part 630 through the lead-out line 620. That is, the plurality of readout lines 620 may correspond one-to-one with the plurality of light receiving elements 610. The lead out line may be called a “metal line”.

The readout unit 630 reads an electrical signal from each light receiving device in an event-driven manner.

One lead-out line 620 may be connected to each light receiving element 610, and when an event occurs (for example, when a laser is received by the corresponding sensor), the readout line 620 may read an electrical signal generated by the corresponding sensor. 630).

In the case in which the plurality of light receiving elements 610 are connected to one lead-out line 620, since the electrical signals cannot be read from the plurality of light receiving elements 610 at the same time, the focal plane array sensor may receive a plurality of lasers simultaneously received. Can't recognize light. Therefore, the readout circuit is configured such that one leadout line 620 is connected to each light receiving element 610 so that the focal plane array sensor can recognize a plurality of laser lights simultaneously received. That is, the light receiving element (sensor) and the lead-out line are matched 1: 1.

The readout unit 630 controls reading of electrical signals from the plurality of 610. When an electrical signal is received, the readout unit 630 identifies a sensor on which the electrical signal is received, and transmits the electrical signal to a next signal processing device (for example, an amplifier or an AD converter). The signal processed by the signal processing device (eg, an amplifier or an AD converter, etc.) may be transmitted to the computing device 120.

However, when the lead-out line is laid out in this manner, there is a problem that the volume of the chip becomes large. Since the number of the lead-out lines 620 is to be arranged equal to the number of the light receiving elements 610, there is a problem that the number of metal lines is increased and consequently the volume is increased.

In order to solve this problem, a method of stacking metal lines (lead-out lines) in multiple layers may be considered. However, when the metal lines are stacked in multiple layers, the photo diodes (light receiving elements) do not receive light properly because they are disposed above the photo diodes of the metal lines.

10 and 11 illustrate a method of arranging lead-out lines (metal lines) to solve such a problem. FIG. 10 is a plan view and FIG. 11 is a sectional view.

As shown in FIGS. 10 and 11, the metal line 820 is formed on the photodiode 810 to reduce the space in which the metal line 820 is disposed. To this end, the metal line 820 may include a first line M1 and a second line M2.

An end of the first line M1 is disposed to be electrically connected to the active region 812 and the readout circuit 830 of the photodiode 810, and the second line M2 is disposed above the photodiode 810. Is placed. The first line M1 is electrically connected to the lead-out unit 830 through the first contact 822, and the second line M2 is connected to the first line M1 through the second contact 824. Electrically connected.

In this case, the second lines M1 are arranged at regular intervals, and the intervals vary depending on the wavelength of the laser light. Since the laser light has an inherent wavelength, interference can be prevented by appropriately adjusting the second metal line spacing. That is, the plurality of second lines M2 may be disposed with a gap such that interference does not occur in the light irradiated to the photodiode 810. If the interference does not occur, even if the second metal line is formed on the active region of the photodiode, laser light may be received through the gap between the metal lines.

Although described above with reference to the preferred embodiment of the present application, those skilled in the art various modifications and changes to the present application without departing from the spirit and scope of the invention described in the claims below I can understand that you can.

Claims

An output unit for emitting the light emitted from the light source in all directions of 360 °; And

And a light receiver which emits light reflected from a subject after being emitted from the output device.
The method of claim 1,

The receiver,

A light receiving lens for collecting light reflected from the subject; And

And a light receiving unit to which light transmitted through the light receiving lens is irradiated.
The method of claim 2,

The light receiving lens is a plurality,

A plurality of the light receiving lens is a three-dimensional scanning device is arranged along the side of the cylinder or taper.
The method of claim 3,

The plurality of light-receiving lenses have a different size, three-dimensional scanning device divided into two or more groups according to the size
The method according to any one of claims 2 to 4,

The light receiving unit,

A light receiving element for converting irradiated light into an electrical signal;

And a readout part electrically connected to the light receiving element to process an electrical signal generated by the light receiving element.
The method of claim 5,

The light receiving element is a plurality,

And a plurality of light receiving elements arranged in a focal plane.
The method of claim 6,

And a plurality of the light receiving elements are arranged along the circumferential direction such that the viewing angle is 360 °.
The method according to claim 6 or 7,

The light receiving element and the lead-out unit are electrically connected by a plurality of metal lines.

And a plurality of the metal lines correspond one-to-one with the plurality of light receiving elements.
The method of claim 8,

The metal line,

A first line electrically connected to an active area of the light receiving element and the lead-out part;

And a second line disposed above the active region of the light receiving element and electrically connected to the first line.
The method of claim 9,

The plurality of second lines are arranged with a gap so that interference does not occur to the light irradiated to the light receiving element.
Three-dimensional scanning apparatus; And

A computing device electrically connected to the 3D scanning device to measure a distance to a subject based on the light received from the 3D scanning device,

The three-dimensional scanning device,

An output unit for emitting the light emitted from the light source in all directions of 360 °; And

And a light receiver which emits light reflected from the object after being emitted from the output device.
The method of claim 11,

The computing device is a three-dimensional scanning system for measuring the distance to the subject by the Time of Flight (ToF).