A two-degree-of-freedom heterodyne grating interferometry measurement system, comprising: a single-frequency laser device for emitting a single-frequency laser, and the single-frequency laser can be split into a beam of reference light and a beam of measurement light; an interferometer mirror group and a measurement grating for forming a reference interference signal and a measurement interference signal from the reference light and the measurement light; and a receiving optical fiber for receiving the reference interference signal and the measurement interference signal, wherein a core diameter of the receiving optical fiber is smaller than a width of an interference fringe of the reference interference signal and the measurement interference signal, so that the receiving optical fiber receives a part of the reference interference signal and the measurement interference signal. The measurement system has advantages of insensitivity to grating rotation angle error, small volume, light weight, and a facilitating arrangement.

Optical coherent receiver arrays are described. The optical coherent receiver arrays include an integrated array of photodetectors separated by integrated mirrors which may cause interference of received free space optical and local oscillator signals. The mirrors may serve as splitters, helping to align the received signal and local oscillator to cause interference. The photodetectors of the optical coherent receiver array may be electrically coupled in various manners to read out the signals. The optical coherent receiver array may be implemented in an optical coherence tomography (OCT) imaging system in some embodiments.

In an optical device, an elastic support unit includes a pair of levers which face in a second direction perpendicular to a first direction, a pair of first torsion support portions which are connected between the levers and the base, a pair of second torsion support portions which are connected between the pair of levers and the movable unit, and a first link member that bridges the levers. The levers and the first link member define a light passage opening. Each of connection positions between the levers and the first torsion support portions is located on a side opposite to the movable unit with respect to the center of the light passage opening in a third direction perpendicular to the first direction and the second direction. A maximum width of the light passage opening in the second direction is defined by a gap between the levers in the second direction.

A digital measuring device implemented on a photonic integrated circuit, the digital measuring device including a laser source implemented on the photonic integrated circuit configured to provide light, a first waveguide structure implemented on the photonic integrated circuit configured to direct a first portion of light from the laser source at a moving object and receive light reflected from the moving object, a second waveguide structure implemented on the photonic integrated circuit configured to combine a second portion of light from the laser source with the light reflected from the moving object to produce a measurement beam, a first multiplexer implemented on the photonic integrated circuit configured to split the measurement beam into a plurality of channels, and a plurality of detectors implemented on the photonic integrated circuit configured to detect an intensity value of each channel to measure a distance between the digital measuring device and the moving object.

A digital measuring device implemented on a photonic integrated circuit, the digital measuring device including a laser source configured to provide light, a first ring resonator configured to produce a first frequency comb of light from the laser source, wherein at least a portion of the first frequency comb of light is directed at a moving object, a local oscillator configured to provide a reference beam, at least one waveguide structure configured to combine the reference beam with light reflected from the moving object to produce a measurement beam, a first multiplexer configured to split the measurement beam into a plurality of channels spaced in frequency, and a plurality of detectors configured to detect an intensity value of each channel of the plurality of channels to measure a distance between the digital measuring device and the moving object.

There is described an interferometer for use in an optical locker. The interferometer comprises at least two transparent materials having different thermal path length sensitivities. The interferometer is configured such that an input beam is split by the interferometer into first and second intermediate beams, which recombine to form an output beam, the first and second intermediate beams travelling along respective first and second intermediate beam paths which do not overlap. At least one of the intermediate beam paths passes through at least two of the transparent materials. A length of each intermediate beam path which passes through each transparent material is selected such that an optical path difference between the first and second intermediate beam path is substantially independent of temperature.

The present invention relates to a housing of a Michelson interferometer that may facilitate optical alignment of a plurality of optical components by applying a two-part structured housing to the Michelson interferometer. The present invention may provide a Michelson interferometer housing system including a first housing including a first surface on which a fixed mirror is installed, a second surface perpendicular to the first surface, and a first diagonal surface on which a beam splitter assembly to which light is incident from the outside is installed, the first diagonal surface being formed at 45 degrees with respect to the second surface; and a second housing including a third surface on which a movable mirror is installed, a fourth surface perpendicular to the third surface, and a second diagonal surface corresponding to the first diagonal surface, wherein the first and second housings are combined such that the first and second diagonal surfaces face each other to allow the light entering from the outside to be divided through the beam splitter assembly and incident to the fixed mirror and the movable mirror.

An interferometer includes a coherent light source and an array of electrically coupled light-sensitive pixel elements. The interferometer is configured to direct an internal optical path of the coherent light source and an external optical path of the coherent light source into a monolithic unit cell. In addition, the monolithic unit cell is configured to direct the internal optical path first through the monolithic unit cell and then onto the array and also configured to direct the external optical path back outside the monolithic unit cell through an external environment and then back into the monolithic unit cell and finally onto the array. In addition, interferometer is further configured to combine the internal optical path and the external optical path at the array and produce a first interferogram on the array, the interferogram characterizing an optical property of the external environment.

An optical component for an attenuated total reflection interferometric imaging device, which includes: a planar waveguide, especially delimited by a front face and a rear face parallel to each other; an injection zone, comprising two input facets, each extending from a side face of the planar waveguide, configured to separate an initial light beam into two sub-beams each deflected in a respective direction when they enter the planar waveguide; and an extraction zone, including two output facets, configured to receive the two sub-beams, and to deflect the same when they exit the planar waveguide, the optical component being configured so that the two sub-beams can interfere with each other after emerging out of the planar waveguide.

A method includes receiving a representation of an N-mode interferometer and a representation of at least one imperfection associated with the N-mode interferometer at a processor, N being a positive integer value. The processor identifies multiple two-mode interferometers and multiple phases based on the representation of the N-mode interferometer and the representation of the at least one imperfection. The multiple two-mode interferometers and the multiple phases are configured to apply a unitary transformation to an input signal. The method also includes sending a signal to cause at least one of storage or display of a representation of the multiple two-mode interferometers and a representation of the multiple phases.