CN209231507U - A kind of light path system and a kind of laser radar of laser radar - Google Patents

Abstract

The utility model provides a kind of light path system of laser radar and the laser radar with the light path system, the light path system includes: laser source, optical fiber, collimation lens, the first galvanometer, the second galvanometer, plus lens and reception device, the laser source issues laser, it is divided at least two laser beams via the optical fiber, it is emitted after the collimated collimated of laser beam to first galvanometer, and by the first vibration mirror reflected to the second galvanometer, then via the second vibration mirror reflected to target object.First galvanometer and the second galvanometer are moved with different frequencies towards different directions.Device is received after plus lens converges from the reflected laser beam of target object to receive.After adopting the above technical scheme, laser radar does not need mechanical rotational structure and multiple lasers, and there is bigger scan area and higher scanning density.

Description

A kind of light path system and a kind of laser radar of laser radar

Technical field

The utility model relates to the light path systems and one kind of laser radar technique field more particularly to a kind of laser radar to swash Optical radar.

Background technique

Laser radar technique is in the fields such as navigation, ground mapping, satellite positioning extensive application.It is unmanned in automobile In field, laser radar plays the key effect of ground mapping and scene positioning.

Existing laser radar is mostly mechanical laser radar.Mechanical laser radar generally requires mechanical rotating mechanism, Laser radar system is driven to carry out Space Rotating scanning by rotation.

The mechanical rotational structure requirement on machining accuracy of existing mechanical laser radar is higher, and rotational structure is easily using Middle abrasion, long-time stability are poor.In addition, mechanical laser radar in order to obtain higher resolution ratio, generally requires multi-thread measurement, Multiple lasers, higher cost are used simultaneously.

Due to mechanical laser radar be realize Surface scan by more laser rotaries side by side, so, the face of scanning Long-pending and density is smaller, it is difficult to meet the needs of market.Therefore, it is necessary to develop one kind do not need mechanical rotational structure and it is multiple swash Light device, and the light path system for the laser radar that scan area is big, scanning density is high and the laser radar with the light path system.

Summary of the invention

In order to overcome the above technical defects, the purpose of this utility model is to provide one kind do not need mechanical rotational structure and Multiple lasers, and the light path system for the laser radar that scan area is big, scanning density is high and the laser with the light path system Radar.

The utility model discloses a kind of light path system of laser radar, the light path system includes:

Laser source, for issuing laser；Optical fiber, the optical fiber connect the laser source, pass through for the laser, and by institute It states laser and is divided at least two laser beams；Collimation lens, the collimation lens are arranged in the exit direction of the laser beam, institute The quantity for stating collimation lens is identical as the laser beam quantity, collimates to the laser beam；First galvanometer is arranged through institute In the exit direction of laser beam after stating collimation lens collimation, first galvanometer is rotated around first axle periodic reverse, described First galvanometer reflects the laser beam；The outgoing of the laser beam through first vibration mirror reflected is arranged in second galvanometer On direction, second galvanometer is rotated around the second axial period reciprocating rotation or around the second axis along single direction, second axis Perpendicular to the first axle, the frequency of second galvanometer is different from first galvanometer, and second galvanometer is by the laser Beam is reflected towards target object；Plus lens is converged to from the reflected laser beam of the target object；Reception device, In the exit direction for the laser beam being arranged in after converging, the laser beam is received.

Preferably, first galvanometer is one-dimensional MEMS galvanometer.

Preferably, second galvanometer is moved back and forth around the second axial period, and the mirror surface number of second galvanometer is 1.

Preferably, second galvanometer is rotated around the second axis along single direction, and the mirror surface number of second galvanometer is 2~6.

Preferably, there are following relationships for the frequency of first galvanometer and the frequency of second galvanometer:

First galvanometer frequency=the second galvanometer frequency × number of scanning lines × second galvanometer mirror surface number ÷ 2；

The number of scanning lines is the scan line reciprocal back and forth that the single laser beam is formed on the target object Quantity.

Preferably, the frequency of first galvanometer is 5~30Hz.

Preferably, the number of scanning lines is 80~1080.

Preferably, the number of scanning lines is 300~600.

Preferably, the reception device is avalanche photodide.

The invention also discloses a kind of laser radar, the laser radar has above-mentioned light path system.

After above-mentioned technical proposal, compared with prior art, have the advantages that

1. the laser radar of the application changes the direction of the launch of laser by galvanometer, realizes the scanning to space, do not need Mechanical rotational structure.

2. the application laser radar increases the area of scanning by the laser beam splitter for issuing laser source.

3. the application laser radar two galvanometers different by frequency, increase the density of scanning.

Detailed description of the invention

Fig. 1 is to meet the laser of an embodiment of the present invention to issue from light source until target object, the optical path of the part System schematic；

Fig. 2 be meet an embodiment of the present invention laser be reflected into from target object be received device reception, the portion The light path system schematic diagram divided；

Fig. 3 is the structural schematic diagram of the second galvanometer mirror surface.

Fig. 4 is the scanning track schematic diagram that laser is formed in surface to be scanned；

Appended drawing reference:

1- laser source, 2- optical fiber, 3- collimation lens, the first galvanometer of 4-, the second galvanometer of 5-, 6- target object, 61- are scanned Face, 7- plus lens, 8- reception device, 9- scan line.

Specific embodiment

The advantages of the utility model is further described below in conjunction with attached drawing and specific embodiment.

It is a kind of light path system of laser radar referring to attached drawing 1, attached drawing 2, the light path system includes:

Laser source 1, for issuing laser.The laser source 1 can be solid state laser or semiconductor laser preferably Device or gas laser, the solid state laser can preferably be optical fiber laser.

Optical fiber 2, the optical fiber 2 connects the laser source 1, passes through for the laser, and the laser is divided into no less than 2 laser beams.Preferably, it is provided with laser beam splitter on the optical fiber 2, for the laser to be divided into multi beam.It is described to swash Beam splitter is preferably one-dimensional linear beam splitter.

Collimation lens 3, the collimation lens 3 are arranged in the exit direction of the laser beam, the collimation lens 3 Quantity is identical as the laser beam quantity, collimates to the laser beam.Since the laser that laser source 1 issues has larger hair Angle is dissipated, energy is not concentrated, and is unfavorable for the ranging of laser radar, so needing to collimate laser beam.The collimation lens 3 is excellent Selection of land can be spherical surface simple lens or combinatorial sphere lens or compound pier areal lens.It is each after the collimation lens 3 collimation Laser beam is not parallel to each other and converges towards the first galvanometer 4.

The exit direction of the laser beam after the collimation lens 3 collimation is arranged in-the first galvanometer 4, first galvanometer 4 On, first galvanometer 4 is rotated around first axle periodic reverse, and first galvanometer 4 reflects the laser beam.It is described First galvanometer 4, it is preferable that be one-dimensional MEMS galvanometer (MEMS galvanometer, Micro Electro Mechanical System galvanometer), i.e., the described MEMS galvanometer can change the direction of optical path in one direction.The MEMS The driving method of galvanometer, it is preferable that can be by the way of electromagnetic drive.Usually there are two types of forms for electromagnetic drive, and one is electricity Surface is placed on the MEMS galvanometer of the good metals of magnetic properties such as iron-cobalt-nickel and becomes according to certain frequency by magnet type In the alternating magnetic field of change, magnetic drive galvanometer is generated using alternating magnetic field and metal interaction and is reversed around a central axis；It is another Kind is bipolar subtype, needs to deposit magnetic material, the work generated under alternating electric field using magnetic material on MEMS galvanometer Firmly, driving galvanometer is reversed around a central axis.When the alternating magnetic field and alternating electric field have periodic frequency, can be driven Galvanometer is rotated around a central axis periodic reverse, and then drives the laser beam generating period deflection being incident on mirror surface.It is preferred that The driving method on ground, the MEMS galvanometer can also be by the way of electrostatic drive, Piezoelectric Driving or electrothermal drive.

The exit direction of the laser beam through first galvanometer 4 reflection is arranged in-the second galvanometer 5, second galvanometer 5 On, second galvanometer 5 is rotated around the second axial period reciprocating rotation, or around the second axis along single direction, and second axis hangs down Directly in the first axle.By being vertically arranged for the first axle and second axis, can make through first galvanometer 4 and The laser beam of two galvanometers 5 reflection moves in two mutually perpendicular directions, to realize two-dimensional scanning.

As shown in figure 3, in some embodiments, the second galvanometer 5 is around the second axial period reciprocating rotation, the second galvanometer at this time 5 mirror surface number is 1 (as shown in first figure in Fig. 3), i.e. only one reflecting surface, at this point, the second galvanometer 5 can be one-dimensional MEMS galvanometer.In further embodiments, the second galvanometer 5 is rotated around the second axis along single direction, at this time the second galvanometer 5 Mirror surface number (the case where second to the 5th graphical display mirror surface number is 3~6 in Fig. 3 that be 2~6；The case where mirror surface number is 2 It is similar with first figure in figure, the difference is that there is 2 reflectings surface), that is, there is 2~6 reflectings surface, second axle position The center of mirror surface figure in figure, in the direction perpendicular to paper.Single direction mentioned here refers to along clockwise or inverse The direction of hour hands.

The frequency of second galvanometer 5 is different from first galvanometer 4, and frequency difference mentioned here refers to the second galvanometer The frequency of the frequency of 5 periodic reverses rotation or frequency and the rotation of the first galvanometer periodic reverse along single direction rotation is not Together.Since the rotor shaft direction of the first galvanometer 4 and the second galvanometer 5 is vertical, if the frequency phase of the two galvanometer periodic reverses rotation Together, then laser beam can be to move with scanned edges of regions in the direction of 45° angle, and scanning density is fixed.Therefore, by making first Galvanometer 4 and the second galvanometer 5 are with different frequency periodicity reciprocating rotations, specifically, quick rotation in one direction, a direction Slow rotation, so that it may realize the intensive scanning to scanned region.It is laser beam being swept in target object 6 referring to attached drawing 4 Retouch the scanning track schematic diagram formed on face 61.It can be seen from the figure that vertical direction quick of the single laser beam in surface to be scanned Speed is mobile, moves slowly in the horizontal direction, thus realize the intensive scanning of two-dimensional directional, and mostly with the presence of laser beam, so that Scan area is multiplied.Preferably, there are following relationships for the frequency of first galvanometer 4 and the frequency of second galvanometer 5:

First galvanometer frequency=the second galvanometer frequency × number of scanning lines × second galvanometer mirror surface number ÷ 2

The number of scanning lines forms in the surface to be scanned of the target object reciprocal back and forth for the single laser beam Scan line 9 quantity.

The frequency of second galvanometer is determined according to the refresh rate of laser radar, usually takes 5~30Hz.The scan line Usually in the range of 80~1080, the scanning effect to be realized according to laser radar determines specific value for number.Preferably, Number of scanning lines usually takes 300~600.

Following table is that preferred number of scanning lines, the mirror surface number of the second galvanometer, the second galvanometer frequency, the first galvanometer frequency take Value.

Plus lens 7 is focused it onto and is connect for converging to from the reflected laser beam of the target object 6 On receiving apparatus 8, by the convergence of plus lens 7, reflected laser beam is made to concentrate on lesser region, is filled to make to receive It sets 8 it goes without doing also be able to achieve very much preferable reception greatly.Reduce the volume and reception device of laser radar apparatus entirety Cost.

Reception device 8 in the exit direction for the laser beam being arranged in after converging, receives the laser beam.Preferably, The reception device 8 is multiple avalanche photodides (APD).In some embodiments, 8 position of reception device is fixed. In further embodiments, the reception device 8 is rotated synchronously with second galvanometer, to realize better reception.

The specific course of work of the light path system of the application laser radar are as follows: laser source 1 issues laser, the laser warp of sending At least two laser beams are divided by the optical fiber 2, every laser beam is emitted after being set the collimation of collimation lens 3 behind to institute The first galvanometer 4 is stated, and the second galvanometer 5 is reflected towards by the first galvanometer 4, is then reflected towards target object 6 via the second galvanometer 5.The One galvanometer 4 is rotated around first axle periodic reverse, and the second galvanometer 5 is around the second axial period reciprocating rotary or around the second axis along single Direction rotates, and first axle and the second axis are orthogonal.Meanwhile first galvanometer 4 and the second galvanometer 5 rotated with different frequencies.By The frequency of and periodic reverse vertical from the shaft of the second galvanometer 5 in the first galvanometer 4 rotation is different, so that single laser beam can be with More highdensity scanning is realized in two-dimensional directional.And more laser beams can form multiple scanning areas, so that total scanning surface Product increases.Device 8 is received after the convergence of plus lens 7 from the reflected laser beam of target object 6 to receive.Further, The case where central control system on laser radar sends and receives according to laser, in conjunction with the first galvanometer 4 and the second galvanometer 5 frequency and Angle information, can with the position (distance and angle) of precise measurement target object 6, motion state (speed, vibration and posture) and Target is differentiated and is tracked in shape, detection, identification.

In some embodiments, after the collimated lens 3 of laser beam collimate, the second galvanometer 5 is first passed through, using the first galvanometer 4, it is then emitted to target object 6.

The invention also discloses a kind of laser radar, the laser radar has above-mentioned light path system.

It should be noted that the embodiments of the present invention have preferable implementation, and not the utility model is appointed The limitation of what form, any one skilled in the art change or are modified to possibly also with the technology contents of the disclosure above Same effective embodiment, as long as without departing from the content of technical solutions of the utility model, according to the technical essence of the utility model pair Any modification or equivalent variations and modification, are still within the scope of the technical solutions of the present invention made by above embodiments.

Claims (10)

1. a kind of light path system of laser radar, which is characterized in that

The light path system includes:

Laser source, for issuing laser；

Optical fiber, the optical fiber connect the laser source, pass through for the laser, and the laser is divided at least two laser Beam；

Collimation lens, the collimation lens are arranged in the exit direction of the laser beam, the quantity of the collimation lens and institute It is identical to state laser beam quantity, the laser beam is collimated；

First galvanometer is arranged in the exit direction of the laser beam after collimation lens collimation, and first galvanometer is around the One axial period moves back and forth, and first galvanometer reflects the laser beam；

Second galvanometer is arranged in the exit direction of the laser beam through first vibration mirror reflected, and second galvanometer is around second Axial period reciprocating rotation is rotated around the second axis along single direction, and second axis is perpendicular to the first axle, and described second The frequency of galvanometer is different from first galvanometer, and the laser beam is reflected towards target object by second galvanometer；

Plus lens is converged to from the reflected laser beam of the target object；

Reception device in the exit direction for the laser beam being arranged in after converging, receives the laser beam.

2. light path system as described in claim 1, which is characterized in that first galvanometer is one-dimensional MEMS galvanometer.

3. light path system as described in claim 1, which is characterized in that second galvanometer is around the second axial period reciprocating rotary Dynamic, the mirror surface number of second galvanometer is 1.

4. light path system as described in claim 1, which is characterized in that second galvanometer turns around the second axis along single direction Dynamic, the mirror surface number of second galvanometer is 2~6.

5. light path system as described in claim 3 or 4, which is characterized in that the frequency of first galvanometer and second vibration There are following relationships for the frequency of mirror:

First galvanometer frequency=the second galvanometer frequency × number of scanning lines × second galvanometer mirror surface number ÷ 2；

The number of scanning lines is the quantity for the scan line reciprocal back and forth that the single laser beam is formed on the target object.

6. light path system as claimed in claim 5, which is characterized in that the frequency of first galvanometer is 5~30Hz.

7. light path system as claimed in claim 6, which is characterized in that the number of scanning lines is 80~1080.

8. light path system as claimed in claim 7, which is characterized in that the number of scanning lines is 300~600.

9. light path system as described in claim 1, which is characterized in that the reception device is avalanche photodide.

10. a kind of laser radar, which is characterized in that the laser radar has light path system as claimed in claims 1-9.