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:
The present invention discloses apparatuses and methods for non-invasive determination of attributes of human tissue by quantitative infrared spectroscopy. The embodiments of the present invention include subsystems optimized to contend with the complexities of the tissue measurements. The subsystems can include an illumination/modulation subsystem, a tissue sampling subsystem, a calibration maintenance subsystem, a data acquisition subsystem, and a computing subsystem. Embodiments of the present invention provide analyte property determination and identity determination or verification from the same spectroscopic information, making unauthorized use or misleading results less likely that in systems that include separate analyte and identity determinations. The invention can be used to prevent operation of automobiles or other equipment unless the operator has an acceptable alcohol concentration, and to limit operation of automobiles or other equipment to authorized individuals who are not intoxicated or drug-impaired.
Abstract:
A spatial Fourier transform spectrometer is disclosed. The Fourier transform spectrometer includes a Fabry-Perot interferometer with first and second optical surfaces. The gap between the first and second optical surfaces spatially varies in a direction that is orthogonal to the optical axis of the Fourier transform spectrometer. The Fabry-Perot interferometer creates an interference pattern from input light. An image of the interference pattern is captured by a detector, which is communicatively coupled to a processor. The processor is configured to process the interference pattern image to determine information about the spectral content of the input light.
Abstract:
Methods and systems for real-time monitoring of optical signals from arrays of signal sources, and particularly optical signal sources that have spectrally different signal components. Systems include signal source arrays in optical communication with optical trains that direct excitation radiation to and emitted signals from such arrays and image the signals onto detector arrays, from which such signals may be subjected to additional processing.
Abstract:
An apparatus includes an optical source providing an optical beam; a splitter configured to split the optical beam into a sample beam and a reference beam; a sample path containing a sample material to be analyzed, the sample beam being directed through the sample path so as to interact with the sample material; a reference path containing a reference material, the reference beam being directed through the reference path so as to interact with the reference material; a disperser configured to receive the sample beam after it exits the sample path and to receive the reference beam after it exits the reference path, the disperser outputting a dispersed sample beam and a dispersed reference beam; and a photodetector disposed to receive the dispersed sample beam and the dispersed reference beam and outputting electrical signals comprised of data indicative of a spectra of the sample beam after it exits the sample path and a spectra of the reference beam after it exits the reference path. In one embodiment the apparatus further includes a data processor connected with a memory storing a software program configured to process the data to detect a presence of at least one type of molecular species that includes the sample material; and a transmitter configured to transmit the processed data to a receiver. In another embodiment the apparatus includes a transmitter configured to transmit the data to a remote receiver for processing.
Abstract:
A spectrometric measurement apparatus includes a light radiation unit for radiating light onto a medium; a hole array including openings arranged one-dimensionally for transmitting diffusion light from the medium; an imaging optical system configured to focus an image from the hole array; a diffraction element configured to diffract the light for focusing the image; and a light receiving unit including pixels arranged one-dimensionally configured to receive the light that has been dispersed by the diffraction element and spectrometric sensors each corresponding to a predetermined number of the pixels. The light transmitted through each of the openings of the hole array is dispersed by the diffraction element, and then the light enters the pixels so that spectral properties of the diffusion light are acquired. The structure of the diffraction element includes variations that are formed in accordance with the height of the image that is focused by the imaging optical system.
Abstract:
An illumination subsystem configured to provide illumination for a measurement system includes first and second light sources configured to generate light for measurements in different wavelength regimes. The illumination subsystem also includes a TIR prism configured to be moved into and out of an optical path from the first and second light sources to the measurement system. If the TIR prism is positioned out of the optical path, light from only the first light source is directed along the optical path. If the TIR prism is positioned in the optical path, light from only the second light source is directed along the optical path. Various measurement systems are also provided. One measurement system includes an optical subsystem configured to perform measurements of a specimen using light in different wavelength regimes directed along a common optical path. The different wavelength regimes include vacuum ultraviolet, ultraviolet, visible, and near infrared wavelength regimes.
Abstract:
Hyperspectral imaging system and methods that may be used for imaging objects in three-dimensions are disclosed. A cylindrical lens array and/or a slit array may be used to re-image and divide a field of view into multiple channels. The multiple channels are dispersed into multiple spectral signatures and observed on a two-dimensional focal plane array in real time. The entire hyperspectral data cube is collected simultaneously.
Abstract:
Computer program products comprising tangible computer-readable media having instructions that are executable by a computer to generate a customized spectral profile, which can be used to generate a corresponding filter. The instructions can comprise: generating a trial source spectrum; determining an uncorrected lamp source spectrum; calculating one or more optical indices using the trial source spectrum or the uncorrected lamp source spectrum; and optimizing one or more of the optical indices by varying the trial source spectrum to generate the customized spectral profile.
Abstract:
The invention relates to angle-limiting optical reflectors and optical dispersive devices such as optical spectrum analyzers using the same. The reflector has two reflective surfaces arranged in a two-dimensional corner reflector configuration for reflecting incident light back with a shift, and includes two prisms having a gap therebetween that is tilted to reflect unwanted light and transmit wanted light. A two-pass optical spectrum analyzer utilizes the reflector to block unwanted multi-pass modes that may otherwise exist and degrade the wavelength selectivity of the device.