Systems and methods for lidar scanning of an environment over a sweep of wavelengths
AssigneeSantec Corporation
InventorChangho CHONG
Life of this patent
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Abstract
A LIDAR sensing system includes a light source that is controlled to project a collimated beam at various wavelengths. An interferometer receives the collimated beam and projects an object beam corresponding to the collimated beam at a diffraction grating. The object beam is diffracted from the diffraction grating at different angles corresponding to the wavelength of the collimated beam, creating a two dimensional scan along a first axis. The object beam is also controlled along a second axis that is perpendicular to the first axis. As a result, the LIDAR sensing system generates a horizontal and vertical scan (e.g., a three-dimensional scan) of the external environment.
Claims20
A LIDAR sensing system, comprising:
- a light source arranged to project a collimated beam along a path, the light source configured to continuously sweep the projected collimated beam across frequencies from a first frequency to a last frequency;
- a beam splitting device that splits the collimated beam into 1) a reference beam and 2) an object beam that is directed into an external environment of the LIDAR sensing system;
- a wavelength dispersive element arranged along the path of the object beam, the wavelength dispersive element configured to project the object beam into the external environment at a plurality of diffraction angles relative to a first axis based on the frequency of the collimated beam;
- and
- a detector system that continuously detects, over the frequencies from the first frequency to the last frequency, interference patterns generated by the beam splitting device and corresponding to 1) light reflected off objects located in the external environment and 2) the reference beam.
A method of LIDAR sensing, the method comprising:
- controlling a light source to project a swept-frequency collimated beam that is continuously swept from a first frequency to a last frequency, the swept-frequency collimated beam being projected towards a wavelength dispersive element;
- splitting, via a beam splitting device, the swept-frequency collimated beam into a reference beam and an object beam;
- diffracting, via the wavelength dispersive element, the object beam into the external environment at one of multiple diffraction angles according to the frequency of the swept-frequency collimated beam, wherein the object beam is diffracted from the wavelength dispersive element at continuously-swept diffraction angles as the frequency of the swept-frequency collimated beam is swept from a first diffraction angle, when the collimated beam is projected at the first frequency, to a last diffraction angle when the collimated beam is projected at the last frequency, wherein the first diffraction angle and the last diffraction angle define a field of view along a first axis;
- and
- continuously calculating distances associated with objects located within the field of view based on interference patterns generated based on 1) light corresponding to the object beam being reflected off objects in the external environment and 2) the reference beam reflected off a reference mirror.
Dependencies are inferred from the claim text.