Patent classifications
G01S7/4812
LINEARIZATION OF CHIRP IN COHERENT LIDAR SYSTEMS
Disclosed herein are systems and methods for linearizing frequency chirp in a frequency-modulated continuous wave (FMCW) coherent LiDAR system. Exemplary methods can include generating a continuous wave laser signal having a frequency characteristic, in which the frequency characteristic can include a frequency chirp over a frequency band in at least one period; and receiving a signal based on the generated laser signal. The methods can further include mixing the received signal with a local oscillator signal, the local oscillator signal having the frequency characteristic; determining at least one beat frequency based on the mixed signal; sampling the mixed signal at a rate equal to at least two times the beat frequency; determining a correction signal based on the sampled signal; and applying the correction signal to the laser signal.
Transmitter optics for a LIDAR system, optical arrangement for a LIDAR system, LIDAR system and working device
A transmitting optical system for a LIDAR system is described for illuminating a field of view with light, having a linear light source for generating and outputting primary light in linear form; and having a deflecting optical system that has a lens assemblage in an intermediate image plane of the deflecting optical system for outputting received primary light into the field of view, and has a deflecting mirror, pivotable one-dimensionally around an axis, for receiving primary light from the linear light source and for directing the primary light onto the lens assemblage and, in that context, imaging the linear light source onto the lens assemblage in such a way that the image of the linear light source sweeps over the lens assemblage, or over a part thereof, upon a pivoting motion of the deflecting mirror.
Patterned mirror edge for stray beam and interference mitigation
A method for optical sensing includes providing a mirror comprising a central reflective region surrounded by a peripheral glare-suppressing region. A beam of light from a laser light source is directed to reflect from the central region so as to pass through an output optic along an axis toward a target scene. The light returned from the target scene through the output optic is focused onto an optical sensor, via collection optics having a collection aperture surrounding the mirror.
TECHNIQUES FOR PROCESSING A TARGET RETURN SIGNAL USING FREE-SPACE OPTICS
Free-space optics for use in a light detection and ranging (LIDAR) apparatus include a polarization beam-splitter (PBS) to direct an optical beam in a first direction toward a target environment and to propagate a portion of the optical beam in a second direction for receipt by a photodetector (PD), a polarization wave plate (PWP) to convert the optical beam from a first polarization to a second polarization, and to convert the target return signal from a third polarization to a fourth polarization, and a lens system coupled between the PBS and the PWP to magnify the optical beam. The propagated portion of the optical beam comprises a local oscillator (LO) signal to mix with a target return signal to generate target information.
Perturbations external to a laser cavity
A laser system includes a resonant laser cavity configured to output a laser signal. The system also includes a utility waveguide configured to receive the laser signal from the laser cavity. The utility waveguide includes a perturbation region that is external to the laser cavity and receives the laser signal from the laser cavity and outputs a laser beam. The perturbation region includes one or more perturbation structures that each causes one or more perturbation(s) in the index of refraction of the utility waveguide. The perturbation structures are selected to provide optical feedback to the resonant laser cavity such that a power versus wavelength distribution in the laser beam is different from the power versus wavelength distribution that would be in the laser signal in the absence of the perturbation structures.
Photonic circulator for a LiDAR device
A photonic circulator deployed on a chip-scale light-detection and ranging (LiDAR) device includes a first arm that includes a first waveguide that is bonded onto a first member at a first bonding region, and a second arm that includes a second waveguide that is bonded onto a second member at a second bonding region. A first thermo-optic phase shifter is arranged on the first member and collocated with the first waveguide, and a second thermo-optic phase shifter is arranged on the second member and collocated with the second waveguide. The magneto-optic material and the first thermo-optic phase shifter of the first member cause a first phase shift in a first light beam travelling through the first waveguide, and the magneto-optic material and the second thermo-optic phase shifter of the second member cause a second phase shift in a second light beam travelling through the second waveguide.
TECHNIQUES FOR PROCESSING AMPLITUDE MODULATION (AM) AND FREQUENCY MODULATION (FM) IN SEPARATE PATHS FOR SIMULTANEOUS DETERMINATION OF RANGE AND VELOCITY IN AN FMCW LIDAR SYSTEM
A light detection and ranging (LIDAR) system has a modulator to modulate a light signal from an optical source with a low-power mode at a section of a sweep signal to generate a pulsed light signal transmitted towards a target. The LIDAR system has a photodetector to receive a return beam from the target with an amplitude modulated (AM) signal portion and a frequency modulated (FM) signal portion. The LIDAR system processes the return beam with in-phase/quadrature (I/Q) detection to extract the AM signal portion and the FM signal portion. The system determines a range value and a velocity value for the target based on the extracted AM signal portion and the extracted FM signal portion.
Kinematic mount for active MEMS alignment with multi-degree-of-freedom comprising plural spring-loaded posts
A MEMS board assembly, a LiDAR system including the same, and a method for making the same are disclosed. The exemplary MEMS board assembly includes a MEMS board having a plurality of through holes and a mount having a plurality of threaded holes. The MEMS board assembly further includes a plurality of spring-loaded posts each formed by fitting a spring into a respective post. The plurality of spring-loaded posts are fitted into the plurality of threaded holes of the mount. The MEMS board assembly also includes a plurality of screws fitting the MEMS board to the mount by reaching into the plurality of threaded holes of the mount through the plurality of through holes in the MEMS board and the plurality of spring-loaded posts. The MEMS board touches the plurality of spring-loaded posts at the plurality of through holes in the MEMS board corresponding to the plurality of threaded holes of the mount respectively.
DETECTION AND RANGING SYSTEMS EMPLOYING OPTICAL WAVEGUIDES
An optical waveguide has at least two major external surfaces and is configured for guiding light by internal reflection, and is deployed with one of the two major external surfaces in facing relation to a scene. An optical coupling-out configuration is associated with the optical waveguide and is configured for coupling a proportion of light, guided by the optical waveguide, out of the optical waveguide toward the scene. An illumination arrangement is deployed to emit light for coupling into the optical waveguide that is collimated prior to being coupled in the optical waveguide. A detector is configured for sensing light reflected from an object located in the scene in response to illumination of the object by light coupled out of the optical waveguide by the optical coupling-out configuration. A processing subsystem is configured to process signals from the detector to derive information associated with the object.
Optical Device
An optical device includes a range finding module. The range finding module includes a first light condenser unit, a light emitting unit and a light receiving unit. The first light condenser unit defines an optical axis and a hole disposed along the optical axis. The first light condenser unit, the light emitting unit and the light receiving unit are sequentially arranged along the optical axis. The light is emitted by the light emitting unit, passes through the hole, reaches an object, is reflected by the object, is converged by the first light condenser unit and is received by the light receiving unit to generate an electrical signal.