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

A reconfigurable optical add/drop multiplexer includes N input ports, N output ports, M add ports and M drop ports. Each of the N input ports and each of the M add ports is respectively connected to one first polarizer. Each of the N output ports and each of the M drop ports is respectively connected to one second polarizer. A first end of the first polarizer is connected to a second end of the first polarizer, forming a loop including the first polarizer. A first end of the second polarizer is connected to a second end of the second polarizer, forming a loop including the second polarizer. An annular waveguide array is between a loop L.sub.Ii and a loop L.sub.Oj. A first polarizer included in the loop L.sub.Ii is connected to an i.sup.th input port. A second polarizer included in the loop L.sub.Oj is connected to a j.sup.th output port.

The present invention relates to a Bell state measurement apparatus capable of increasing a probability in which a determination that a Bell state measurement fails by using an optical fiber.

Improvements to gratings for use in waveguides and methods of producing them are described herein. Deep surface relief gratings (SRGs) may offer many advantages over conventional SRGs and Bragg gratings, an important one being a higher S-diffraction efficiency. In one embodiment, deep SRGs can be implemented as polymer surface relief gratings or evacuated Bragg gratings (EBGs). EBGs can be formed by first recording a holographic polymer dispersed liquid crystal (HPDLC) grating. Removing the liquid crystal from the cured grating provides a polymer surface relief grating. Polymer surface relief gratings have many applications including for use in waveguide-based displays.

An optical-fiber measurement system includes an optical system that generates light and a spatial optical switch that is coupled to the optical system that processes the light generated by the optical system and generates light at a plurality of spatially distributed optical ports. A respective one of a plurality of optical cores at a first end of a multicore optical fiber is positioned to receive light from a respective one of the plurality of spatially distributed optical ports, where the light generated at the plurality of spatially distributed optical ports propagates through the multicore optical fiber. Distal optics is positioned adjacent to a second end of the multicore optical fiber and is positioned to collect light from a sample of interest so that the collected light from the sample of interest is coupled to the plurality of optical cores in the multicore optical fiber.

A method includes multiplexing signal light of first polarization and excitation light, and multiplexing signal light of second polarization, which is perpendicular to the first polarization, and the excitation light, modulating the signal light of the first polarization before the wavelength conversion, and reducing a modulation component in signal light after wavelength conversion, modulating the signal light of the second polarization before the wavelength conversion, and reducing the modulation component in the signal light after the wavelength conversion, and multiplexing the signal light of the first polarization after the wavelength conversion and the signal light of the second polarization after the wavelength conversion.

An optical-fiber atomic light-filtering apparatus comprising an optical-fiber coupling focusing collimating mirror, a first polarizing optical fiber, a first permanent magnetic ring, a pure iron frame shaped like the Chinese character , a heat preservation box, a first capillary atomic cell, an armored twisted-pair heating wire, a second permanent magnetic ring, a second polarizing optical fiber, a thermostat, a cable, a third permanent magnetic ring, a temperature sensor, a second capillary atomic cell, a fourth permanent magnetic ring, a third polarizing optical fiber and a photoelectric detector. The two pairs of permanent magnetic rings are matched with the pure iron frame shaped like the Chinese character to provide magnetic fields for the two capillary atomic cells working in the same temperature environment; a polarizing plane changes after interaction between a weak signal light and atoms.

A densely-spaced wavelength division multiplexing (DWDM) transceiver utilizes a comb laser source to provide a multi-channel system capable of supporting at least twenty separate channels. The optical transmitter portion of the transceiver utilizes a double-pass (e.g., reflective) modulator configuration. The double-pass arrangement allows for a single grating (or other suitable dispersive element) to be used as a demultiplexer in combination with the comb laser source to separate the input optical beams into individual wavelength components, as well as a multiplexer for combining the plurality of separate modulated optical signals into a single, multi-channel DWDM optical output signal. The optical receiver portion of the transceiver includes a grating element to direct the multi-channel received optical signal into separate, wavelength-based channels, with the signal propagating along each channel directed into a separate photodiode.

A reinforced multi-body optical device that in one embodiment includes a multi-body optical device having a thickness that is less than or equal to about 1.0 millimeter and a supporting plate bonded without epoxy to the multi-body optical device. In an embodiment the supporting plate has a coefficient of thermal expansion (CTE) that is within about 0.5 parts per million of the CTE of the multi-body optical device.

In the examples provided herein, a system includes a loop waveguide; and a grating coupler formed on the loop waveguide to couple light impinging on the grating coupler having a first polarization into the loop waveguide in a first direction, and to couple light having a second polarization, orthogonal to the first polarization, into the loop waveguide in a second direction. The system also includes a ring resonator positioned near the loop waveguide tuned to have a resonant wavelength at a first wavelength to couple light at the first wavelength out of the loop waveguide into the ring resonator. An output waveguide positioned near the ring resonator couples light out of the ring resonator into the output waveguide; and a photodetector detects light propagating out of a first end and a second end of the output waveguide.