Abstract:
An apparatus for spectroscopic Doppler imaging comprises collection and focusing optics, a field splitter configured to form a composite image from multiple fields of view, and a Fabry-Perot etalon configured to spatially modulate the incoming light in order to analyze the spectral content of the light from spatially resolved regions of a scene. Methods for Doppler imaging of a scene comprise split-field imagery and scene scanning techniques to create a spatially resolved spectral profile spectra of a scene, useful for measuring and profiling wind vectors and temperatures within the scene.
Abstract:
A spectrometer with increased optical throughput and/or spectral resolution includes a plurality of interferometers coupled in parallel. An optical splitter divides a source light beam into a plurality of input beams and directs each of the input beams to a respective one of the plurality of interferometers. One or more detectors are optically coupled to receive a respective output from each of the plurality of interferometers and is configured to detect an interferogram produced as a result of the outputs.
Abstract:
A multi-channel infrared spectrometer for detecting an infrared spectrum of light received from an object. The spectrometer comprises a wavelength converter system comprising a nonlinear material and having an input side and an output side. The wavelength converter system comprises at least a first up-conversion channel and a second up-conversion channel, and is arranged such that light traversing the wavelength converter system at different angles in the nonlinear material is imaged into different positions in an image plane. The first up-conversion channel is configurable for phase-matching infrared light in a first input wavelength range incident on the first side and light in a first output wavelength range output on the second side, and correspondingly, the second up-conversion channel is configurable for phase-matching infrared light in a second input wavelength range incident on the first side into light in a second output wavelength range output on the second side. The spectrometer further comprises a demultiplexer configured for demultiplexing light in the first up-conversion channel and light in the second up-conversion channel. The demultiplexer is located on the first side or the second side of the wavelength converter system. Finally, the spectrometer comprises a spatially resolved detector arranged in the image plane to detect light in the first output wavelength range and second output wavelength range output of the wavelength converter system.
Abstract:
An optical module includes a circuit substrate that has a concave portion and a flat surface, an optical sensor that is disposed inside a space, and an optical filter device that has a base which accommodates a variable wavelength interference filter and has a light-through hole through which light emitted from the variable wavelength interference filter passes and a first glass member which is disposed in the light-through hole. The first glass member is positioned inside the space. The base is bonded to the flat surface. The distance between the first glass member and the optical sensor is set to a distance at which light emitted from the variable wavelength interference filter does not interfere between the first glass member and the optical sensor.
Abstract:
An optical filter includes: a lower substrate; a lower mirror provided to the lower substrate; a lower electrode provided to the lower substrate; an upper substrate disposed so as to be opposed to the lower electrode; an upper mirror provided to the upper substrate, and opposed to the lower mirror; and an upper electrode provided to the upper substrate, and opposed to the lower electrode, wherein the upper substrate has a groove surrounding the upper mirror in a plan view, the groove includes a first side surface section, a second side surface section, a bottom surface section, a first end section located between the first side surface section and the bottom surface section, and a second end section located between the second side surface section and the bottom surface section, in a cross-sectional view, and the first end section and the second end section each have a curved surface.
Abstract:
A spectroscopy system comprising at least two laser modules, each of the laser modules including a laser cavity, a quantum cascade gain chip for amplifying light within the laser cavity, and a tuning element for controlling a wavelength of light generated by the modules. Combining optics are used to combine the light generated by the at least two laser modules into a single beam and a sample detector detects the single beam returning from a sample.
Abstract:
An optical device includes: a diffraction grating; a depolarization plate containing a birefringent material to eliminate polarization dependency of the diffraction grating; and an optical corrector configured to optically correct diffraction angle deviation of diffracted light due to diffraction at the diffraction grating. The optical corrector may be configured to bend back the diffracted light diffracted by the diffraction grating to re-emit the light to the diffraction grating.
Abstract:
A printing apparatus includes: a discharging unit configured to discharge liquid onto a medium: a color measuring unit configured to measure a color of the medium on which the liquid has been discharged; a carriage on which the discharging unit and the color measuring unit are mounted; and a relative transporting unit configured to transport the medium and the carriage with respect to each other. The color measuring unit includes a variable wavelength interference filter configured to change a gap between reflecting films on substrates that face each other with the gap therebetween and shock-absorbing members are provided between the carriage and the color measuring unit.
Abstract:
An imaging system color image acquisition including: an image sensor; a tunable spectral filter arranged in an optical path of light propagation towards the image sensor; and a controller connected to the image sensor and to the tunable spectral filter. The controller is configured and operable for generating a colored image by sequentially operating the tunable spectral filter for sequentially filtering light passing towards the image sensor with three or more different spectral filtering curves during three or more corresponding integration time durations. The tunable spectral filter is configured, as an etalon and includes a pair of reflective surfaces. At least one of the reflective surfaces includes a layer of high refractive index of at least n=2.3 or even higher than 3, or a layer of low refractive index, smaller than n=1. The configuration of the etalon provide wide transmission peaks of the spectral curves with full-width-half maximum (FWHM) in the range of about 50 to 80 nm, free spectral range (FSR) of at least 300 nm, and thickness of the etalon in the order to 1 mm or even less.
Abstract:
A spectroscopic method using either tunable or preset non-tunable thin-layered devices or a combination of both to modulate compressed-sensing-compliant, spectral modulations and to use intensity measurements of each respective spectral modulation to numerically reconstruct an estimated spectral distribution of the spectral signal such that the estimated spectral distribution is characterized by a totality of spectral bands exceeding the number of spectral modulations by about one half an order-of-magnitude or more.