Disclosed is an optical sensor, including an external cavity laser configured to output sensing light and reference light; and a photodetector configured to detect a beating signal by an interference of the sensing light and the reference light output from the external cavity laser, in which the external cavity laser includes a reflecting filter including a sensing grating, to which a sensing object is attachable, and a reference grating, which is disposed on the same plane as that of the sensing grating, and outputs sensing light reflected from the sensing grating and reference light reflected from the reference grating. Accordingly, the optical sensor does not require a high-resolution spectroscope and has improved resolution and sensitivity.

Described herein are optical sensing devices for photonic integrated circuits (PICs). A PIC may comprise a plurality of waveguides formed in a silicon on insulator (SOI) substrate, and a plurality of heterogeneous lasers, each laser formed from a silicon material of the SOI substrate and to emit an output wavelength comprising an infrared wavelength. Each of these lasers may comprise a resonant cavity included in one of the plurality of waveguides, and a gain material comprising a non-silicon material and adiabatically coupled to the respective waveguide. A light directing element may direct outputs of the plurality of heterogeneous lasers from the PIC towards an object, and one or more detectors may detect light from the plurality of heterogeneous lasers reflected from or transmitted through the object.

Provided is an optical filter including a cladding layer, a plurality of metal patterns configured to form a periodic lattice structure on the cladding layer; and an optical waveguide layer on the plurality of metal patterns. Light travels from the optical waveguide layer to the cladding layer. Provided is an optical device using the optical filter.

A monitoring system for a power grid includes one or more power transformer monitors. Each power transformer monitor includes a plurality of optical sensors disposed on one or more optical fibers that sense parameters of the power transformer. Each optical sensor is configured to sense a power transformer parameter that is different from a power transformer parameter sensed by at least one other sensor of the plurality of optical sensors. An optical coupler spatially disperses optical signals from the optical sensors according to wavelength. A detector unit converts optical signals of the optical sensors to electrical signals representative of the sensed power transformer parameters.

Optical polarization-based devices and techniques are provided to enable low cost construction and easy signal processing to measure the light frequency via measurements of signals associated with a delay between the two orthogonal polarizations after passing through a DGD element and the retardation value of the DGD element without directly measuring the optical frequency. The optical detection may be designed in various configurations. In particular, for example, the optical detection may split the optical output of the DGD into two optical beams with two different optical detectors so that the final frequency information can be deducted into a pair of sine and cosine functions, such as a pair of sine and cosine functions of measured optical signal levels and the retardation value of the DGD element.

A remote sensing system for time-of-flight measurements may comprise an array of laser diodes with Bragg reflectors operating in the near-infrared wavelength range synchronized to a detection system comprising lenses, spectral filters and a photodiode array coupled to a processor. The time-of-flight depth information may be combined with various camera imaging systems. The camera system may comprise a lens system, prism and a sensor. In another embodiment, the data from two cameras may be combined with the time-of-flight depth information. Yet another embodiment comprises an imaging system with another array of laser diodes followed by a beam splitter and a detection system. The remote sensing system may be coupled to a smart phone, tablet or wearable device, and the combined data may provide three-dimensional information about at least some part of an object. Also, artificial intelligence may be used in the processing to make decisions regarding the depth and images.

A Fabry-Perot cavity-based spectral notch filter is disclosed, where the filter is operative for providing an output optical signal whose spectral content is spatially dispersed along at least one direction, while also controlling the spectral position and spectral range of the output light. In some embodiments, the spectral filter is integrated with a detector arrays to realize a compact, high-resolution spectrometer that can rapidly acquire the absorption spectrum of a sample with high sensitivity.

Described herein are optical sensing devices for photonic integrated circuits (PICs). A PIC may comprise a plurality of waveguides formed in a silicon on insulator (SOI) substrate, and a plurality of heterogeneous lasers, each laser formed from a silicon material of the SOI substrate and to emit an output wavelength comprising an infrared wavelength. Each of these lasers may comprise a resonant cavity included in one of the plurality of waveguides, and a gain material comprising a non-silicon material and adiabatically coupled to the respective waveguide. A light directing element may direct outputs of the plurality of heterogeneous lasers from the PIC towards an object, and one or more detectors may detect light from the plurality of heterogeneous lasers reflected from or transmitted through the object.

A probe can be provided having a grating adapted for color spectrally encoded imaging. The probe can include a waveguide configuration, a light focusing configuration, and a grating configuration that can have a first grating pattern and a second grating pattern. The waveguide configuration can be configured and/or structured to cause to propagate a light having a first wavelength and a light having a second wavelength to propagate from the waveguide component, and the light focusing and waveguide configurations can provide the light to be incident on the grating configuration. The grating configuration can be configured and arranged such that the light having the first wavelength is diffracted by the first grating pattern to substantially the same location as the light having the second wavelength is diffracted by the second grating pattern.

A fiber optic switching network includes a comb laser source that provides laser light at a plurality of wavelengths on a single optical fiber. Light from the comb laser source is directed into different optical fibers by a demultiplexer such as an arrayed waveguide grating (AWG) or cyclic AWG. Light from the demultiplexer is modulated with one or more demodulators and re-combined with a multiplexer into a single optical fiber for transmission to a destination.