Abstract:
A hyper-spectral imaging filter has serial stages along an optical signal path in a Solc filter configuration. Angularly distributed retarder elements of equal birefringence are stacked in each stage, with a polarizer between stages. The retarders can include tunable (such as abutted liquid crystals tuned in unison), fixed and/or combined tunable and fixed birefringences. Although the retardations are equal within each stage, distinctly different retardations are used for two or more different stages. This causes some stages to pass narrow bandpass peaks and other stages to have widely spaced bandpass peaks. The transmission functions of the serial stages are superimposed with selected preferably-tunable peaks coinciding. The resulting conjugate filter has a high finesse ratio, and good out of band rejection.
Abstract:
The disclosure generally relates to a method and apparatus for multi- wavelength imaging spectrometer. More specifically, in one embodiment, the disclosure relates to an optical filter for passing photons therethrough. Th e filter includes a first filter stage and a second filter stage. The first filter stage may include a first retarder element (450) and a first liquid crystal cell (455). The first element may include an input face and an outpu t face. One of the first element faces is not oriented substantially normal to the trajectory of photons passing through the filter.
Abstract:
A hyper-spectral imaging filter has serial stages (33, 35) along an optical signal path, each stage having angularly arranged retarder elements (45, 47) and one or more polarizers (42, 44). The retarders can include tunable (such as abutted liquid crystals tuned in unison), fixed and/or combined tunable and fixed birefringences, and can be arranged in Sole, Lyot, Evans or similar configurations. Each stage has a periodic transmission characteristic with periodic bandpass peaks (52) spaced by free spectral range bandpass gaps. Distinctly different retardations are employed in cascaded stages, causing some stages to pass narrow bandpass peaks and other stages to have widely spaced bandpass peaks (large free spectral range). The transmission functions of the serial stages are superimposed, providing a high finesse ratio and good out-of- band rejection. Preferably at least some stages have tunable liquid crystals for at least part of their retardation, and are controlled to selectively align respective bandpass eaks.
Abstract:
The disclosure relates to methods and apparatus for assessing occurrence of one or more hazardous agents in a sample by performing multipoint spectral analysis of the sample using a portable or hand-held device. Methods of employing Raman spectroscopy and other spectrophotometric methods are disclosed. Devices and systems suitable for performing such multipoint methods are also disclosed.
Abstract:
The disclosure generally relates to a method and apparatus for multi-wavelength imaging spectrometer. More specifically, in one embodiment, the disclosure relates to an optical filter for passing photons therethrough. The filter includes a first filter stage and a second filter stage. The first filter stage may include a first retarder element (450) and a first liquid crystal cell (455). The first element may include an input face and an output face. One of the first element faces is not oriented substantially normal to the trajectory of photons passing through the filter.
Abstract:
The disclosure generally relates to a method and apparatus for multi-wavelength imaging spectrometer. More specifically, in one embodiment, the disclosure relates to an optical filter for passing photons therethrough. The filter includes a first filter stage and a second filter stage. The first filter stage may include a first retarder element (450) and a first liquid crystal cell (455). The first element may include an input face and an output face. One of the first element faces is not oriented substantially normal to the trajectory of photons passing through the filter.
Abstract:
The disclosure relates to a portable system for obtaining a spatially accurate wavelength-resolved image of a sample having a first and a second spatial dimension that can be used for the detection of hazardous agents by irradiating a sample with light, forming an image of all or part of the sample using Raman shifted light from the sample, and analyzing the Raman shifted light for patterns characteristic of one or more hazardous agents.
Abstract:
The disclosure generally relates to a multimode imaging apparatus for simultaneously obtaining multiple wavelength-discriminative spectral images of a sample (100). In one embodiment, the apparatus includes an image selector (108) having a rotator assembly, the rotator assembly housing a first plurality of optical components, the image selector adapted to receive a illuminating photons having a first wavelength and direct the illuminating photons to the sample, the image selector (108) adapted to receive illuminating photons interacted with the sample and selectively direct said interacted photons to one of a plurality of detection sources; a microscope turret (102) housing a second plurality of components, the microscope turret (102) adapted to receive illuminating photons having a second wavelength and direct the photons to the sample; the microscopic turret (102) adapted to receive illuminating photons interacted with the sample and selectively direct said interacted photons to one of a plurality of detection sources; wherein substantially all of the interacted photons are selectively directed one of a plurality of detection sources to form multiple wavelength discriminative spectral images of the sample simultaneously.