CN103926574B - Laser radar optical receiver assembly - Google Patents
Laser radar optical receiver assembly Download PDFInfo
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- CN103926574B CN103926574B CN201410177032.9A CN201410177032A CN103926574B CN 103926574 B CN103926574 B CN 103926574B CN 201410177032 A CN201410177032 A CN 201410177032A CN 103926574 B CN103926574 B CN 103926574B
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- wave plate
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- laser radar
- optical receiver
- receiver assembly
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
- G01S7/48—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S17/00
- G01S7/481—Constructional features, e.g. arrangements of optical elements
- G01S7/4816—Constructional features, e.g. arrangements of optical elements of receivers alone
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- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Optical Radar Systems And Details Thereof (AREA)
Abstract
A kind of laser radar optical receiver assembly, is made up of telescope, field stop, collimating lens, 1/2 wave plate, rotary electric machine, electro-optic crystal, polariser, narrow band pass filter, condenser lens, photodetector, high voltage power supply and motor servo control system.Described field stop is positioned at telescopical focal position, through the echo-signal of field stop after collimating lens collimates, intensity modulation is carried out by 1/2 wave plate, electro-optic crystal and polariser, by narrow band pass filter, bias light being carried out bandpass filter, flashlight is focused on and detects on photodetector by last line focus lens.The present invention has simple in construction, the easy to use and continuously adjustable advantage of splitting ratio, can be applicable to the laser radar system found range on a large scale.
Description
Technical field
The present invention relates to laser radar, particularly a kind of laser radar optical receiver assembly.
Background technology
Laser radar has a wide range of applications in terms of earth remote sensing, in order to reduce atmospheric scattering to mesh
Mark echo-signal interference, improve signal to noise ratio, traditional method typically use channel structure design and
The method of timesharing gating is found range, and to prevent photodetector to be operated in saturation region, it receives light
Road, as it is shown on figure 3, the optical signal that telescope 1 receives focuses near focal point, is put in focal position
Put field stop 2 and limit field of view of receiver, after optical signal collimated lens 3 collimation, incide arrowband filter
Mating plate 8, then by spectroscope 13, receiving light path is divided near field and two, far field passage, wherein: near
Field passage line focus lens 9.1 focus on photodetector 10.1 and detect；Far field passage is through folding
Anti-mirror 14 and condenser lens 9.2 focus on photodetector 10.2 and detect.Obviously, above-mentioned connect
Receiving light path and need two-way photodetection, not only volume is relatively big, cost increases, and, splitting ratio is solid
Fixed, it is impossible to continuously adjustabe, therefore limit its application.
Summary of the invention
It is an object of the invention to provide a kind of laser radar optical receiver assembly, this device has light
Road is simple, the feature of good stability, can be applicable to laser radar and other needs to remove bias light
Optical system.
The technical scheme is that
A kind of laser radar optical receiver assembly, including telescope, field stop, collimating lens,
1/2 wave plate, rotary electric machine, electro-optic crystal, polariser, narrow band pass filter, condenser lens, photoelectricity
Detector, high voltage power supply and motor servo control system, it is characterised in that defeated along described telescope
Light direction be successively field stop, collimating lens, 1/2 wave plate, rotary electric machine, electro-optic crystal,
Polariser, narrow band pass filter, condenser lens and photodetector, the two poles of the earth of high voltage power supply are with described
Electro-optic crystal two ends be connected, motor servo control system is connected with described rotary electric machine, institute
The field stop stated is positioned at telescopical focal position, by 1/2 described ripple by the way of gluing
Sheet is adhesive on described open-core type rotary electric machine, the geometric center of 1/2 described wave plate and rotation
Electrical axis overlaps.
Described telescope objective is coated with, with eyepiece surface, the high reflectance being consistent with laser source wavelength
Deielectric-coating, and its F number is more than 5.
The surface of described collimating lens is coated with anti-reflection deielectric-coating corresponding with laser source wavelength.
1/2 described wave plate surface is coated with the anti-reflection deielectric-coating being consistent with laser source wavelength.
Described electro-optic crystal surface is coated with the anti-reflection deielectric-coating being consistent with laser source wavelength.
Described narrow band pass filter surface is coated with the anti-reflection deielectric-coating being consistent with laser source wavelength, and
Its incident angle θ meets following relation:
Wherein: θ is the incident angle of light beam；λθWhen being θ for beam incident angle, in narrow band pass filter
Cardiac wave is long；λ0When being 0 ° for beam incident angle, the centre wavelength of narrow band pass filter；Ne is air
Refractive index, typically takes 1；N*Refractive index for narrow band pass filter.
The surface of described condenser lens is coated with the anti-reflection deielectric-coating being consistent with laser source wavelength.
The implementation method of this device comprises the following steps:
1. respectively rotatable polarizer and 1/2 wave plate, make polariser is polarized direction and 1/2 wave plate
Fast axle or slow axis are vertical with the polarization direction of line polarisation, and are set as at the beginning of 1/2 wave plate this position
Beginning position, the echo light intensity that telescope receives is I0；
2. near field range finding, when 1/2 wave plate is along initial position anglec of rotation α, emergent light polarization side
To be polarized angular separation for (90 ° of-2 α), electro-optic crystal is not added with voltage, through the line of electro-optic crystal
Polarisation polarization state does not changes, and now the light intensity through polariser outgoing is I1=I0·cos
(90°-2α)；Polarized light carries out bandpass filter by narrow band pass filter to bias light, eventually passes poly-
Flashlight is focused on and detects on photodetector by focus lens；
3. far field range finding, owing to 1/2 wave plate is along initial position rotation alpha angle, so, through 1/2
After wave plate, emergent light polarization direction be polarized angular separation still for (90 ° of-2 α), electro-optic crystal adds
Vλ/2Voltage, light produces π phase contrast, synthesis along optical axis direction by electro-optic crystal, o light and e light
Rear polarizer face is relative to incident illumination half-twist, and now the light intensity through polariser outgoing is I2=I0·cos
(2 α), the polarized light after modulation carries out bandpass filter by narrow band pass filter to bias light, after warp
Flashlight is focused on and detects on photodetector by over-focusing lens；
4. the splitting ratio γ of laser radar optical receiver assembly and 1/2 wave plate are along the initial position anglec of rotation
Relation between degree α is:
Controlling rotary electric machine by motor servo control system drives 1/2 wave plate to rotate, thus realizes
Laser radar optical receiver assembly near field and the on-line tuning of far field splitting ratio γ.
The technique effect of the present invention:
The present invention can realize the twin-channel mode near field and far field and receive laser radar echo optical signal,
Compared with traditional method, advantage is: simple in construction, splitting ratio continuously adjustabe, good stability,
And can be by rotating 1/2 wave plate, it is achieved the dynamic realtime regulation of splitting ratio, can be applicable to laser thunder
Reach in the optical system that reception system needs to remove bias light with other.
Accompanying drawing explanation
Fig. 1 is laser radar optical receiver assembly light channel structure schematic diagram of the present invention.
Fig. 2 is light intensity modulation principle schematic diagram of the present invention.
Fig. 3 is general laser radar optical receiver assembly light channel structure schematic diagram.
Detailed description of the invention
Referring to Fig. 1, Fig. 1 is laser radar optical receiver assembly light channel structure schematic diagram of the present invention.
As seen from the figure, a kind of laser radar optical receiver assembly, including telescope 1, field stop 2, standard
Straight lens 3,1/2 wave plate 4, rotary electric machine 5, electro-optic crystal 6, polariser 7, narrow band pass filter
8, condenser lens 9, photodetector 10, high voltage power supply 11 and motor servo control system 12,
It is characterized in that along described telescope 1 export light direction be successively field stop 2, collimating lens 3,
1/2 wave plate 4, rotary electric machine 5, electro-optic crystal 6, polariser 7, narrow band pass filter 8, focusing are thoroughly
The two ends of mirror 9 and photodetector 10, the two poles of the earth of high voltage power supply 11 and described electro-optic crystal 6
Being connected, motor servo control system 12 is connected with described rotary electric machine 5, described field stop
2 focal positions being positioned at telescope 1, are adhesive in 1/2 described wave plate 4 by the way of gluing
On described open-core type rotary electric machine 5, the geometric center of 1/2 described wave plate 4 and rotary electric machine 5
Dead in line.
Described telescope 1 object lens are coated with the high reflection being consistent with laser source wavelength with eyepiece surface
Rate deielectric-coating, and its F number is more than 5.
The surface of described collimating lens 3 is coated with anti-reflection deielectric-coating corresponding with laser source wavelength.
1/2 described wave plate 4 surface is coated with the anti-reflection deielectric-coating being consistent with laser source wavelength.
Described electro-optic crystal 6 surface is coated with the anti-reflection deielectric-coating being consistent with laser source wavelength.
The surface of described condenser lens 9 is coated with the anti-reflection deielectric-coating being consistent with laser source wavelength.
The implementation method of this device comprises the following steps:
1. distinguishing rotatable polarizer 7 and 1/2 wave plate 4, make polariser 7 is polarized direction and 1/2 ripple
The fast axle of sheet 4 or slow axis are vertical with the polarization direction of line polarisation, and this position is set as 1/2 ripple
The initial position of sheet, the echo light intensity that telescope 1 receives is I0；
2. near field range finding, when 1/2 wave plate 4 is along initial position anglec of rotation α, emergent light polarizes
Direction is (90 ° of-2 α) with being polarized angular separation, electro-optic crystal 5 is not added with voltage, through electro-optic crystal
The line polarisation polarization state of 5 does not changes, and now the light intensity through polariser 7 outgoing is I1=I0·cos
(90°-2α)；Polarized light carries out bandpass filter by narrow band pass filter 8 to bias light, eventually passes
Flashlight is focused on photodetector 10 and detects by condenser lens 9；
3. far field range finding, owing to 1/2 wave plate 4 is along initial position rotation alpha angle, so, through 1/2
After wave plate 4, emergent light polarization direction is still (90 ° of-2 α) with being polarized angular separation, electro-optic crystal 5
On add Vλ/2Voltage, light produces π phase contrast along optical axis direction by electro-optic crystal 5, o light and e light,
Synthesis rear polarizer face is relative to incident illumination half-twist, and now the light intensity through polariser 7 outgoing is
I2=I0Cos (2 α), the polarized light after modulation carries logical filter by narrow band pass filter 8 to bias light
Light, eventually passes condenser lens 9 and is focused on by flashlight on photodetector 10 and detect；
4. splitting ratio γ and 1/2 wave plate 4 of laser radar optical receiver assembly rotates along initial position
Relation between angle [alpha] is:
Controlling rotary electric machine 5 by motor servo control system 12 drives 1/2 wave plate 4 to rotate, from
And realize laser radar optical receiver assembly near field and the on-line tuning of far field splitting ratio γ.
When the angle of rotation precision of the rotary electric machine selected is δα=0.00008rad, optical maser wavelength
λ=1064nm, telescope 1F number is 8.5, and RTP selected by electro-optic crystal 6, two pieces of RTP crystalline substances
Body is orthogonally located, parallel operation, reduces half-wave voltage V furtherλ/2, air selected by polariser 7
Gap Glan-Fu Ke prism, photodetector 10 selects the model of Excelitas company to be
C30659-1060-R8BH APD detector, this detector is integrated with frontend amplifying circuit.If swashing
The echo light intensity that optical radar receives is I0, then under near field mode, through the light intensity of polariser 7 outgoing
For I1, under Far Field Pattern, it is I through the light intensity of polariser 7 outgoing2, then near field and the maximum in far field
Splitting ratio γ is represented by:
Narrow band pass filter 8 incident angle θ and its central wavelength lambda0There is following functional relationship:
Bandwidth Delta lambda=the 1nm of the narrow band pass filter 8 selected, refractive index is N*=1.44963,
Therefore, the incidence angle θ of narrow band pass filter 8 should meet following relation:
Wherein: λθWhen being θ for beam incident angle, the centre wavelength of narrow band pass filter 8；λ0Enter for light beam
When firing angle is 0 °, the centre wavelength of narrow band pass filter 8；NeFor air refraction, typically take 1；
N*Refractive index for narrow band pass filter 8；θ is the incident angle of light beam.
From formula (1), the splitting ratio γ of laser radar optical receiver assembly exists with angle α
Functional relationship, by regulation α value, can realize the continuously adjustabe of splitting ratio γ, and maximum light splitting
Than γ it is: γ=1.6 × 10-4: 1.From formula (3) and formula (4), for bandwidth Delta lambda=1nm
Narrow band pass filter 8, its incident angle θ should meet θ≤2.55 °.
In conventional methods where, the general method using channel structure design and timesharing gating is surveyed
Away from, splitting ratio is ensured by plated film, and splitting ratio is fixed, and unadjustable, structural volume is bigger.
Therefore, method involved in the present invention is not only simple in structure, convenient use, and light splitting precision
It is improved significantly.
In sum, compared with traditional method, laser radar optics mentioned in the present invention receives
Apparatus structure is simple, splitting ratio continuously adjustabe, good stability, and light splitting precision significantly improves, it is possible to
Need the optical system of removal bias light obtains extensively should with other in laser radar reception system
With.
Claims (8)
1. a laser radar optical receiver assembly, including telescope (1), field stop (2),
Collimating lens (3), 1/2 wave plate (4), rotary electric machine (5), electro-optic crystal (6), polariser (7),
Narrow band pass filter (8), condenser lens (9), photodetector (10), high voltage power supply (11) and
Motor servo control system (12), it is characterised in that along described telescope (1) output light direction
It is field stop (2), collimating lens (3), 1/2 wave plate (4), rotary electric machine (5), electricity successively
Luminescent crystal (6), polariser (7), narrow band pass filter (8), condenser lens (9) and photodetection
Device (10), the two poles of the earth of high voltage power supply (11) are connected with the two ends of described electro-optic crystal (6),
Motor servo control system (12) is connected with described rotary electric machine (5), described field stop
(2) focal position of telescope (1) it is positioned at, by 1/2 described wave plate by the way of gluing
(4) it is adhesive on described rotary electric machine (5), the geometric center of described 1/2 wave plate (4)
With rotary electric machine (5) dead in line.
Laser radar optical receiver assembly the most according to claim 1, it is characterised in that described
Telescope (1) object lens be coated with the high reflectance medium being consistent with laser source wavelength with eyepiece surface
Film, and its F number is more than 5.
Laser radar optical receiver assembly the most according to claim 1, it is characterised in that described
The surface of collimating lens (3) be coated with anti-reflection deielectric-coating corresponding with laser source wavelength.
Laser radar optical receiver assembly the most according to claim 1, it is characterised in that described
1/2 wave plate (4) surface be coated with the anti-reflection deielectric-coating being consistent with laser source wavelength.
Laser radar optical receiver assembly the most according to claim 1, it is characterised in that described
Electro-optic crystal (6) surface be coated with the anti-reflection deielectric-coating being consistent with laser source wavelength.
Laser radar optical receiver assembly the most according to claim 1, it is characterised in that described
Narrow band pass filter (8) surface be coated with the anti-reflection deielectric-coating being consistent with laser source wavelength, and it enters
Penetrate angle, θ and meet following relation:
Wherein: θ is the incident angle of light beam；λθWhen being θ for beam incident angle, narrow band pass filter (8)
Centre wavelength；λ0When being 0 ° for beam incident angle, the centre wavelength of narrow band pass filter (8)；
Ne is air refraction, typically takes 1；N*Refractive index for narrow band pass filter (8).
Laser radar optical receiver assembly the most according to claim 1, it is characterised in that described
The surface of condenser lens (9) be coated with the anti-reflection deielectric-coating being consistent with laser source wavelength.
Laser radar optical receiver assembly the most according to claim 1, it is characterised in that this dress
The implementation method put comprises the following steps:
1. distinguishing rotatable polarizer (7) and 1/2 wave plate (4), make polariser (7) plays folk prescription
To vertical with the polarization direction of line polarisation with the fast axle of 1/2 wave plate (4) or slow axis, and by this position
It is set as that the initial position of 1/2 wave plate, the echo light intensity that telescope (1) receives are I0；
2. near field range finding, when 1/2 wave plate (4) is along initial position anglec of rotation α, emergent light is inclined
Shaking direction and being polarized angular separation is (90 ° of-2 α), electro-optic crystal (5) is not added with voltage, through electricity
The line polarisation polarization state of luminescent crystal (5) does not changes, now through polariser (7) outgoing
Light intensity is I1=I0·cos(90°-2α)；Bias light is carried out by polarized light by narrow band pass filter (8)
Bandpass filter, eventually passes condenser lens (9) and is focused on by flashlight on photodetector (10)
Detect；
3. far field range finding, owing to 1/2 wave plate (4) is along initial position rotation alpha angle, so, warp
After 1/2 wave plate (4), emergent light polarization direction is still (90 ° of-2 α) with being polarized angular separation, electric light
Crystal adds V on (5)λ/2Voltage, light passes through electro-optic crystal (5), o light and e light along optical axis direction
Producing π phase contrast, synthesis rear polarizer face is relative to incident illumination half-twist, now through polariser (7)
The light intensity of outgoing is I2=I0Cos (2 α), the polarized light after modulation is right by narrow band pass filter (8)
Bias light carries out bandpass filter, eventually passes condenser lens (9) and flashlight is focused on photodetection
Device detects on (10)；
4. splitting ratio γ and 1/2 wave plate (4) of laser radar optical receiver assembly revolves along initial position
Relation between gyration α is:
Control rotary electric machine (5) by motor servo control system (12) and drive 1/2 wave plate (4)
Rotate, thus realize laser radar optical receiver assembly near field and the on-line tuning of far field splitting ratio γ.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201410177032.9A CN103926574B (en) | 2014-04-29 | 2014-04-29 | Laser radar optical receiver assembly |
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| CN201410177032.9A CN103926574B (en) | 2014-04-29 | 2014-04-29 | Laser radar optical receiver assembly |
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| CN103926574B true CN103926574B (en) | 2016-08-31 |
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Families Citing this family (18)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN104834079B (en) * | 2015-04-24 | 2017-04-05 | 中国科学院西安光学精密机械研究所 | Long-focus large-caliber large-F-number telescopic imaging system |
| CN104898108A (en) * | 2015-05-19 | 2015-09-09 | 浙江大学 | Atmosphere remote sensing laser radar optical receiving device based on telescope arrays |
| CN105785389A (en) * | 2016-03-04 | 2016-07-20 | 中国科学院光电技术研究所 | Three-dimensional imaging laser radar system |
| CN105785341A (en) * | 2016-05-03 | 2016-07-20 | 中国科学院上海技术物理研究所 | Novel dual-channel laser radar receiving system for enhancing echo dynamic range |
| CN106154248A (en) * | 2016-09-13 | 2016-11-23 | 深圳市佶达德科技有限公司 | A kind of laser radar optical receiver assembly and laser radar range method |
| CN108169755A (en) * | 2017-12-14 | 2018-06-15 | 中国航空工业集团公司洛阳电光设备研究所 | A kind of High Precision Long-distance laser range finder and distance measuring method |
| CN108181628A (en) * | 2018-01-23 | 2018-06-19 | 上海兰宝传感科技股份有限公司 | A kind of anti-interference distance measuring sensor based on TOF |
| DE102018221083A1 (en) * | 2018-12-06 | 2020-06-10 | Robert Bosch Gmbh | LiDAR system and motor vehicle |
| CN115267742A (en) * | 2018-12-27 | 2022-11-01 | 深圳市速腾聚创科技有限公司 | Laser radar receiving system |
| CN110109084B (en) * | 2019-06-03 | 2021-08-17 | 北京未感科技有限公司 | Laser receiving device, noise reduction method and laser radar |
| CN110275154B (en) * | 2019-07-05 | 2021-11-02 | 哈尔滨工业大学 | Laser radar polarization detection optical adjusting mechanism |
| WO2021051723A1 (en) * | 2020-01-03 | 2021-03-25 | 深圳市速腾聚创科技有限公司 | Laser transceiving module and lidar |
| CN111708037B (en) * | 2020-06-24 | 2023-08-25 | 清华大学 | Passive measuring head and double-optical comb measuring system based on tunable bandpass filter |
| CN112394341A (en) * | 2020-11-26 | 2021-02-23 | 上海工程技术大学 | Vehicle-mounted laser radar range measurement testing system and method |
| DE102021105888A1 (en) * | 2021-03-11 | 2022-09-15 | Scoobe3D Gmbh | Optical system for obtaining 3D spatial information |
| CN113206708B (en) * | 2021-05-06 | 2022-06-14 | 西安邮电大学 | High-dynamic underwater wireless light receiving system |
| CN115437159A (en) * | 2021-06-02 | 2022-12-06 | 华为技术有限公司 | Optical system, lighting system and display system |
| CN114624682B (en) * | 2022-05-17 | 2022-09-30 | 中国科学技术大学 | Method and system for suppressing near field strength echo signal |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN100561254C (en) * | 2006-04-17 | 2009-11-18 | 武汉大学 | The atmospheric exploration laser radar of based semiconductor laser instrument |
| US8922873B2 (en) * | 2011-02-11 | 2014-12-30 | University Of Dayton | Compact narrow bandwidth tunable source |
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