Efficient interferometer designs for optical coherence tomography (OCT) systems are presented. One example interferometer design includes two polarization dependent beamsplitters and a non-polarization dependent combiner. The first polarization dependent beamsplitter transmits light in a first polarization state to a sample arm of the OCT system and transmits light in a second polarization state different from the first polarization state to a reference arm of the system. The second polarization dependent beamsplitter transmits light returning from a sample to the non-polarization dependent combiner. The combiner combines light returned from the sample and the light that has passed through the reference arm, which is then detected at a detector. Another example interferometer design includes free space optics comprising a non-reciprocal beamsplitting element in a beam path from a light source to a sample. The non-reciprocal beamsplitting element is implemented using a combination of a polarization dependent beamsplitter and a polarization manipulator.

An imaging system can include of a plurality of pairs of lenslets and a respective plurality of two-dimensional arrays of photonic waveguides arranged in a respective plurality of photonic integrated circuits. Each waveguide can collect light in an airy-disk-size bin to cover a full field of view of the lenslet. Light from each pair of respective waveguides from each pair of lenslets can be demultiplexed into wavelength bins and combined with appropriate phase shifts to enable a measurement of the complex visibility. The complex visibilities from all of the measurements then can be processed to form an image.

Disclosed herein are optical integration technologies, designs, systems and methods directed toward Optical Coherence Tomography (OCT) and other interferometric optical sensor, ranging, and imaging systems wherein such systems, methods and structures employ tunable optical sources, coherent detection and other structures on a single or multichip monolithic integration. In contrast to contemporary, prior-art OCT systems and structures that employ simple, miniature optical bench technology using small optical components positioned on a substrate, systems and methods according to the present disclosure employ one or more photonic integrated circuits (PICs), use swept-source techniques, and employ a widely tunable optical source(s). In another embodiment the system uses an optical photonic phased array. The phase array can be a static phased array to eliminate or augment the lens that couples light to and from a sample of interest or can be static and use a spectrally dispersive antenna and a tunable source to perform angular sweeping. The phased array can be active in 1 or 2 dimensions so as to scan the light beam in angle. The phased array can also adjust focus. The phased array can implement an optical waveform that will extend depth of field focus for imaging. The phase array can also be a separate standalone element that is fed by one or more optical fibers. The phased array can be for scanning a biomedical specimen used in conjunction with a swept-source OCT system, can be used in a free-space coherent optical communication system for beam pointing or tracking, used in LIDAR applications, or many other beam control or beam steering applications.

An optical microphone assembly comprises a rigid substrate; an interferometric arrangement, a light source, at least one photo detector and an enclosure. The interferometric arrangement comprises a membrane and at least one optical element spaced from the membrane, wherein the at least one optical element comprises a surface of the substrate and/or is disposed on a surface of the substrate. The light source is arranged to provide light to the interferometric arrangement such that a first portion of the light propagates along a first optical path via the interferometric arrangement and a second portion of the light propagates along a second different optical path via the interferometric arrangement, thereby giving rise to an optical path difference between the first and second optical paths which depends on a distance between the membrane and the optical element. The photo detector(s) are arranged to detect at least part of an interference pattern generated by said first and second portions of light dependent on said optical path difference. The enclosure is arranged to form an acoustic cavity in fluid communication with one side of the membrane. The volume of the acoustic cavity is at least 3 mm multiplied by d.sup.2, where d is a diameter of the membrane.

This invention describes the structure and function of an integrated multi-sensing system. Integrated systems described herein may be configured to form a microphone, pressure sensor, gas sensor or accelerometer. The system uses Fabry-Perot Interferometer in conjunction with beam collimator, beam splitter, optical waveguide and a photodetector integrated. It also describes a configurable method for tuning the integrated system to specific resonance frequency using electrostatic actuators.

A photodetection device comprises: an image sensor that includes first pixels, second pixels, third pixels, and fourth pixels; an interference element that includes first incident regions and second incident regions; and an optical system that causes light in a first wavelength band to be incident on the first incident regions and causes light in a second wavelength band different from the first wavelength band to be incident on the second incident regions. The interference element causes first interference of part of the light in the first wavelength band incident on two first incident regions that are included in the first incident regions. The interference element also causes second interference of part of the light in the second wavelength band incident on two second incident regions.

A method and system described for sensing a displacement by receiving and propagating a laser light signal with an etched waveguide that is configured to enable an evanescent optical field above the waveguide surface. A movable perturber can be positioned so the perturber interacts with the evanescent optical field above the waveguide surface. An optical phase shift can be induced in the waveguide when the movable perturber is displaced in the evanescent optical field, and the optical phase shift can be measured with an optical readout circuit.

A wavelength tunable laser device includes a gain element positioned in an optical cavity that provides optical gain to an optical signal. A frequency shifter that generates a frequency shift as a function of time is positioned in the optical cavity. The optical cavity is configured so that a magnitude of the frequency shift as a function of time generated by the frequency shifter is substantially equal to a frequency separation of a cavity mode of the cavity such that an output of the cavity generates laser light having a wavelength that tunes as a function of time.

An optical module 1 includes: a mirror unit 2 including a base 21, a movable mirror 22, and a fixed mirror 16; a beam splitter unit 3 that is disposed on one side of the mirror unit 2 in a Z-axis direction; a light incident unit 4 that causes measurement light L0 to be incident to the beam splitter unit 3; a first light detector 6 that is disposed on the one side of the beam splitter unit 3 in the Z-axis direction, and detects interference light L1 of measurement light which is emitted from the beam splitter unit 3; a support 9 to which the mirror unit 2 is attached; a first support structure 11 that supports the beam splitter unit 3; and a second support structure 12 that is attached to the support 9 and supports the first light detector 6.

An OCT system for measuring a retina as part of an eye health monitoring and diagnosis system. The OCT system includes an OCT interferometer, where the interferometer comprises a light source or measurement beam and a scanner for moving the beam on the retina of a patient's eye, and a processor configured to execute instructions to cause the scanner to move the measurement beam on the retina in a scan pattern. The scan pattern is a continuous pattern that includes a plurality of lobes. The measurement beam may be caused to move on the retina by the motion of a mirror that intercepts and redirects the measurement beam. The mirror position may be altered by the application of a drive signal to one or more actuators that respond to the drive signal by rotating the mirror about an axis or axes.