An optical testing apparatus is used in testing an optical measuring instrument that provides incident light from a light source to an incident object and receives reflected light of the incident light at the incident object. The apparatus includes an incident light receiving section, a light signal providing section, an imaging section, and an optical axis misalignment deriving section. The incident light receiving section receives incident light. The light signal providing section provides a light signal to an incident object after a predetermined delay time since the incident light receiving section has received the incident light. The imaging section images the incident light. The optical axis misalignment deriving section derives misalignment of the optical axis of the incident light with respect to the incident light receiving section based on misalignment between the incident light receiving section and the imaging section as well as an imaging result with the imaging section.

A coherent LIDAR imaging system includes a laser source; an optical splitter/recombiner designed to split the laser radiation into a reference beam and into an object beam and to superpose the reference beam on a reflected object beam reflected by the scene; and an optical imager creating an image of the scene on a detector. The detector includes an array of pixels designed for detecting the reflected object beam and the reference beam which together form a recombined beam having a beat frequency representative of a range of the illuminated scene. The optical splitter/recombiner is configured to form an intermediate image of the reference beam in an intermediate image plane perpendicular to the optical axis.

A dual lens assembly positioned along an optical receive path within a LiDAR system is provided. The dual lens assembly is constructed to reduce a numerical aperture of a returned light pulse and reduce a walk-off error associated with one or more mirrors of the LiDAR system.

Aspects of the present disclosure describe large scale steerable optical switched arrays that may be fabricated on a common substrate including many thousands or more emitters that may be arranged in a curved pattern at the focal plane of a lens thereby allowing the directional control of emitted light and selective reception of reflected light suitable for use in imaging, ranging, and sensing applications including accident avoidance.

An integrated optical beam steering device includes a planar Luneburg lens that collimates beams from different inputs in different directions within the lens plane. It also includes a curved (e.g., semi-circular or arced) grating coupler that diffracts the collimated beams out of the lens plane. The beams can be steered in the plane by controlling the direction along which the lens is illuminated and out of the plane by varying the beam wavelength. Unlike other beam steering devices, this device can operate over an extremely wide field of view—up to 180°—without any aberrations off boresight. In other words, the beam quality is uniform in all directions, unlike with aplanatic lenses, thanks to the circular symmetry of the planar Luneburg lens, which may be composed of subwavelength features. The lens is also robust to misalignment and fabrication imperfections and can be made using standard CMOS processes.

A LiDAR system has a field of view and includes a polarization-based waveguide splitter. The splitter includes a first splitter port, a second splitter port and a common splitter port. A laser is optically coupled to the first splitter port via a single-polarization waveguide. An objective lens optically couples each optical emitter of an array of optical emitters to a respective unique portion of the field of view. An optical switching network is coupled via respective dual-polarization waveguides between the common splitter port and the array of optical emitters. An optical receiver is optically coupled to the second splitter port via a dual-polarization waveguide and is configured to receive light reflected from the field of view. A controller, coupled to the optical switching network, is configured to cause the optical switching network to route light from the laser to a sequence of the optical emitters according to a temporal pattern.

A first light source outputs measurement light having a wavelength in infrared range. A second light source outputs guide light having a wavelength in visible range. A fiber coupler includes a first port into which the measurement light is input, a second port into which the guide light is input, and a third port outputting combined light formed by combining the measurement light and the guide light with each other. A measurement unit emits the combined light to a measurement object and receives return light reflected therefrom. A processing unit obtains information relating to a distance, a speed, or an oscillation of the measurement object, based on an interference signal of the return light and the reference light. The fiber coupler is formed by a single mode fiber that has a cutoff wavelength that is shorter than that of the measurement light and longer than that of the guide light.

A system for precision displacement measurement based on a self-traceable grating interference includes a coherent light source, a photoelectric detection module, a self-traceable grating and a signal processing module. The self-traceable grating is arranged on a to-be-measured displacement motion platform. The coherent light source, the photoelectric detection module and the signal processing module are sequentially connected. Laser generated by the coherent light source propagates through the photoelectric detection module and is incident on the self-traceable grating, diffracts with the self-traceable grating, returns to the photoelectric detection module to continue propagating and enters the signal processing module. The signal processing module collects an interference signal to obtain a motion displacement and a motion direction.

An optical scanning device includes an optical mode converter to change, in accordance with a change in wavelength of a light output from a light source or phase of the light output from the light source, a radiation direction of the light, and an actuator to rotate the optical mode converter about each of two shafts orthogonal to each other.

A holographic waveguide LIDAR having a transmitter waveguide coupled to a beam deflector and a receiver waveguide coupled to a detector module. The transmitter waveguide contains an array of grating elements for diffracting a scanned laser beam into a predefined angular ranges. The receiver waveguide contains an array of grating elements for diffracting light reflected from external points within a predefined angular range towards the detector module.