KR20170051663A - Three dimensional scanning system - Google Patents

Abstract

In the present invention, a multi-point output light in the form of a dot line, which is not a solid line, is emitted and then the reflected light reflected from the target is detected by a light receiving module which is an optical detector in the form of a line array, The present invention relates to a three-dimensional scanning system capable of obtaining a high-quality image by increasing the density of light received per unit scanning pixel while using a low-power light source by reducing the output of a light source of a light receiving module.
The three-dimensional scanning system according to the present invention includes an optical transmission module including a light splitting part for splitting the short-point incident light into the multi-point output light and a light scanning part for scanning the multi-point output light divided by the light splitting part in a predetermined viewing angle, A light receiving module for receiving the reflected light reflected from the target after being emitted from the optical transmitting module, and a controller for generating an image of the target based on the reflected light received by the light receiving module.

Description

[0001] THREE DIMENSIONAL SCANNING SYSTEM [0002]

The present invention relates to a three-dimensional scanning system, and more particularly, to a three-dimensional scanning system in which an optical transmission module and a light receiving module are arranged such that the optical axis of output light emitted from the optical transmission module and the optical axis of reflected light received by the optical reception module are in the same direction The present invention relates to a three-dimensional scanning system capable of reducing the weight of the entire apparatus and reducing the manufacturing cost by simplifying the configuration of the apparatus so that it can be compactly implemented.

A three-dimensional image sensor, called LIDAR (Light Detection And Ranging) or LADAR (Laser Detection And Ranging), emits pulsed laser light toward a target, ), And converts it into an electrical signal, whereby the distance to the target and the moving speed of the target can be calculated.

Such a lidar system is widely applied in a variety of fields such as a sensor for detecting obstacles in front of a robot and an unmanned vehicle, a radar gun for speed measurement, an aerial geo-mapping device, a three-dimensional ground survey, and an underwater scanning.

In recent years, the Raida system has been used as a driving assistant application, which allows the driver to be alerted or to take measures to automatically adjust the speed of the vehicle in the event of a dangerous situation such as a frontal or lateral obstacle, The application field of the automatic operation device is expanding.

As an example of the above-described Lada system, a three-dimensional scanning system and a three-dimensional image acquisition method using the same are disclosed in Japanese Patent Application No. 10-1357051 filed and filed by the present applicant.

The three-dimensional scanning system includes a light source device for generating a pulsed laser beam, a scanning system for obtaining a three-dimensional image by calculating a distance of a target by receiving reflected light reflected from a target after emitting pulse light, An optical transmission / reception unit including an optical transmission / reception module for emitting light and receiving reflection of the emitted pulsed laser light; a rotation drive device for rotating the optical transmission / reception means; and a control unit for controlling the light source device, the optical transmission / reception means, Receiving module, wherein the optical transmitting and receiving unit is composed of two or more optical transmitting and receiving modules, and at least one of the two or more optical transmitting and receiving modules is configured to be different from the optical transmitting and receiving module of another optical transmitting and receiving module.

The above-mentioned three-dimensional scanning system has a structure in which both a pulse laser source module and an optical transmitting / receiving means are mounted on a rotary driving device and rotated, and the weight of a pulsed laser source module and a cooling structure for cooling the same A large rotating motor is required, which results in a problem of increasing the weight and volume of the scanning system.

In order to obtain a high level of scanning information at a distance of several tens of meters or a few hundreds of meters using a solid line line laser, the source of the laser pulse light used should be several hundred watts to several thousands of watts or more. In order to generate a laser beam, there is a problem that the size and weight of a light source device as a laser source is increased and the amount of consumed power is large. Accordingly, a large amount of heat is generated,

Also, since the optical axis of the output light emitted from the optical transmitting module and the optical axis of the reflected light received by the optical receiving module are not aligned with each other, the configuration of the device is increased. There is a problem that the precision according to the present invention is somewhat deteriorated.

Korean Registered Patent No. 10-1357051 (Registration date 2014.01.23)

SUMMARY OF THE INVENTION An object of the present invention to solve the above problems is to provide an optical transmitter module and an optical receiver module such that the optical axis of the output light emitted from the optical transmitter module and the optical axis of the reflected light received by the optical receiver module are in the same direction. The present invention provides a three-dimensional scanning system capable of reducing the weight of the entire apparatus, reducing the manufacturing cost, and improving the precision by simplifying the apparatus configuration and compactly implementing the apparatus.

It is still another object of the present invention to provide a light receiving module which is capable of outputting multi-point output light in the form of a dot line, which is not a solid line, Dimensional point cloud data image to form a three-dimensional point cloud data image. Thus, a three-dimensional scanning system capable of obtaining a high-quality image by increasing the density of light received per unit scanning pixel while using a low- .

According to an aspect of the present invention, there is provided a three-dimensional scanning system including a light dividing unit dividing an incoherent incident light into a plurality of output light beams, and a light scanning unit scanning the plurality of output light beams divided by the light splitting unit into a predetermined angle of view An optical transmission module including the optical transmission module; A light receiving module for receiving the reflected light reflected from the target after being emitted from the optical transmitting module; And a controller for generating an image of the target based on the reflected light received by the light receiving module.

Preferably, the light splitting unit may be configured to divide the short-point incident light into a multi-point output light in the form of a dot line extending at a predetermined angle.

Preferably, the optical scanning unit may be configured to reflect the multi-point output light of the dot line shape in a direction perpendicular to the multi-point output light of the dot line shape at a predetermined range angle.

Preferably, the optical scanning unit may be formed of a resonant mirror.

Preferably, the light dividing unit may be configured to divide the short point incident light into the multipoint output light through the diffraction optical filter having the diffraction pattern formed therein.

Preferably, the light dividing unit includes: a collimator for aligning the optical axis of the short point incident light provided from the light source; An incident light reflecting member for changing the path of the short point incident light whose optical axis is aligned by the collimator; And a diffraction optical filter disposed on the path of the short point incident light reflected by the incident light reflecting member and dividing the short point incident light into the dot point type output light as passing the short point incident light, The optical transmission unit is arranged on a path of a dot-shaped multi-point output light divided by the diffraction optical filter, and outputs the multi-point output light of the dot line form in a direction perpendicular to the multi-point output light of the dot- And a resonance type mirror for reflecting the light to the light source.

Preferably, the reflected light reflected from the target after being emitted from the optical transmission module and received by the light receiving module is reflected by the resonant mirror and is primarily switched, and the reflected light reflected by the resonant mirror The path may be secondarily switched by the reflected light reflecting member disposed on the path of the light receiving module and received by the light receiving module.

Preferably, a through-hole for passing the multi-point output light in the form of a dot line divided by the diffraction optical filter may be formed on the center side of the reflection light reflecting member.

Preferably, the light splitting unit includes a light switching housing formed in a square shape and having a through hole formed therein; And a mirror holder having one end provided at one end of the light switching housing and having an inclined portion at the other end, wherein the collimator is provided at the other end of the light switching housing, Shaped through hole formed in the inside of the housing, and the reflected light reflecting member may be provided on an inclined portion of the mirror holder.

The optical transmitter module and the optical receiver module are arranged such that the optical axis of the output light emitted from the optical transmitter module and the optical axis of the reflected light received by the optical receiver module are in the same direction, It is advantageous in that it can be implemented compactly, thereby remarkably reducing the weight of the entire device and reducing manufacturing cost.

In addition, after emitting multi-point output light in the form of a dot line, which is not a solid line, reflected light that is reflected from the target is detected by a light receiving module, which is an optical detector in the form of a line array, As the image is formed, the output of the light source is reduced, and the density of light received per unit scanning pixel is increased while using a low output light source, thereby obtaining a high-level image.

In addition, a variety of dot lines such as an 8-dot line, a 16-dot line, and a 32-dot line can be selected by a simple method of changing the diffraction pattern of the diffraction optical filter, Dimensional scanning sensor can be easily adjusted so that it can be easily changed according to the vertical precision requirement of the 3D scanning sensor.

1 is a perspective view illustrating a three-dimensional scanning system according to an embodiment of the present invention.
2 is a cross-sectional view illustrating a three-dimensional scanning system according to an exemplary embodiment of the present invention.
3 is a partially exploded perspective view showing a three-dimensional scanning system according to an embodiment of the present invention.
4 is a view illustrating a path through which light is emitted through a three-dimensional scanning system according to an embodiment of the present invention.
5 is a diagram illustrating a path through which light is received through a three-dimensional scanning system according to an embodiment of the present invention.
FIG. 6 is a diagram illustrating a DOE mask pattern (15 mm X 15 mm size) structure.
Figs. 7 and 8 are diagrams illustrating that the short-point incident light is divided into the multiple-point incident light by the diffraction optical filter.
9 is a diagram illustrating the distribution of the multi-point dot line light.

The present invention may be embodied in many other forms without departing from its spirit or essential characteristics. Accordingly, the embodiments of the present invention are to be considered in all respects as merely illustrative and not restrictive.

The terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms.

The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component.

And / or < / RTI > includes any combination of a plurality of related listed items or any of a plurality of related listed items.

It is to be understood that when an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, .

On the other hand, when an element is referred to as being "directly connected" or "directly connected" to another element, it should be understood that there are no other elements in between.

The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise.

In the present application, the terms "comprises", "having", "having", and the like are intended to specify the presence of stated features, integers, steps, operations, components, Steps, operations, elements, components, or combinations of elements, numbers, steps, operations, components, parts, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

Terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning consistent with the contextual meaning of the related art and are to be interpreted as either ideal or overly formal in the sense of the present application Do not.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings, wherein like or corresponding elements are denoted by the same reference numerals, and a duplicate description thereof will be omitted.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

A three-dimensional scanning system according to an embodiment of the present invention is a system for acquiring a three-dimensional image by emitting pulse laser light in a predetermined viewing angle shape, receiving reflected light reflected from a target to calculate a distance of a target, The optical transmitter module 100, the optical receiver module 200, and the controller 300, as shown in FIGS. 1 and 2.

The three-dimensional scanning system of the present embodiment is a driving assistant application that can alert the driver or automatically take measures to adjust the speed of the vehicle when a dangerous situation occurs due to an obstacle on the front or side, And the like.

First, the optical transmission module 100 will be described.

The optical transmission module 100 is a part that emits pulsed laser light for three-dimensional scanning, and includes a light splitting part 110 and a light scanning part 120, as shown in FIG.

The light splitting unit 110 is a part for dividing the short-point incident light (L1, pulsed laser light) provided from a light source (not shown), and has an optical axis of the short point incident light L1 provided from a light source such as a laser diode And may be configured to be divided into multi-point output light L2.

Specifically, the light splitting unit 110 includes a collimator 111 for aligning the optical axis of the short-point incident light L1 provided from the light source, a switch for switching the path of the short-axis incident light L1 in which the optical axis is aligned by the collimator 111 Is disposed on the path of the short point incident light L1 reflected by the incident light reflecting member 112 and passes the short point incident light L1 through the multi point output And a diffraction optical filter 113 for splitting the light L2 into light L2.

The light splitting unit 110 is formed in the shape of a letter so that the collimator 111, the incident light reflecting member 112 and the diffraction optical filter 113 can be arranged in the above-described relationship. A light switch housing 115 having a through hole 115h formed therein and a mirror holder 116 having one end at one end of the light switch housing 115 and a slope at the other end, A fixing frame m3 for mounting the holder housing m1 and m2 for mounting the optical filter 113 and the reflection mirror 210 on the inclined portion of the mirror holder 116,

That is, the collimator 111 provided at the other end of the light switching housing 115 receives the short point incident light L1 provided from the light source and aligns the optical axis, transmits the light to the incident light reflecting member 112, The incident light reflecting member 112 provided at the corner of the L-shaped through hole 115h formed in the inside of the switching housing 115 reflects the point of incidence light L1 to approximately 90 degrees and is directed toward the diffractive optical filter 113 And the diffraction optical filter 113 divides the abrupt incident light L1 into a plurality of point output lights L2 and transmits the same through the slit hole 116h formed in the mirror holder 116 to the optical scanning unit 120 .

6, the diffraction optical filter 113 is a filter for diffraction of light formed by a diffraction pattern. The diffraction optical filter 113 diffracts the short-point incident light L1 transmitted from the collimator 111 at a predetermined angle And is divided into multi-point output light (L2) in the form of an opened dot line.

For example, the diffraction optical filter 113 may be formed by etching a mask pattern of a DOE (Diffractive Optical Element) through a photolithography process on a quartz or fused silica wafer material, (L2), and as shown in FIGS. 7 and 8, when the diffracting pattern is applied in various ways, the light having the shortest incident point L1 incident on the diffraction optical filter 113 is divided into 8 dots Point output light L2 of various numbers of dot lines such as lines, 16-dot lines, and 32-dot lines, as well as easily adjust the spreading angle divided by the dotted line from the short-point incident light L1 to several tens of degrees.

The optical scanning unit 120 is a unit for scanning the multi-point output light L2 of the dot line shape divided by the light splitting unit 110 in the form of a predetermined viewing angle. The multi-point output light L2 (Approximately 60 to 90 degrees) in a direction perpendicular to the scanning direction of the dotted line (FOV), so that scanning of the range of the viewing angle (FOV) To be done.

4, the optical scanning unit 120 may be disposed on the path of the multi-point output light L2 divided by the dot line passing through the diffraction optical filter 113, And a resonance type mirror 114 capable of scanning in a predetermined viewing angle form as it is driven at a predetermined angular velocity so as to reflect the dot-shaped multi-point output light L2 in a predetermined range of angles. However, It is needless to say that it is possible to have various configurations such as a general scanning mirror if the multi-point output light L2 of the light source can be reflected by a predetermined angle.

As described above, according to the configuration of the optical transmission module 100 including the light splitting unit 110 and the optical scanning unit 120, the optical axis of the short-point incident light L1 provided from the light source is aligned, It is possible to divide the light into light L2 and scan in a predetermined viewing angle.

Particularly, by using a multi-point output light L2 in the form of a dot line rather than a solid line for a three-dimensional scan, it is possible to increase the density of light received per unit scanning pixel, The weight of the optical transmission module 100 can be remarkably reduced, and the structure can be simplified.

Next, the light receiving module 200 and the controller 300 will be described.

The light receiving module 200 is a part for receiving the reflected light L3 reflected from the target after being emitted from the optical transmitter module 100 and receives the reflected light L3 to be transmitted to the controller 300 A lens 220 for receiving the reflected light L3, and a receiver 230. [

The reflected light L3 reflected from the target after being emitted from the optical transmission module 100 and received by the optical receiving module 200 is reflected by the resonant mirror 114 to be primarily switched, The path of the reflected light L2 is changed by the reflected light reflecting member 210 disposed on the path of the reflected light L3 reflected by the resonant mirror 114, The reflected light L3 may be received by the light receiving module 200. The reflected light L3 may be received by the receiver 230 through the recursive lens 225 and may be received on the inclined portion of the mirror holder 116, As shown in FIG.

The lens 220 is an aspherical lens and the cylindrical lens 225 is a lens having a lens surface formed in a circumferential side surface shape. For example, the lens 220 may be a lens 230 so that the reflected light L3 can be received at a specific position of the receiver 230. In addition,

On the other hand, a slit-shaped through hole 210h for passing the multi-point output light L2 in the form of a dot line divided by the diffraction optical filter 113 may be formed at the center of the reflected light reflecting member 210 have.

According to the configuration of the light receiving module 200 as described above, the reflected light L3 whose path is switched by the resonant mirror 114 and the reflected light reflecting member 210 is received, and the reflected light L3 To the controller 300. The controller 300 generates an image of the target based on the reflected light L3 received by the light receiving module 200. [

On the other hand, as shown in FIG. 9, the dot-shaped multi-point output light L2 divided by the diffraction optical filter 113 may have a smaller amount of light toward both ends, The lens 220 or the receiver 230 amplifying circuit can be applied to compensate for this. In Fig. 9, the vertical axis indicates the amount of light, and the horizontal axis indicates the length of the dot line.

As described above, according to the configuration of the three-dimensional laser scanning system including the optical transmitting module 100, the optical receiving module 200, and the controller 300, it is possible to provide the three-dimensional laser scanning system using the diffraction optical filter 113, Dimensional scanning is performed by dividing and emitting multi-point output light L2 in the form of a dot line rather than a solid line, so that a low-power light source is used, The number and the spreading angle of the multi-point output light L2 can be easily adjusted by changing the diffraction pattern of the diffraction optical filter 113, There is an advantage that it can be easily changed to fit.

Although the present invention has been described with reference to the preferred embodiments thereof with reference to the accompanying drawings, it will be apparent to those skilled in the art that many other obvious modifications can be made therein without departing from the scope of the invention. Accordingly, the scope of the present invention should be interpreted by the appended claims to cover many such variations.

100: optical transmission module 110:
111: collimator 112: incident light reflection member
113: diffractive optical filter 114: resonant mirror
115: light switching housing 115h:
116: mirror holder 120:
200: light receiving module 210:
210h: through hole 300: controller
L1: Negative point incident light L2: Multi point output light
L3: Reflected light

Claims (9)

An optical transmission module including a light splitting part for splitting the short point incident light into the multi point output light and an optical scanning part for scanning the multi point output light divided by the light splitting part in a predetermined viewing angle form;
A light receiving module for receiving the reflected light reflected from the target after being emitted from the optical transmitting module; And
And a controller for generating an image of a target based on the reflected light received by the light receiving module. The method according to claim 1,
The light-
And divides the short-point incident light into a multi-point output light in the form of a dot line extending at a predetermined angle. 3. The method of claim 2,
The optical scanning unit includes:
And the multi-point output light of the dot line shape is reflected at a predetermined angle angle in a direction perpendicular to the multi-point output light of the dot line form. The method of claim 3,
The optical scanning unit includes:
And a resonance type mirror. The method according to claim 1,
The light-
Wherein said diffraction optical filter is configured to divide the above-mentioned short-point incident light into multi-point output light through a diffraction optical filter in which a diffraction pattern is formed. The method according to claim 1,
The light-
A collimator for aligning the optical axis of the short point incident light provided from the light source;
An incident light reflecting member for changing the path of the short point incident light whose optical axis is aligned by the collimator; And
And a diffraction optical filter disposed on the path of the short point incident light reflected by the incident light reflecting member and dividing the short point incident light into the dot point type output light as passing the short point incident light,
The optical transmitter includes:
A diffraction optical filter for diffracting the multi-point output light of the dot line shape in a direction perpendicular to the dot-line-shaped multi-point output light, Type scanning system according to the present invention. The method according to claim 6,
The reflected light reflected from the target and received by the light receiving module after being emitted from the optical transmitting module,
A path is firstly reflected by the resonant mirror and the path is switched by the reflected light reflecting member disposed on the path of the reflected light reflected by the resonant mirror and is received by the light receiving module Dimensional scanning system. 8. The method of claim 7,
On the center side of the reflected light reflecting member,
And a through hole for passing the multi-point output light in the form of a dot line divided by the diffraction optical filter is formed. 8. The method of claim 7,
The light-
A light switching housing formed in a square shape and having a through hole formed therein;
And a mirror holder having one end provided at one end of the light switching housing and the other end formed with an inclined portion,
The collimator is provided at the other end of the light switching housing, and the incident light reflecting member is provided at a corner of the through hole formed in the light switching housing, and the reflected light reflecting member is disposed on the inclined portion of the mirror holder Dimensional scanning system.

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