CN-224231976-U - Underwater laser radar

CN224231976UCN 224231976 UCN224231976 UCN 224231976UCN-224231976-U

Abstract

The underwater laser radar is characterized by comprising a transmitting module, a receiving module and a driving IC, wherein the transmitting module comprises a laser, a collimating mirror, a micro lens array and a projection lens, the laser is used for transmitting blue light and/or green light speckle, the collimating mirror is positioned on an emergent light path of the laser and is used for collimating the light path, one side of the micro lens array is a plane, the other side of the micro lens array comprises micro lenses which are arranged randomly, the average distance of the micro lenses is smaller than the diameter, the boundaries of the micro lenses are overlapped, the object plane of the projection lens is conjugated with the focal plane of the micro lens array, the speckle pattern of the focal plane is projected to form the speckle pattern, the receiving module receives a reflected signal of the speckle pattern, and the driving IC comprises a triggering circuit which can simultaneously turn on and off the laser and the receiving module. The utility model effectively improves the accuracy of underwater modeling and obstacle avoidance and the suitability of the underwater modeling and obstacle avoidance to different application scenes.

Inventors

HUANG RUIBIN
LV FANGLU
ZHU LI
WANG BO

Assignees

深圳市光鉴科技有限公司
重庆光鉴傲深科技有限公司

Dates

Publication Date: 20260512
Application Date: 20250427

Claims (10)

1. An underwater laser radar is characterized by comprising a transmitting module, a receiving module and a driving IC, wherein, The emission module comprises a laser, a collimating mirror, a micro lens array and a projection lens; the laser is used for emitting blue light and/or green light speckle; The collimating mirror is positioned on an emergent light path of the laser and is used for collimating the light path; One side of the micro lens array is a plane, the other side of the micro lens array comprises micro lenses which are arranged randomly, the average distance between the micro lenses is smaller than the diameter, and the boundaries of the micro lenses are overlapped; The object plane of the projection lens is conjugate with the focal plane of the micro lens array, and the speckle pattern of the focal plane is projected out to form a speckle pattern; The receiving module receives the reflected signal of the speckle pattern; The driving IC comprises a trigger circuit, and can simultaneously turn on and off the laser and the receiving module.
2. The underwater lidar of claim 1, further comprising a prism between the collimator lens and the microlens array, wherein a slant surface is coated with a metal film or a highly reflective dielectric film for changing the direction of the optical path.
3. The underwater lidar of claim 1, further comprising a circuit board, wherein the circuit board, the driving IC, and the transmitting module are mounted on a single circuit board through a common substrate.
4. The underwater lidar of claim 1, further comprising a gradation attenuation sheet for gradually changing the brightness of the speckle.
5. An underwater lidar as in claim 1 wherein the laser emits light with TE mode polarization and degree of polarization DOP >95%.
6. The underwater lidar of claim 1, wherein the laser is an edge-emitting semiconductor laser with a wavelength in the range of 430-470 nm.
7. The underwater lidar of claim 1, wherein the receiving module comprises: The receiving lens is used for collecting reflected light; The narrow-band polarizing filter is positioned on the light path of the receiving lens and is used for enabling light of a specific wave band to pass through; and the SPAD sensor is used for receiving the light passing through the narrow-band polarized filter.
8. The underwater lidar of claim 7, wherein the FOV of the receiving lens is the same as the FOV of the projection lens.
9. The underwater lidar of claim 7, wherein the narrow-band polarizing filter has a metal wire grid on a side close to the receiving lens, so as to filter light rays and transmit light rays with a specific polarization direction.
10. The underwater lidar of claim 7, wherein the narrow-band polarizing filter is coated with a multi-layer dielectric film on a side close to the SPAD sensor, so that light rays with a specific wavelength can pass through the multi-layer dielectric film, and light rays with other wavelengths can be blocked.

Description

Underwater laser radar Technical Field The utility model relates to the technical field of laser radars, in particular to an underwater laser radar. Background In underwater unmanned equipment such as swimming pool cleaning robots and submarines, an ultrasonic sensor is generally used for realizing environmental perception and obstacle avoidance. Ultrasonic sensors, although widely used, have some limitations. Comprising the following steps: Environmental factors the measurement accuracy of the ultrasonic sensor may be affected by temperature, environmental noise, etc. The soft materials influence that the soft materials such as fabrics, pasture and water, jellyfish and the like in water and tiny objects have slight refraction deviation on sound waves, and obvious reflection cannot be formed, so that a receiver is difficult to detect a target. Measurement accuracy-the measurement accuracy of ultrasonic sensors is typically in the order of centimeters and may not be accurate enough for applications requiring higher accuracy. The beam angle of the ultrasonic sensor is large, the directivity is poor, which may cause instability of ranging. The foregoing background is only for the purpose of providing an understanding of the inventive concepts and technical aspects of the present utility model and is not necessarily prior art to the present application and is not intended to be used as an aid in the evaluation of the novelty and creativity of the present application in the event that no clear evidence indicates that such is already disclosed at the filing date of the present application. Disclosure of utility model Therefore, the utility model provides the underwater laser radar which uses the blue light polarization laser as a light source, has the advantages of high environmental adaptability, capability of measuring flexible objects, high measurement precision and stable underwater penetration distance, and can be applied to underwater unmanned equipment such as swimming pool cleaning robots, underwater vehicles and the like to effectively improve the precision of underwater modeling and obstacle avoidance and the suitability for different application scenes. The utility model provides an underwater laser radar, which is characterized by comprising a transmitting module, a receiving module and a driving IC, wherein, The emission module comprises a laser, a collimating mirror, a micro lens array and a projection lens; the laser is used for emitting blue light and/or green light speckle; The collimating mirror is positioned on an emergent light path of the laser and is used for collimating the light path; One side of the micro lens array is a plane, the other side of the micro lens array comprises micro lenses which are arranged randomly, the average distance between the micro lenses is smaller than the diameter, and the boundaries of the micro lenses are overlapped; The object plane of the projection lens is conjugate with the focal plane of the micro lens array, and the speckle pattern of the focal plane is projected out to form a speckle pattern; The receiving module receives the reflected signal of the speckle pattern; The driving IC comprises a trigger circuit, and can simultaneously turn on and off the laser and the receiving module. Optionally, the underwater laser radar is characterized by further comprising a prism, wherein the prism is positioned between the collimating mirror and the micro lens array, and the inclined plane is plated with a metal film or a high-reflection dielectric film and is used for changing the direction of a light path. Optionally, the underwater laser radar is characterized by further comprising a circuit board, wherein the circuit board, the driving IC and the transmitting module are attached to one circuit board through a common substrate. Optionally, the underwater laser radar is characterized by further comprising a gradual attenuation sheet, wherein the gradual attenuation sheet is used for gradually changing the brightness of the speckles. Optionally, the underwater laser radar is characterized in that the light emitted by the laser is polarized light of TE mode, and the degree of polarization DOP is more than 95%. Optionally, the underwater laser radar is characterized in that the laser is an edge-emitting semiconductor laser, and the wavelength range is 430-470 nm. Optionally, the underwater laser radar is characterized in that the receiving module includes: The receiving lens is used for collecting reflected light; The narrow-band polarizing filter is positioned on the light path of the receiving lens and is used for enabling light of a specific wave band to pass through; and the SPAD sensor is used for receiving the light passing through the narrow-band polarized filter. Optionally, the underwater laser radar is characterized in that the FOV of the receiving lens is the same as the FOV of the projection lens. Optionally, the underwater laser radar is characterized i