Abstract:
An improved optical system is disclosed for rapid, accurate spectral analysis of the reflectivity or transmissivity of samples. A concave holographic diffraction grating oscillated at high speed is utilized to provide a rapid scanning of monochromatic light through a spectrum of wavelengths. The grating is positively driven at very high speed. The rapid scan by the grating enables the reduction of noise error by averaging over a large number of cycles. It also reduces the measurement time and thus prevents sample heating by excessive exposure to light energy. A filter wheel having opaque segments is rotated in the optical path and is synchronous with the grating. The filter wheel is divided into two arcuate segments separated by the opaque segments arranged approximately 180 degrees apart. One arcuate segment of the wheel transmits only first order light. The other arcuate segment transmits only second order light. Separate photodetectors are employed during infrared analysis of samples for detecting first order and second order wavelength transmissions and an electronic decoder apparatus is utilized for switching between detectors.
Abstract:
The use of an optical fiber for providing a point source of radiation at the entrance of a spectrometer obviates the necessity for an entrance slit at the input end of the device. Improved optical imaging at decreased expense is achieved.
Abstract:
A spectroscopic unit and spectroscopic device according to the present invention are provided with a filter that is provided with a plurality of optical filter elements disposed in order from the entrance side to the exit side of light under measurement and has different transmission wavelengths corresponding to entrance positions along a first direction. A first optical filter element from among the plurality of optical filter elements is tilted with respect to a second optical filter element disposed adjacently to the first optical filter element as a result of the first optical filter element being rotated by a prescribed angle with a third direction that is perpendicular to both the first direction and s second direction from the entrance side to the exit side as the axis of rotation thereof or being rotated by a prescribed angle with the first direction as the axis of rotation thereof.
Abstract:
A portable spectroscopic device for acquiring single-frame spatial, spectral, and polarization information of an object. The device includes a modular dispersion element assembly that is coupled to a mobile computing device and disperses light into a plurality of different wavelengths. The mobile computing device includes a sensor and is configured to receive and analyze the plurality of wavelengths. The mobile computing device is also configured to perform automatic calibrations to determine the absolute wavelength axis and make stray-light corrections with minimal user intervention, thus making it amenable for untrained users not familiar with the state of the art. The mobile computing device is also configured to extend dynamic range.
Abstract:
A novel device, method and systems disclosed managing the thermal challenges of LIBS laser components and a spectrometer in a handheld structure as well the use of simplified light signal collection which includes a bare fiber optic to collect the emitted light in close proximity to (or in contact with) the test material. In one example embodiment of the handheld LIBS device, a burst pulse frequency is 4 kHz is used resulting in a time between pulses of about 250 μs which is a factor of 10 above that of other devices in the prior art. In a related embodiment, an active Q-switched laser module is used along with a compact spectrometer module using a transmission grating to improve LIBS measurement while substantially reducing the size of the handheld analyzer.
Abstract:
A liquid sample analyzer includes a liquid sample source, a flow cell, an optical device and a plurality of optical fibers. The flow cell is configured to receive a flow of a liquid sample from the liquid sample source. The plurality of optical fibers optically connect the flow cell to the optical device to transmit light between the flow cell and the optical device.
Abstract:
A liquid sample analyzer includes a liquid sample source, a flow cell, an optical device and a plurality of optical fibers. The flow cell is configured to receive a flow of a liquid sample from the liquid sample source. The plurality of optical fibers optically connect the flow cell to the optical device to transmit light between the flow cell and the optical device.
Abstract:
A fiber optic probe assembly is provided. The probe comprises a first optical system and a second optical system, a delivery light guide comprising one or more than one delivery optical fiber for transmitting excitation radiation from a radiation source disposed at a proximal end of the light guide to the first optical system. The first optical system comprising one or more than one first optical element for forming a substantially collimated illumination beam from the excitation radiation. An optically opaque tubular sleeve is fitted over the first optical system to optically isolate the first optical system and the delivery light guide from the second optical system. The second optical system comprising one or more than one second optical element for gathering optical radiation scattered from a sample and forming the optical radiation into a collection beam. A collection light guide comprising one or more than one collection optical fiber receives the collection beam and transmits the collection beam to an analyzer. The first and second optical systems are disposed within a housing so that an emission cone of the first optical system and an acceptance cone of the second optical system substantially overlap. A spectroscopic measurement system comprising the optic fiber probe is also provided.
Abstract:
A probe head for a diagnostic instrument, the probe head comprising; a transmission optical fiber, a plurality of collection optical fibers, and a lens to transmit light from the transmission optical fiber to a test site, wherein the ends of the collection optical fibers are bevelled.
Abstract:
The present disclosure provides for a system and method for analyzing a sample comprising at least one unknown material. A first location may be scanned to generate a SWIR hyperspectral image. The SWIR hyperspectral image may be generated using dual polarization techniques. The SWIR hyperspectral image may be analyzed to target a second location comprising the unknown material. This second location may be further analyzed using Raman spectroscopic techniques and a Raman data set may be generated. The Raman data set may be further analyzed to associate the unknown material with a know material.