Abstract:
A method of generating a design pattern for a spatial radiation modulator to encode two or more selected spectral components in one or more spectral ranges for the chemometric analysis of a group of analytes. The method includes obtaining a corresponding spectrum for each of the analytes, defining a set of initial spectral windows, constructing a chemometric matrix to relate concentrations of the analytes to intensities of the spectral components, deriving optimized spectral windows, and translating the center wavelength and the bandwidth of each of the optimized spectral windows into a corresponding optimized annular region on the modulator.
Abstract:
Encoded spatio-spectral information processing is performed using a system having a radiation source, wavelength dispersion device and two-dimensional switching array, such as digital micro-mirror array (DMA). In one aspect, spectral components from a sample are dispersed in space and modulated separately by the switching array, each element of which may operate according to a predetermined encoding pattern. The encoded spectral components can then be detected and analyzed. In a different aspect, the switching array can be used to provide a controllable radiation source for illuminating a sample with radiation patterns that have predetermined characteristics and separately encoded components. Various applications are disclosed.
Abstract:
In one embodiment, the disclosure relates to a method including: collecting photons from the sample having a plurality of regions to form a sample optical data set; selectively transmitting a first portion of the optical data set through a first of a plurality of apertures of an electro-optical shutter, each of the plurality of apertures optically communicating a portion of the optical data set; geometrically conforming the first portion of the optical data set for communication with a spectrometer opening; processing the conformed first portion of the optical data set at the spectrometer to obtain a spectrum for a first of the plurality of sample regions.
Abstract:
A spatial filter for an optical system, such as an optical spectrometer, collects and spatially filters light using a fiber bundle having a plurality of fibers disposed therein. At an input end of the fiber bundle, the fibers are typically packed tightly together to optimize the collection efficiency. At an output end, the fibers are spread out from the fiber bundle and arranged within a two-dimensional output area according to a two-dimensional pattern corresponding to a coded aperture function. As a result, the two-dimensional pattern of the output end spatially filters the light collected by the input end. Corresponding methods are also described.
Abstract:
A method and apparatus are provided for determining a property of a fluid downhole by using a tunable optical grating to collect a fluid's spectrum over a wavelength region of interest. A property of the fluid is estimated from spectra that are obtained from light that has interacted with the fluid and then been reflected off of the tunable optical grating onto a photodetector.
Abstract:
A prescription verification system includes a database that contains a plurality of spectral signatures corresponding to identified pharmaceuticals. A multimodal multiplex sampling (MMS) spectrometer obtains a spectra of a pharmaceutical to be identified and verified. The pharmaceutical can be inside or out of a vial. The prescription verification system includes algorithms for matching spectra of pharmaceuticals to be verified obtaining using the MMS spectrometer to spectral signatures contained in the database corresponding to identified pharmaceuticals. The prescription verification system further includes algorithms for identifying such pharmaceuticals to be verified.
Abstract:
Method and apparatus for analyzing radiation using analyzers and encoders employing the spatial modulation of radiation dispersed by wavelength or imaged along a line.
Abstract:
The invention relates to a Hadamard spectrometer which enables the detection of a range of polyatomic gases or liquids for example using infrared absorption. The aim of the invention is to produce a spectrometer of this type which provides higher resolution, improved wavelength precision and an improved signal-to-noise ratio using conventional detector lines and which allows a small and compact design. To this end, a detector line (30) with a set interval (a) between the individual detector areas (31) is used for a detector unit (3), and a linear assembly (10) is also used for a light-emitting respective reflective assembly (1). The linear assembly includes (n) adjoining identical light sources (11, 12, 13, 14), n always remaining ≧3, which can be activated individually according to the Hadamard Principle. The individual light sources (11, 12, 13, 14) are positioned at an interval (b) from each other in such a way that b is an integral multiple of a plus or minus 1/n when they are projected onto the detector line.
Abstract:
A multi-slit type spectrometer includes a light diffracter which diffracts an incident light according to wavelengths; an optical shutter array member including a plurality of optical shutter elements arranged in correspondence with wavelength bands diffracted by the light diffracter, operable to transmit an incident ray according to an applied voltage, and made of PLZT. A zone of a given number of adjacent optical shutter elements is applied with a voltage corresponding to the wavelength bands of the rays incident upon the zone of adjacent optical shutter elements at a specified timing so that the rays respectively pass through or are reflected at the optical shutter elements. A signal processor receives the ray which has passed through or has been reflected at each optical shutter element and outputs an electrical signal according to the intensity of the received ray. A calculator calculates the intensity of the incident ray for each wavelength band in accordance with the electrical signal output from the signal processor and the specified applying timing.
Abstract:
A spectrophotometer includes an array of light emitting diodes configured for activation in successive Hadamard encodement patterns, a diffraction grating, an optical slit, a detector and electronic controls including a computer. In operation, the diffraction grating disperses and collimates radiation from the array and directs selected spectral components through the slit onto the detector whereupon the computer performs a Hadamard analysis on the detector signals.