Patent classifications
G01S7/491
Method of measuring a change in an optical path length using differential laser self-mixing interferometry and a differential laser self-mixing interferometry measuring system
A method and system to implement the method of measuring a change in an optical path length using differential laser self-mixing interferometry. The method includes obtaining a reference SMI signal (Sr) and a main measurement SMI signal (Sm) of a laser (LD) and determining the relative change in the optical path length between the (LD) and a target (T) in a range between 0 and λ/2, by comparing the relative positions along time of fringes or transitions of the (Sm) and (Sr). The (Sr) and the (Sm) are obtained at different moments once backscattered laser light (br) is generated from the reflection on said target (T) of a reference and a main measurement laser light beam emitted by the laser (LD) and while being modulated according to a specific modulation pattern that maintained while both the (Sr) and the (Sm) are acquired and has re-entered its laser cavity.
DISTANCE SENSOR AND IMAGE PROCESSING SYSTEM INCLUDING THE SAME
A pixel of a distance sensor includes a photosensor that generates photocharges corresponding to light incident in a first direction. The photosensor includes a plurality of first layers having a cross-sectional area increasing along the first direction after a first depth and at least one transfer gate which receives a transfer control signal for transferring the photocharges to a floating diffusion node. A strong electric field is formed in the direction in which the photocharges move horizontally or vertically in the pixel, thereby accelerating the photocharges, allowing for increased sensitivity and demodulation contrast.
Depth from time of flight camera
Region of interest detection in raw time of flight images is described. For example, a computing device receives at least one raw image captured for a single frame by a time of flight camera. The raw image depicts one or more objects in an environment of the time of flight camera (such as human hands, bodies or any other objects). The raw image is input to a trained region detector and in response one or more regions of interest in the raw image are received. A received region of interest comprises image elements of the raw image which are predicted to depict at least part of one of the objects. A depth computation logic computes depth from the one or more regions of interest of the raw image.
Radar apparatus and method of determining sign of velocity
A radar apparatus which can simply determine the sign of velocity of an object is provided. Laser light reflected by the object undergoes quadrature optical heterodyne detection performed by mixers, optical detectors, and a π/2 phase shifter, whereby I and Q component signals are output. A frequency analyzer performs FFT on a complex signal composed of the I component signal (real part) and the Q component signal (imaginary part) to thereby obtain its frequency spectrum. Since the frequency spectrum is calculated without being folded back even in a region where the frequency is negative, the sign of the Doppler frequency fd can be determined. When the Doppler frequency fd is positive, the sign of the velocity of the object is a direction toward the radar apparatus. When the Doppler frequency fd is negative, the sign of the velocity of the object is a direction away from the radar apparatus.
Device for determining wind speed comprising a plurality of laser sources
This device for determining wind speed comprises at least two laser sources emitting beams in different directions that are coplanar and such that each emission direction corresponds to a perpendicular emission direction. Each laser source is associated with focusing optics for focusing the emitted beam, a laser diode for receiving a reflected beam obtained after reflection by a particle present in the air of the corresponding emitted beam, a photodiode for transmitting an interference signal occurring between the emitted beam and the reflected beam, a processor for processing the obtained interference signals, and an optical cavity into which the reflected beam is reinjected in order to obtain an interference with the emitted beam.
Human body detection sensor and automatic faucet
A human body detection sensor includes: a detection decision unit that decides whether a state is a detection state or a non-detection state of a detection target; a specular reflection decision unit that decides whether or not reflected light that is incident onto a line sensor is specularly-reflected light; and a continuation decision unit that decides whether or not a state in which the detection target exists is ongoing, wherein, when specularly-reflected light is detected while a determination is made indicating the detection state, the detection decision unit keeps the result of a determination indicating the detection state without change if the result of the decision by the continuation decision unit indicates that the state is ongoing and changes the determination to a determination indicating the non-detection state if the result of the decision shows any other states.
ACTIVE IMAGING USING A MICRO-ELECTRO-MECHANICAL SYSTEM (MEMS) MICRO-MIRROR ARRAY (MMA)
Imaging systems and method of optical imaging. One example of an imaging system includes an optical scanning subsystem including an optical source and a MEMS MMA, the MEMS MMA being configured to direct optical radiation generated by the optical source over an area of a scene, a detection subsystem including an optical sensor configured to collect reflected optical radiation from the area of the scene, and a fused fiber focusing assembly including a fused fiber bundle, a plurality of lenses coupled together and positioned to receive and focus the reflected optical radiation from the area of the scene directly onto the fused fiber bundle, a microlens array interposed between the fused fiber bundle and the optical sensor and positioned to receive the reflected optical radiation from the fused fiber bundle, and a focusing lens positioned to direct the reflected optical radiation from the microlens array onto the optical sensor. The MEMS MMA may be further configured to generate and independently steer multiple beams of optical radiation, at the same or different wavelengths, to more fully interrogate the area of the scene. The MEMS MMA through its Piston capability may be further configured to shape the optical beam(s) to execute a variety of optical functions within the beam steering device.
Methods and Systems for Dithering Active Sensor Pulse Emissions
One example device comprises a plurality of emitters including at least a first emitter and a second emitter. The first emitter emits light that illuminates a first portion of a field-of-view (FOV) of the device. The second emitter emits light that illuminates a second portion of the FOV. The device also comprises a controller that obtains a scan of the FOV. The controller causes each emitter of the plurality of emitters to emit a respective light pulse during an emission time period associated with the scan. The controller causes the first emitter to emit a first-emitter light pulse at a first-emitter time offset from a start time of the emission time period. The controller causes the second emitter to emit a second-emitter light pulse at a second-emitter time offset from the start time of the emission time period.
LIDAR IMAGING SYSTEM WITH FMCW TYPE HETERODYNE DETECTION COMPRISING A DEVICE FOR CORRECTING THE PHASE OF THE REFERENCE SIGNAL
The invention relates to a LIDAR imaging system of the FMCW type, comprising a light source (10), an optical projection device (20), an optical transmission device (30), an optical imaging device (40), and a matrix photodetector (50). It further comprises a phase correction device (60) comprising a spatial phase modulator (61) for applying a corrected spatial phase distribution to the reference signal, and a computation unit (62) for determining the corrected spatial phase distribution, by taking into account a spatial distribution representing a spatial intensity distribution of the backscattered object signal, so that the reference signal has a corrected spatial intensity distribution in the reception plane optimizing a spatial distribution of a parameter of interest representing the heterodyne signal.
LIDAR ASSEMBLY WITH MODULARIZED COMPONENTS
Embodiments of the disclosure provide an interface module for a LiDAR assembly. The interface module includes a printed circuit board (PCB) and a first connector interface disposed on the PCB. The first connector interface is configured to be connectable to a laser emitter of the LiDAR assembly. The interface module further includes a second connector interface disposed on the PCB and a third connector interface disposed on the PCB. The second connector interface is configured to be connectable to a receiver of the LiDAR assembly and the third connector interface is configured to be connectable to a control module configured to control the operation of the laser emitter and the receiver. The interface module also includes a bracket where the PCB is affixed to. The interface module is positioned to a lateral face of the LiDAR assembly through the bracket.