Abstract:
System and method for detecting and measuring chemical perturbations in a sample. The system and method are useful for non-invasive pH monitoring of blood or blood products sealed in storage bags.
Abstract:
An apparatus for detecting light emanating from chemical or biochemical reactions occurring in at least one reaction vessel of a plurality of reaction vessels is disclosed. Each reaction vessel has a receptacle portion having an emitting area from which light can emanate. A plurality of light waveguides are arranged to guide light from apertures in a masking element to a light dispersing device for dispersing the light from each waveguide into a dispersed spectrum. A light detecting device detects specific spectra in the dispersed spectra of light substantially simultaneously In one embodiment, the light waveguides have a diameter that tapers from a first end substantially similar in diameter to the area of the top of the reaction vessel to a second end that is substantially smaller in diameter.
Abstract:
A noninvasive analyzer apparatus and method of use thereof is described using a sample mapping phase to establish one or more analyzer/software parameters used in a subsequent individual and/or group specific data collection phase. For example, in the sample mapping phase distance between incident and collected light is varied as a function of time for collected noninvasive spectra. Spectra collected in the sample mapping phase are analyzed to determine a physiological property of the subject, such as dermal thickness, hydration, collagen density, epidermal thickness, and/or subcutaneous fat depth. Using the physiological property or measure thereof, the analyzer is optically reconfigured for the individual to yield subsequent spectra having enhanced features for noninvasive analyte property determination. Similarly, in the mapping and/or collection phase, the incident light is varied in time in terms of any of: sample probe position, incident light solid angle, incident light angle, depth of focus, energy, and/or intensity.
Abstract:
The disclosure relates to a method of detecting a change in a chemical composition by contacting a doped oxide material with a monitored stream, illuminating the doped oxide material with incident light, collecting exiting light, monitoring an optical signal based on a comparison of the incident light and the exiting light, and detecting a shift in the optical signal. The doped metal oxide has a carrier concentration of at least 1018/cm3, a bandgap of at least 2 eV, and an electronic conductivity of at least 101 S/cm, where parameters are specified at a temperature of 25° C. The optical response of the doped oxide materials results from the high carrier concentration of the doped metal oxide, and the resulting impact of changing gas atmospheres on that relatively high carrier concentration. These changes in effective carrier densities of conducting metal oxide nanoparticles are postulated to be responsible for the change in measured optical absorption associated with free carriers. Exemplary doped metal oxides include but are not limited to Al-doped ZnO, Sn-doped In2O3, Nb-doped TiO2, and F-doped SnO2.
Abstract:
An apparatus for detecting light emanating from chemical or biochemical reactions occurring in at least one reaction vessel of a plurality of reaction vessels is disclosed. Each reaction vessel has a receptacle portion having an emitting area from which light can emanate. A plurality of light waveguides are arranged to guide light from apertures in a masking element to a light dispersing device for dispersing the light from each waveguide into a dispersed spectrum. A light detecting device detects specific spectra in the dispersed spectra of light substantially simultaneously In one embodiment, the light waveguides have a diameter that tapers from a first end substantially similar in diameter to the area of the top of the reaction vessel to a second end that is substantially smaller in diameter.
Abstract:
The present invention pertains to a method and apparatus for total hemoglobin measurement. A modulated optical signal based on a digital code sequence is transmitted to human tissue. A temporal transfer characteristic is derived from the modulated optical signal. Total hemoglobin is determined based on the temporal transfer characteristic.
Abstract:
A multi-channel source assembly for downhole spectroscopy has individual sources that generate optical signals across a spectral range of wavelengths. A combining assembly optically combines the generated signals into a combined signal and a routing assembly that splits the combined signal into a reference channel and a measurement channel. Control circuitry electrically coupled to the sources modulates each of the sources at unique or independent frequencies during operation.
Abstract:
An analytical instrument may have multiple distinct channels. Such may include one or more illumination sources and sensors. Illumination may be delivered to specific locations of a specimen holder, and returned illumination may be delivered to specific locations of a sensor array. Illumination may first pass a specimen, and a mirror or reflector may then return the illumination past the specimen. Optical splitters may be employed to couple pairs of fiber optics proximate a specimen holder. Such channels may further include a plurality of illumination sources positioned on one side of a specimen holder and a plurality of sensors on the other side. The plurality of sensor may capture image of a specimen and a spectrophotometer may concurrently scan the specimen. A plurality of specimens may be imaged and scanned in a single pass of a plurality of passes. Spherical or ball lenses may be placed in an optical path of the illumination to achieve a desired illumination pattern.
Abstract:
System and method for detecting and measuring chemical perturbations in a sample. The system and method are useful for non-invasive pH monitoring of blood or blood products sealed in storage bags.
Abstract:
A measurement system for use with fluorescent chemosensors has multiple stimulus light sources each coupled to at least one sensor. Multiple sensors each receiving light from a different light source connect to each of one or more photodetectors. A processing device drives the light sources in a time-division multiplexed manner, and reads the photodetector at an appropriate time for each sensor. The processing device calibrates the sensor readings and provides them in a way that is identified to the associated sensor.