A spectroscopy system includes a light source having an input light source, including semiconductor diodes generating an input beam with a wavelength shorter than 2.5 microns. Cladding-pumped fiber amplifiers receive the input beam and form an amplified optical beam having a spectral width. A nonlinear element broadens the spectral width of the amplified optical beam to 100 nm or more through a nonlinear effect forming an output beam that is pulsed. A filter is coupled to at least one of a lens and a mirror that receives the output beam and delivers the filtered output beam to a sample. A detection system includes detectors configured to receive the output beam reflected or transmitted from the sample. The detection system is configured to use a lock-in technique with the pulsed output beam and the spectroscopy system is adapted to detect chemicals in the sample.

A demultiplexing unit that is provided in an optical device and performs demultiplexing into a plurality of optical signals having wavelengths different from each other includes a plurality of optical filters that are coupled in multiple stages and in which a period of a peak wavelength of a transmission spectrum differs among different stages, a monitoring optical filter coupled to one of the plurality of optical filters, a monitoring photodetector coupled to the output side of the monitoring optical filter, and a plurality of wavelength adjustment units that are provided individually for the plurality of optical filters and the monitoring optical filter and cause wavelength shifts of an equal amount in a same direction.

A device. The device includes a substrate a substrate, a first optical waveguide disposed on the substrate and a second optical waveguide disposed on the substrate. The device further includes a coupling element disposed on the substrate, the coupling element configured to couple an optical signal in the first optical waveguide to the second optical waveguide, and couple an optical signal in the second optical waveguide to the first optical waveguide. A first reflective element is disposed at an end of the first optical waveguide configured to reflect optical signals in the first optical waveguide. A second reflective element disposed at an end of the second optical waveguide configured to reflect signals in the second optical waveguide.

An example embodiment may include an interferometer. The interferometer may include a multimode waveguide with an input waveguide optically coupled to a first side of the multimode waveguide, for feeding a light signal to the multimode waveguide. The interferometer may also include a first waveguide at one end optically coupled to a second side of the multimode waveguide, and at the other end terminated by a first waveguide mirror. The interferometer may also include a second waveguide at one end optically coupled to the second side of the multimode waveguide and at the other end terminated by a second waveguide mirror. The multimode waveguide may be adapted to distribute the light signal towards the first and second waveguide mirror via the first waveguide and via the second waveguide.

An optical comb filter, comprising an input/output collimator (50), an output collimator (60), a spectroscope (10), and first, second and third GT resonant cavities (20, 30, 40), wherein each GT resonant cavity comprises a transparent solid block coated with a membrane layer and a spacing part, a through hole is provided on the transparent solid block, and the transparent solid block and the spacing part form a hollow cavity; and rectangular orientation of an insertion loss curve is realized, and the bandwidth utilization rate is high.

A demultiplexing unit that is provided in an optical device and performs demultiplexing into a plurality of optical signals having wavelengths different from each other includes a plurality of optical filters that are coupled in multiple stages and in which a period of a peak wavelength of a transmission spectrum differs among different stages, a monitoring optical filter coupled to one of the plurality of optical filters, a monitoring photodetector coupled to the output side of the monitoring optical filter, and a plurality of wavelength adjustment units that are provided individually for the plurality of optical filters and the monitoring optical filter and cause wavelength shifts of an equal amount in a same direction.

A spectroscopy system includes a light source having an input light source, including semiconductor diodes generating an input beam with a wavelength shorter than 2.5 microns. Cladding-pumped fiber amplifiers receive the input beam and form an amplified optical beam having a spectral width. A nonlinear element broadens the spectral width of the amplified optical beam to 100 nm or more through a nonlinear effect forming an output beam that is pulsed. A filter is coupled to at least one of a lens and a mirror that receives the output beam and delivers the filtered output beam to a sample. A detection system includes detectors configured to receive the output beam reflected or transmitted from the sample. The detection system is configured to use a lock-in technique with the pulsed output beam and the spectroscopy system is adapted to detect chemicals in the sample.

A directly modulated semiconductor laser whose optical output can be modulated by varying the transmittance of an end reflector of the laser cavity. In an example embodiment, the end reflector can be implemented using a lightwave circuit in which optical waveguides are arranged to form an optical interferometer. At least one of the optical waveguides may include a waveguide section configured to modulate the phase of an optical beam passing therethrough in response to an electrical radio-frequency drive signal in a manner that causes the transmittance and reflectance of the end reflector to be modulated accordingly. Advantageously, relatively high (e.g., >10 GHz) phase and/or amplitude modulation speeds of the optical output can be achieved in this manner to circumvent the inherent modulation-speed limitations of the laser's gain medium.

An apparatus on a satellite includes a standard fixed-path Michelson interferometer. The Michelson interferometer includes an input, at least one first output detector, and at least one second output detector. The Michelson interferometer includes a plurality of respective fields of view and a corresponding plurality of scanning azimuthal angles relative to a satellite velocity vector. The plurality of respective fields of view corresponds to a plurality of tangent points with constant tangent point height arranged around an Earth horizon circle. The apparatus includes an attitude determination and control system on the satellite, or an actuator on the satellite. The apparatus includes an input mirror and/or input optics in optical communication with the input of the Michelson interferometer. The attitude determination and control system rotates the satellite or the actuator rotates the input mirror and/or the input optics, so as to sweep through the plurality of respective fields of view around the Earth horizon circle.

A super continuum light source includes an input light source having semiconductor diodes generating an input beam having a wavelength shorter than 2.5 microns. Optical amplifiers receive the input beam and form an amplified optical beam having a spectral width. The optical amplifiers may include a cladding-pumped fiber amplifier doped with rare-earth materials. A nonlinear element may include mid-infrared fibers to receive the amplified optical beam and to broaden the spectral width of the received amplified optical beam to 100 nm or more through a nonlinear effect forming an output beam, wherein the output beam is pulsed. At least a portion of the output beam is in a mid-infrared wavelength range between 2 microns and 5 microns and at least a portion of the one or more mid-infrared fibers comprises a ZBLAN fluoride fiber coupled to a chalcogenide fiber.