Scan-less 3D optical sensing devices and associated lidar based on stacking of integrated photonic chips, wavelength division demultiplexing and position-to-angle conversion of a lens

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

• a plurality of different photonic chips formed on separate substrates, respectively, wherein the different photonic chips are engaged and stacked with one another and each photonic chip carries laser light at different laser wavelengths;
• and
• a lens spaced from the different photonic chips and shared by the different photonic chips to receive light from the different photonic chips and to direct returned light back to the different photonic chips,
• wherein each photonic chip includes:
• an optical circulator or coupler supported by a corresponding substrate to receive an optical beam of laser light at different laser wavelengths and re-direct the optical beam;
• a first wavelength division demultiplexing device supported by the substrate to receive the optical beam from the optical circulator or coupler and to separate the received optical beam into different optical beams at the different laser wavelengths, respectively;
• an array of optical waveguides supported by the substrate and structured to include first waveguide ports, respectively, which are coupled to receive the different optical beams at the different laser wavelengths, respectively, from the first wavelength division demultiplexing device, and second waveguide ports, respectively, which output the different optical beams at the different laser wavelengths received by the optical waveguides as different output optical beams at the different laser wavelengths, respectively, wherein each optical waveguide is designed to carry light at a designated laser wavelength of the different laser wavelengths;
• wherein the lens shared by the different photonic chips is spaced from the second waveguide ports by a distance equal to or near a focal length of the lens to receive the different output optical beams at the different laser wavelengths, respectively, to direct each output optical beam to a unique beam direction based on a position of a corresponding second waveguide port of the each waveguide relative to the lens so that each output optical beam directed from each of the differently located second waveguide ports is directed by the lens to a different direction after passing through the lens, wherein the lens is further operable to receive and direct returned light at the different laser wavelengths to the second waveguide ports, respectively, so that each waveguide used to carry a designated laser wavelength is to receive and direct a returned optical beam at the same designated laser wavelength to the first wavelength division demultiplexing device which combines different returned optical beams at the different laser wavelengths as a combined returned beam of light at the different laser wavelengths to the optical circulator or coupler;
• a second wavelength division demultiplexing device supported by the substrate and located relative to the optical circulator or coupler to receive the combined returned beam from the optical circulator or coupler, wherein the second wavelength division demultiplexing device is operable to separate the combined returned beam into different returned optical beams at the different laser wavelengths, respectively;
• and
• an optical detector array of photodetectors supported by the substrate and coupled to receive the different returned optical beams at the different laser wavelengths from the second wavelength division demultiplexing device, respectively, to produce different detector output signals from the different returned optical beams at the different laser wavelengths for optical sensing.