CN209928021U - Dual-wavelength multi-polarization laser imaging device - Google Patents
Dual-wavelength multi-polarization laser imaging device Download PDFInfo
- Publication number
- CN209928021U CN209928021U CN201920414456.0U CN201920414456U CN209928021U CN 209928021 U CN209928021 U CN 209928021U CN 201920414456 U CN201920414456 U CN 201920414456U CN 209928021 U CN209928021 U CN 209928021U
- Authority
- CN
- China
- Prior art keywords
- polarization
- photon
- beam splitter
- polarized
- photons
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Landscapes
- Length Measuring Devices By Optical Means (AREA)
Abstract
The patent discloses a dual wavelength multi-polarization laser image device, output are 532nm and 1064nm wavelength level, two perpendicular polarization directions 100 wave beam linear array laser light sources based on DOE beam split, scan from top to bottom through the two-dimensional revolving stage can obtain the single polarization state's of 4 single wavelength target object photon count imaging graph. The surface characteristics of the target can be analyzed by comparing the images, and whether the surface of the target is a metal material or not is identified. The advantage of high photon counting detection sensitivity is combined with the polarization detection of the target, so that the detection efficiency of the whole system is improved, and the identification of the surface information of the target is realized. The single photon magnitude detection technology with multiple wavelengths and multiple polarization states combines the multiple polarization states with the few photon detection technology, so that the single photon detector can not only count the intensity information of the target echo, but also further enrich the application range of the single photon detection system by obtaining the surface polarization information of the target, and provide a new idea for the development of laser radars in the future.
Description
The technical field is as follows:
the patent relates to the field of active photoelectric technology, in particular to a multi-beam laser radar imaging system.
Background art:
laser radar (LiDAR) belongs to the laser detection and measurement range, is different from the traditional microwave radar, and detects a target by utilizing the characteristics of small laser emission power, high angular resolution, high processing speed and the like. In recent years, performance of the laser radar is greatly improved, and besides basic information such as simple distance and speed, the laser radar is developed into the existing multi-beam imaging laser radar, and can accurately provide various characteristic parameters such as size and shape of a target object and even establish a three-dimensional model in real time.
In the field of deep space exploration, lidar is endowed with new tasks and requirements. Firstly, the requirement on detection distance is more and more increased, and not only is the accurate positioning of a target object at dozens of kilometers under the atmospheric environment required, but also the detection and identification of micro satellites or space debris at thousands of kilometers in the space detection field are required; correspondingly, due to the increase of the detection distance, the received echo signal is very weak, and a detector with high resolution and high sensitivity needs to be further researched; in addition, the identification of the material of the detection target and the differentiation of different target objects are also widely regarded. Therefore, it is of great significance to carry out photon polarization characteristic research on the echo signal of the detection target.
At present, most schemes adopting an active laser light source as polarization detection adopt polarization reception at a receiving end of a detector, systematic research is not carried out on a transmitting end of a laser, and unstable elliptical polarized light transmitted by most lasers also influences polarization statistics of photon counting at the receiving end.
The invention content is as follows:
in order to overcome the deficiencies of the prior art, the present patent provides a dual wavelength multi-polarization laser imaging device. The concept is re-conceived from the light source transmitting end, so that the whole system can transmit four linear polarization laser light sources with two polarization states of two wavelengths of a 100-beam linear array in a time-sharing manner, and the receiving end can distinguish the four linear polarization light sources and count photon information. The advantage of high photon counting detection sensitivity is combined with the characteristic of identifying the polarization detection of the target object, so that a three-dimensional image of the target object containing high-precision distance information can be obtained, and the reflection characteristic of the surface of the target object can be obtained, thereby achieving the aim of identifying different target objects.
When a photon propagates in a cross section of a medium, the polarization change of the photon follows the law of refraction and the law of fresnel reflection, as shown in equation 1. For non-metallic media, the electric field of the photons of S and P light may change direction and intensity after refraction or reflection, but the polarization direction of the photons is not changed.
Wherein E0s、E0pRepresenting the amplitude, E ', of incident S-polarized light and P-polarized light'0s、E'0pRepresents the amplitude of light reflected by S-polarized light and P-polarized light, and E'0's、E'0'pRespectively representing the light amplitude, n, of S-polarized light and P-polarized light after refraction1、n2Respectively, refractive indices of medium 1 and medium 2, and theta, theta', theta "respectively represent an incident angle, a reflection angle, and a refraction angle of light.
When the light wave propagates in the metal interface, the distribution of the light field propagating in the metal interface satisfies the Helmholtz equation:
wherein
In this case, the refractive index is also complex,
where n is the real part of the refractive index and κ is the decay exponent.
Setting the photon secondary refractive index to n1Is incident on a complex refractive index at an angle theta ofThe metal surface of (2). The fresnel formula is shown in equation 3:
whereinIs a birefringence angle, rsIs the reflection coefficient of S wave, rpIs the reflection coefficient of the P-wave.
Setting up
Law of refraction
And formula (3) can be solved for u2、v2The value of (c). The compound obtained by substituting (5) for the formula (4):
thereby obtaining the reflectivity of the S-polarized optical electric field vibration:
the variation of the phase angle of the S-polarized light field:
reflectance of P-polarized light electric field vibration:
variation of phase angle of P-polarized light field:
therefore, for a flat metal surface, the polarization directions of the S wave and the P wave are kept unchanged, and the detection of the polarization state is not influenced only by the change of the amplitude and the phase.
The linear polarizations of the other polarization directions can be represented by jones matrices:
the reflected light reflected by the metal interface may be represented as:
wherein δ is δp-δs
When the light is reflected by a flat metal surface, for linear polarization light which is not S-polarized light and P-polarized light, the factors influencing the polarization state of the system are mainly the reflectivity and phase difference of the S-polarized light and the P-polarized light, so that the linear polarization light is changed into elliptical polarization light after being reflected.
In summary, the reflection of the metal surface acts on linearly polarized light generally as a two-way attenuation and phase retardation, and the rough nature of the metal surface causes the polarized laser light to be diffusely reflected and depolarized. The component reflectance of the metal surface S, P is generally much greater than the surface reflectance of non-metallic substances, and the higher the magnetic metal content of different metals, the more pronounced the change. By combining the advantage of high single photon detection sensitivity, the number of received echo photons of linearly polarized light in two polarization directions can be counted, so that whether the surface of a target object is metal or nonmetal or not can be distinguished, and even different metal surfaces can be distinguished.
The technical scheme adopted by the patent is shown in figures 2 and 3: the light source emitting module of the dual-wavelength multi-polarization laser imaging device consists of a 532nm laser 1, a 1064nm laser 2, a first attenuation plate 3, a second attenuation plate 4, a first linear polarizer 5, a second linear polarizer 6, a first 50:50 beam splitter 7, a second 50:50 beam splitter 8, a first polarization beam splitter 9, a second polarization beam splitter 10, a first diffractive optical element DOE11, a second diffractive optical element DOE12, a first half-wave plate 13, a second half-wave plate 14, a third polarizing beam splitter 15, a fourth polarizing beam splitter 16, a third diffractive optical element DOE17 and a fourth diffractive optical element DOE 18; the polarized photon receiving module of the dual-wavelength multi-polarized laser imaging device is composed of a first receiving telescope 19, a second receiving telescope 20, a first narrow-band filter 21, a second narrow-band filter 22, a fifth polarizing beam splitter 23, a sixth polarizing beam splitter 24, a first optical fiber receiving array 25, a second optical fiber receiving array 26, a third optical fiber receiving array 27, a fourth optical fiber receiving array 28, a first single-photon detector 29, a second single-photon detector 30, a third single-photon detector 31, a fourth single-photon detector 32 and a photon calculating system 33, and the principle is as follows:
1. laser emitted by the 532nm laser 1 is attenuated by the first attenuation sheet 3 and then is adjusted into horizontal polarized light by the first linear polarizer 5; the laser emitted by the 1064nm laser 2 is attenuated by the second attenuator 4 and then is adjusted into horizontal polarized light by the second linear polarizer 6;
2. the horizontal polarization photons reflected by the first 50:50 beam splitter 7 are analyzed and polarized by the first polarization beam splitter 9, and then transmitted, and are divided into linear array horizontal polarization light with 100 beams by the first diffractive optical element DOE11 to be emitted; the horizontal polarized photons reflected by the second 50:50 beam splitter 8 are analyzed and polarized by the second polarization beam splitter 10 and then transmitted, and the horizontal polarized photons are divided into 100 beams by the second diffractive optical element DOE12 and then emitted;
3. the horizontal polarization photons transmitted by the first 50:50 beam splitter 7 are converted into polarization photons in the vertical direction by the first half-wave plate 13, and the polarization photons are detected by the third polarization beam splitter 15 and then reflected out to be divided into linear array vertical polarization photons of 100 beams by the third diffractive optical element DOE17 and then emitted out; the horizontal polarization photons transmitted by the second 50:50 beam splitter 8 are polarization-analyzed by the fourth polarization beam splitter 16 and reflected to linear array vertical polarization photons which are split into 100 beams by the fourth diffractive optical element DOE18, and then emitted as polarization photons which are rotated to the vertical direction by the second half-wave plate 14.
4. After the linear array echo photons reflected by the target are received by the two receiving telescopes, stray light noise is filtered by a narrow-band filter of 532nm or 1064nm, and then horizontal polarization photons and vertical polarization photons are separated through a fifth polarization beam splitter 23 or a sixth polarization beam splitter 24;
5. linear array vertical polarization photons reflected by the reflecting surface of the fifth polarization beam splitter 23 or the sixth polarization beam splitter 24 are coupled to the optical fiber receiving array and enter the first single-photon detector 29 or the second single-photon detector 30 to obtain photon information; linear array horizontal polarization photons transmitted through the transmission surface of the fifth polarization beam splitter 23 or the sixth polarization beam splitter 24 are coupled to the optical fiber receiving array and enter the third single-photon detector 31 or the fourth single-photon detector 32 to obtain photon information;
7. the photon information obtained by the four single-photon detectors is collected and enters the photon calculating system 33, and then the three-dimensional image of the target object containing high-precision distance information and the reflection characteristic of the surface of the target object can be obtained.
The core of this patent lies in: (1) the emitted linear array light source can transmit 532nm and 1064nm linear array lasers with horizontal and vertical polarization directions and based on DOE (do optical element) light splitting 100 beams in a time-sharing manner, the divergence angle between two adjacent beams of lasers is 0.25mrad, and the swath angle of the 100 beams of lasers is about 24.75 mrad. (2) The received 100-beam linear array photons with two polarization states of 532nm and 1064nm in wavelength, horizontal and vertical can be distinguished and counted to obtain four target three-dimensional images with single wavelength and single polarization state of high-precision distance information and the reflection characteristics of the surface of the target.
Compared with the prior art, the advantage of this patent lies in:
1) based on the dual-wavelength multi-polarization laser imaging device, the 100-beam linear array light source with 532nm and 1064nm wavelengths including horizontal and vertical polarization states can be sent in a time-sharing mode, and the capability of receiving multi-wavelength multi-polarization photons and distinguishing and respectively counting the photons is achieved. Four single-wavelength single-polarization point cloud images can be obtained through one-time complete scanning detection, the surface characteristics of the target can be analyzed by comparing the four images obtained through scanning the same target, and whether the surface of the target is a metal material or a non-metal material can be identified.
2) The multi-wavelength multi-polarization single photon magnitude detection technology combines the advantage of high photon counting detection sensitivity with the polarization detection of the target, improves the detection efficiency of the whole system, and realizes the identification of the surface information of the target. And photons in different polarization states are sent in a time-sharing manner, and the echo photon polarization state is counted by utilizing a photon counting system so as to determine the target surface interference condition. The single-photon detector can count the intensity information of the target echo, and the application range of the single-photon detection system can be further enriched by obtaining the surface polarization information of the target. The transmission and the reception of the 100-beam multi-wavelength multi-linear polarized light area array are realized, and a composite three-dimensional information image of a target object containing polarization information is obtained, so that the anti-interference safety detection concept is realized.
Description of the drawings:
FIG. 1 is a system diagram of a dual-wavelength multi-polarization laser imaging device.
Fig. 2 is a schematic diagram of a light source emitting module of a dual-wavelength multi-polarization laser imaging device.
FIG. 3 is a schematic diagram of a polarized photon receiving module of a dual-wavelength multi-polarization laser imaging device.
The specific implementation mode is as follows:
the following further description of the present patent, with reference to the drawings, is provided in fig. 1 to illustrate the structural features and operation of the system and is not intended to limit the scope of the application of the present patent. The specific embodiment of the dual-wavelength multi-polarization laser imaging device comprises the following parts:
(1) the light source emission module: 532nm and 1064nm 100-beam linear array laser with horizontal and vertical polarization respectively is sent to a target object in a time-sharing manner, the divergence angle between two adjacent beams of laser is 0.25mrad, and the swath angle of the 100-beam laser is about 24.75 mrad.
(2) A polarized photon receiving module: echo photons reflected by the target are received by the polarized photon receiving module, and the horizontal polarization and the vertical polarization of 532nm and 1064nm are distinguished and counted respectively to obtain distance information.
(3) Two-dimensional turntable: the device is used for installing a light source transmitting module and a polarized photon receiving module, and the two modules are adjusted to be matched with each other in a transceiving mode and do not have relative displacement when the platform moves. The target object is scanned and detected through the up-and-down swing of the two-dimensional rotary table, so that the rapid three-dimensional imaging of the target object is realized.
In the light source emitting module shown in fig. 2, laser light emitted from a 532nm laser 1 is attenuated by a first attenuator 3 and then is adjusted to be horizontally polarized by a first linear polarizer 5. After passing through a first 50:50 beam splitter (7), the reflected horizontal polarized photons are transmitted after being analyzed and polarized by a first polarization beam splitter 9, and are divided into linear-array horizontal polarized light by a first diffractive optical element DOE11 to be emitted; the transmitted horizontal polarized photons are rotated by the first half-wave plate 13 into vertically polarized photons, which are detected and polarized by the third polarization beam splitter 15, and then reflected out to be divided into linear array vertically polarized photons by the third diffractive optical element DOE17 and emitted out. The laser beam emitted from the 1064nm laser 2 is attenuated by the second attenuator 4 and then is horizontally polarized by the second linear polarizer 6. After passing through the second 50:50 beam splitter 8, the reflected horizontal polarization photons are detected by the second polarization beam splitter 10 and transmitted to be divided into linear array horizontal polarization light by the second diffraction optical element 12 and then emitted; the transmitted horizontal polarized photons are rotated to be polarized in the vertical direction by the second half-wave plate 14, and then reflected out after being analyzed and polarized by the fourth polarization beam splitter (16), and then divided into linear array vertical polarized photons by the fourth diffractive optical element DOE18 to be emitted out.
As shown in the polarization photon receiving module of fig. 3, after stray light noise is filtered by a 532nm first narrow band filter 21 through a part of linear array echo photons reflected by a target object and received by the first receiving telescope 19, a 532nm horizontal polarization photon and a vertical polarization photon are separated by a fifth polarization beam splitter 23; after stray light noise is filtered by the part of the linear array echo photons reflected by the target object, which is received by the second receiving telescope 20, through the 1064nm second narrowband filter 22, the 1064nm horizontal polarization photons are separated from the vertical polarization photons by the sixth polarization beam splitter 24. The linear array vertical polarization photons reflected by the reflecting surface are coupled to the first optical fiber receiving array 25, the second optical fiber receiving array 26 and enter the first single-photon detector 29 and the second single-photon detector 30 to obtain photon information; the linear array horizontal polarization photons transmitted by the transmission surface are coupled to the third optical fiber receiving array 27 and the fourth optical fiber receiving array 28 and enter the third single-photon detector 31 and the fourth single-photon detector 32 to obtain photon arrival information. And summarizing photon information obtained by the four single photon detectors, and entering a photon calculating system 33 to obtain four single-wavelength single-polarization-state target object photon counting imaging graphs.
Claims (6)
1. The utility model provides a dual wavelength multi-polarization laser image device, includes light source emission module, polarization photon receiving module, two dimension revolving stage, its characterized in that:
the light source emitting module sends 100 beam linear array lasers with 532nm and 1064nm wavelengths and horizontal and vertical polarization respectively to a target object in a time-sharing mode, the divergence angle between two adjacent beams of lasers is 0.25mrad, the swath angle of the 100 beam lasers is about 24.75mrad, echo photons reflected by the target object are received by the polarized photon receiving module, and the horizontal polarization and the vertical polarization of 532nm and 1064nm are distinguished and counted respectively to obtain distance information;
the light source emitting module and the polarized photon receiving module are both arranged on a two-dimensional rotary table, the two modules are adjusted to be matched in receiving and sending, relative displacement does not exist when the platform moves, and scanning detection is carried out on a target object through the up-and-down swinging of the two-dimensional rotary table, so that the rapid three-dimensional imaging of the target object is realized, and four target object photon counting imaging images with single wavelength and single polarization state are obtained.
2. The dual wavelength multi-polarization laser imaging device according to claim 1, wherein:
the light source emission module comprises a 532nm laser (1), a 1064nm laser (2), a first attenuation plate (3), a second attenuation plate (4), a first linear polarizer (5), a second linear polarizer (6), a first 50:50 beam splitter (7), a second 50:50 beam splitter (8), a first polarization beam splitter (9), a second polarization beam splitter (10), a first diffractive optical element DOE (11), a second diffractive optical element DOE (12), a first half-wave plate (13), a second half-wave plate (14), a third polarization beam splitter (15), a fourth polarization beam splitter (16), a third diffractive optical element DOE (17) and a fourth diffractive optical element (18);
laser emitted by the 532nm laser (1) is attenuated by the first attenuation sheet (3), then is adjusted to be horizontal line polarized light by the first linear polarizer (5), and passes through the first 50:50 beam splitter (7), reflected horizontal polarized photons are analyzed by the first polarization beam splitter (9) and then are transmitted out, and are divided into linear array horizontal polarized light by the first diffraction optical element DOE (11) and emitted out; the transmitted horizontal polarized photons are rotated into polarized photons in the vertical direction through a first half-wave plate (13), are analyzed and polarized through a third polarization beam splitter (15), are reflected out, are divided into linear array vertical polarized photons through a third diffraction optical element DOE (17), and are emitted out;
the laser emitted by the 1064nm laser (2) is attenuated by the second attenuator (4), then is adjusted to be horizontally polarized light by the second linear polarizer (6), and passes through the second 50:50 beam splitter (8), and then the reflected horizontally polarized photons are analyzed by the second polarization beam splitter (10) and transmitted out to be divided into linear array horizontally polarized light by the second diffractive optical element DOE (12) and emitted out; the transmitted horizontal polarized photons are rotated to be polarized photons in the vertical direction by the second half-wave plate (14), are analyzed and polarized by the fourth polarization beam splitter (16), are reflected out, are divided into linear array vertical polarized photons by the fourth diffraction optical element DOE (18), and are emitted out.
3. The dual wavelength multi-polarization laser imaging device according to claim 1, wherein:
the polarization photon receiving module comprises a first receiving telescope (19), a second receiving telescope (20), a first narrow-band filter (21), a second narrow-band filter (22), a fifth polarization beam splitter (23), a sixth polarization beam splitter (24), a first optical fiber receiving array (25), a second optical fiber receiving array (26), a third optical fiber receiving array (27), a fourth optical fiber receiving array (28), a first single-photon detector (29), a second single-photon detector (30), a third single-photon detector (31), a fourth single-photon detector (32) and a photon calculating system (33);
after the linear array echo photons reflected by the target object are received by the first receiving telescope (19) and stray light noise is filtered by the 532nm first narrow-band optical filter (21), the 532nm horizontal polarization photons and the vertical polarization photons are separated by the fifth polarization beam splitter (23); after the stray light noise is filtered by a second narrow-band filter (22) with the wavelength of 1064nm received by a second receiving telescope (20), a horizontal polarized photon with the wavelength of 1064nm and a vertical polarized photon are separated by a sixth polarization beam splitter (24); the linear array vertical polarization photons reflected by the reflecting surface are coupled to a first optical fiber receiving array (25), a second optical fiber receiving array (26) and enter a first single-photon detector (29) and a second single-photon detector (30) to obtain photon information; linear array horizontal polarization photons transmitted by the transmission surface are coupled to a third optical fiber receiving array (27), a fourth optical fiber receiving array (28) and enter a third single-photon detector (31) and a fourth single-photon detector (32) to obtain photon arrival information; photon information obtained by the four single photon detectors is gathered and enters a photon calculating system (33) to obtain four single-wavelength single-polarization-state target object photon counting imaging graphs.
4. The dual wavelength multi-polarization laser imaging device according to claim 3, wherein:
the first optical fiber receiving array (25), the second optical fiber receiving array (26), the third optical fiber receiving array (27) and the fourth optical fiber receiving array (28) are all composed of 100 multimode optical fibers.
5. The dual wavelength multi-polarization laser imaging device according to claim 3, wherein:
the first single-photon detector (29), the second single-photon detector (30), the third single-photon detector (31) and the fourth single-photon detector (32) are all 100-channel silicon-based Geiger-mode avalanche photodiodes.
6. The dual wavelength multi-polarization laser imaging device according to claim 3, wherein:
the photon resolving system (33) is a 100-channel time-to-digital converter composed of a Field Programmable Gate Array (FPGA) board.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920414456.0U CN209928021U (en) | 2019-03-29 | 2019-03-29 | Dual-wavelength multi-polarization laser imaging device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920414456.0U CN209928021U (en) | 2019-03-29 | 2019-03-29 | Dual-wavelength multi-polarization laser imaging device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN209928021U true CN209928021U (en) | 2020-01-10 |
Family
ID=69071935
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201920414456.0U Active CN209928021U (en) | 2019-03-29 | 2019-03-29 | Dual-wavelength multi-polarization laser imaging device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN209928021U (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109946710A (en) * | 2019-03-29 | 2019-06-28 | 中国科学院上海技术物理研究所 | A kind of more polarized laser imaging devices of dual wavelength |
| CN112526482A (en) * | 2020-11-30 | 2021-03-19 | 北京遥测技术研究所 | Satellite-borne laser near-coast terrain detection laser radar and detection method |
| CN113376653A (en) * | 2021-08-12 | 2021-09-10 | 清华大学 | Photon counting-based three-dimensional imaging method and device for computer-generated holographic radar |
| CN115079203A (en) * | 2022-05-19 | 2022-09-20 | 中国科学院西安光学精密机械研究所 | Non-vision field imaging system and imaging method |
-
2019
- 2019-03-29 CN CN201920414456.0U patent/CN209928021U/en active Active
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109946710A (en) * | 2019-03-29 | 2019-06-28 | 中国科学院上海技术物理研究所 | A kind of more polarized laser imaging devices of dual wavelength |
| CN109946710B (en) * | 2019-03-29 | 2023-12-26 | 中国科学院上海技术物理研究所 | Dual-wavelength multi-polarization laser imaging device |
| CN112526482A (en) * | 2020-11-30 | 2021-03-19 | 北京遥测技术研究所 | Satellite-borne laser near-coast terrain detection laser radar and detection method |
| CN112526482B (en) * | 2020-11-30 | 2024-04-09 | 北京遥测技术研究所 | Satellite-borne laser near-coast terrain detection laser radar and detection method |
| CN113376653A (en) * | 2021-08-12 | 2021-09-10 | 清华大学 | Photon counting-based three-dimensional imaging method and device for computer-generated holographic radar |
| CN115079203A (en) * | 2022-05-19 | 2022-09-20 | 中国科学院西安光学精密机械研究所 | Non-vision field imaging system and imaging method |
| CN115079203B (en) * | 2022-05-19 | 2024-04-12 | 中国科学院西安光学精密机械研究所 | Non-vision imaging system and imaging method |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN209928021U (en) | Dual-wavelength multi-polarization laser imaging device | |
| CN109946710B (en) | Dual-wavelength multi-polarization laser imaging device | |
| CN102169050B (en) | Method for comprehensively measuring reflectivity | |
| US9322992B2 (en) | Devices and methods for multimode light detection | |
| CN107727008B (en) | Device and method for measuring transmitting and receiving coaxiality of active photoelectric system | |
| CN108375762B (en) | Laser radar and working method thereof | |
| CN111536882B (en) | Reading head, two-dimensional displacement measurement system and measurement method | |
| EP4113162A1 (en) | Laser detection system and vehicle | |
| CN104808193A (en) | Non-polarization beam splitter-based Rayleigh scattering Doppler frequency discriminator for F-P (Fabry-Perot) etalons | |
| CN103592652B (en) | Bifrequency Doppler laser radar detection system based on single four marginal technology of solid FP etalons | |
| CN103149158A (en) | Double-prism water quality monitoring optical fiber sensing system | |
| KR20210137567A (en) | LIDAR system with mod field expander | |
| CN102679912A (en) | Auto-collimator based on differential comparison principle | |
| CN109470177B (en) | Three-dimensional angle measuring method and device based on double gratings | |
| CN115494479A (en) | Single photon radar system based on pulse sequence extraction and 3D imaging method | |
| CN105092013B (en) | Sound recognition system and sound identification method | |
| CN107064908A (en) | A kind of multi-wavelength polarizes Raman lidar beam splitting system | |
| CN112346082A (en) | Coherent Doppler wind lidar, method and storage medium | |
| CN201004103Y (en) | Single fiber multi-direction photoelectric module | |
| CN106772312A (en) | A kind of EO-1 hyperion light-dividing device and light-splitting method for Atmospheric Survey | |
| CN1227520C (en) | Long-distance scatterer microvibrating signal measurement and fidelit pickup interferometer | |
| CN112904308B (en) | Laser radar system and method for detecting cloud phase state and cloud water content | |
| CN113671524A (en) | False color laser radar system | |
| CN114063113A (en) | All-fiber non-blind area polarization laser radar system and atmospheric parameter detection method | |
| CN115047431A (en) | Detection device, detector, laser radar and terminal equipment |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |