Optical beam scanning based on waveguide switching and position-to-angle conversion of a lens and applications

A light detection and ranging (LiDAR) device, comprising:

• a light source to produce an optical beam that includes laser light at different laser wavelengths;
• a beam scanning device located in an optical path of the optical beam to direct and scan the optical beam to a surrounding area for LiDAR sensing and to receive returned light from the surrounding area illuminated by the optical beam;
• an optical circulator located in the optical path between the light source and the beam scanning device to direct the optical beam from the light source to the beam scanning device and to receive and direct the returned light received by the beam scanning device as a detected returned beam that is separate from the optical beam from the light source;
• a wavelength division multiplexing device to receive the detected returned beam from the optical circulator and to separate the detected returned beam into different detected optical beams at the different laser wavelengths;
• an optical detector array of photodetectors coupled to receive the different detected optical beams at the different laser wavelengths from the wavelength division multiplexing device, respectively, to produce different detector output signals from the different detected optical beams at the different laser wavelengths for LiDAR sensing,
• wherein the beam scanning device is structured to include:
• a wavelength division demultiplexing device to receive the optical beam from the light source that includes laser light at the different laser wavelengths from the optical circulator and to separate the received optical beam into different optical beams at the different laser wavelengths, respectively;
• an array of optical waveguides coupled to receive the different optical beams at the different laser wavelengths, respectively, from the wavelength division demultiplexing device;
• optical couplers formed at different locations adjacent to the optical waveguides so that each optical waveguide is designated with, and corresponds to, a plurality of optical couplers along the each optical waveguide, each optical coupler structured to receive light from a corresponding optical waveguide and to direct the received light out of a plane of the substrate;
• optical switches formed at different locations adjacent to the optical waveguides so that each optical waveguide is designated with, corresponds to, a plurality of optical switches along the each optical waveguide, wherein each optical switch is coupled to a designated optical waveguide to either direct light out of the designated optical waveguide or to maintain the light in the designated optical waveguide, and each optical switch is located and paired to a designated optical coupler and structured to couple light from a corresponding designated optical waveguide to the paired designated optical coupler which directs light from the each optical switch out of a plane of the optical waveguides as an optical output beam;
• and
• a lens spaced from the plane of the optical waveguides by a distance equal to or near a focal length of the lens to receive the optical output beam from the optical couplers to direct the optical output beam from each optical coupler to a unique beam direction based on a position of the optical relative to the lens so that the optical output beam directed from different optical couplers is directed by the lens to different directions by the lens.