Abstract:
A manufacturing method for a grating is disclosed for the angular dispersion of light impinging the grating. The grating comprises tapered structures and cavities. A cavity width and/or corrugation amplitude is varied for achieving a desired grating efficiency according to calculation. A method is disclosed for conveniently creating gratings with variable cavity width and/or corrugation amplitude. The method comprises the step of anisotropically etching a groove pattern into a grating master. Optionally a replica is produced that is complementary to the grating master. By variation of an etching resist pattern, the cavity width of the grating may be varied allowing the optimization towards different efficiency goals.
Abstract:
Various embodiments of apparatuses, systems and methods are described herein for a spectrometer comprising at least two dispersive elements configured to receive at least one input optical signal and generate two or more pluralities of spatially separated spectral components, at least a portion of the at least two dispersive elements being implemented on a first substrate; and a single detector array coupled to the at least two dispersive elements and configured to receive and measure two or more pluralities of narrowband optical signals derived from the two or more pluralities of spatially separated spectral components, respectively.
Abstract:
A device for detecting gas concentrations includes a movable coded filter. An optical element is positioned to receive gas filtered light and spectrally separate the gas filtered light. A photo detector is positioned to receive the spectrally separated light through slits in the moveable coded filter to provide an AC signal representative of a selected gas.
Abstract:
Wavenumber linear spectrometers are provided including an input configured to receive electromagnetic radiation from an external source; collimating optics configured to collimate the received electromagnetic radiation; a dispersive assembly including first and second diffractive gratings, wherein the first diffraction grating is configured in a first dispersive stage to receive the collimated electromagnetic radiation and wherein the dispersive assembly includes at least two dispersive stages configured to disperse the collimated input; and an imaging lens assembly configured to image the electromagnetic radiation dispersed by the at least two dispersive stages onto a linear detection array such that the variation in frequency spacing along the linear detection array is no greater than about 10%.
Abstract:
High resolution fast tunable optical filters are described such that each filter includes a tunable single-peak narrow-bandwidth (SPNB) filter and a tunable etalon in tandem with the tunable SPNB filter, where the bandwidth of the tunable SPNB filter is less than the free spectral range (FSR) of the tunable etalon.
Abstract:
A spectrometer includes a light source to project a light beam to a target object, a spectral element to disperse the light beam reflected by the target object and including a diffraction element to diffract the light beam, and a light receiving element to receive, at pixels, light beams with different spectral characteristics from each other dispersed by the spectral element, wherein the diffraction element and the light receiving element are integrally formed.
Abstract:
A compact wavelength dispersing device and a wavelength selective optical switch based on the wavelength dispersing device is described. The wavelength dispersing device has a folding mirror that folds the optical path at least three times. A focal length of a focusing coupler of the device is reduced and the NA is increased, while the increased optical aberrations are mitigated by using an optional coma-compensating wedge. A double-pass arrangement for a transmission diffraction grating allows further focal length and overall size reduction due to increased angular dispersion.
Abstract:
An spectrometer having a first lens, a perforated focal plane mask having a front surface and rear surface and a plurality of perforations, the first lens configured to focus incoming radiation onto a front surface of the focal plane mask, each of the perforations of the focal plane mask causing a radiation beam that is emitted from the rear surface of the focal plane mask, a dispersing element receiving the radiation beams and configured to disperse each of the radiation beams into dispersed radiation beams, a second lens, and a focal plane array, the second lens configured to focus the dispersed radiation beams onto the focal plane array.
Abstract:
Spectral device includes: diffraction element which disperses light for each wavelength; optical condensing system which condenses diffracted light of specific order generated by diffraction in the diffraction element; photo-detector arranged at position where the diffracted light of the specific order is condensed by the optical condensing system; first deflection device which inverts the direction of travel of second light as zeroth-order diffracted light generated by diffraction of first light which has entered the diffraction element as parallel luminous flux, and leads the second light into the diffraction element; and second deflection device which deflects the diffracted light of the specific order generated by diffraction of the second light which has entered the diffraction element in the same direction as the diffracted light of the specific order generated by the diffraction of the first light, and leads the deflected light into the optical condensing system.
Abstract:
A spectrometer includes a light source to project a light beam to a target object, a spectral element to disperse the light beam reflected by the target object and including a diffraction element to diffract the light beam, and a light receiving element to receive, at pixels, light beams with different spectral characteristics from each other dispersed by the spectral element, wherein the diffraction element and the light receiving element are integrally formed.