Abstract:
The invention provides an energy dispersion device, spectrograph and method that can be used to evaluate the composition of matter on site without the need for specialized training or expensive equipment. The energy dispersion device or spectrograph can be used with a digital camera or cell phone. A device of the invention includes a stack of single- or double-dispersion diffraction gratings that are rotated about their normal giving rise to a multiplicity of diffraction orders from which meaningful measurements and determinations can be made with respect to the qualitative or quantitative characteristics of matter.
Abstract:
A THz radiation detector comprising a vertical antenna separated from a suspended platform by an isolating thermal air gap for concentrating THz radiation energy into a smaller suspended MEMS platform upon which a thermal sensor element is located. THz photon energy is converted into electrical energy via a thermally isolated air gap between plates of a coupling capacitor that couples energy from the antenna to the thermal sensor. The capacitor plates used for capacitive coupling of the received signal realize an electro-static actuator whereby the application of a DC bias varies the coupling capacitor gap. The DC bias causes the actuator to pull the suspended platform close to the antenna to reduce the capacitive gap, increasing the coupling capacitance, to touch the antenna array thus quickly discharging the heat induced in the sensor platform or to perform advanced readout operations, such as amplitude modulation and correlated double sampling.
Abstract:
An adjustable holder (1) for a concave holographic grating (2) for enabling the correct positioning of the grating vis-à-vis a light entrance port (15) and a light exit port (20), characterized in, that it comprises a grating hinge (10) fixed to said grating, said grating hinge (10) enabling rotational adjustment of the grating position with respect to said holder (1), the center point of the rotational adjustment being located at the vertex of said grating (2).
Abstract:
A spectrophotometer includes a fixed substrate having a fixed reflecting film, a movable substrate having a movable reflecting film, a tunable interference filter having a static actuator changing the gap distance of an inter-reflecting film gap between the fixed reflecting film and the movable reflecting film, a detecting section detecting the light intensity of a light extracted by the tunable interference filter, a voltage setting section and a voltage controlling section that apply a continuously-varying analog voltage to the static actuator, a voltage monitoring section monitoring the voltage applied to the static actuator, and a light intensity obtaining section obtaining the light intensity detected by the detecting section when the voltage monitored by the voltage monitoring section becomes a predetermined voltage to be measured.
Abstract:
A method and apparatus is disclosed for resolving absorption spectra such as ultraviolet or visible spectra having individual peaks attributable to more than one component in a sample mixture. The invention exploits the observation that the peak wavelength varies according to the component concentrations, providing the basis for an initial estimate of these. A curve fitting exercise is performed for a range of possible concentrations encompassing the initial estimates so that the a theoretical spectrum having the closest match to that observed provides for a refined estimate of component concentrations.
Abstract:
A spectrometer cell can include a spacer, at least one end cap, and at least one mirror with a reflective surface. The end cap can be positioned proximate to a first contact end of the spacer such that the end cap and spacer at least partially enclose an internal volume of the spectrometer cell. The mirror can be secured in place by a mechanical attachment that includes attachment materials that are chemically inert to at least one reactive gas compound. The mechanical attachment can hold an optical axis of the reflective surface in a fixed orientation relative to other components of the spectrometer cell and or a spectrometer device that comprises the spectrometer cell. The mirror can optionally be constructed of a material such as stainless steel, ceramic, or the like. Related methods, articles of manufacture, systems, and the like are described.
Abstract:
A terahertz time-domain spectroscopic ellipsometry system includes a sample stage, a terahertz emitter configured to provide pulses of terahertz radiation with preselected polarization components to illuminate a sample on the sample stage along an incident direction, and a coherent terahertz detection system arranged to coherently detect pulses of terahertz radiation from the terahertz emitter along an emerging direction after at least one of reflecting from or passing through the sample. The sample stage is rotatable to vary a relative angle between the incident direction and the emerging direction, and the coherent terahertz detection system substantially maintains alignment for amplitude and polarization detection as the relative angle is varied.
Abstract:
The present invention relates to a trace gas detection system. At least one embodiment includes a frequency spectrum comprising a 1st comb and an enhancement cavity characterized by having a 2nd comb of spectral resonances. The enhancement cavity contains a sample gas for spectroscopic measurement. A dither mechanism is configured to modulate the relative spectral position between the combs at a dither frequency, fd. The dither mechanism, in conjunction with a feedback mechanism, stabilizes the location of said 1st comb lines with respect to the resonances of said 2nd comb over a time scale much greater than a dither period, Td=1/fd. A time-averaged output from the enhancement cavity is provided to a spectroscopic measurement tool, for example a Fourier transform spectrometer. The system is capable of detecting volatile organic compounds, endogenous compounds, and may be configured for cancer detection.
Abstract:
A method of non-destructively determining the condition of a material, said method including providing an elongated probe containing a plurality of optical fibers, said elongated probe coupled to an infrared spectrometer, said tip of said elongated probe positioned near said material, said elongated probe including said tip having a width of less than about 2.0 mm; and, making an infrared spectroscopy measurement of said material by providing infrared light from said infrared spectrometer through at least one of said plurality of optical fibers and collecting at least a portion of said infrared light reflected from a material juxtaposed near said tip through at least another of said plurality of optical fibers to provide said reflected light to said infrared spectrometer.
Abstract:
Apparatus and methods for the extracorporeal treatment of blood are described. The apparatus includes a dialyzer which is separated into a first and second chamber by a semipermeable membrane, wherein the first chamber is disposed in a dialysis fluid path and the second chamber can be connected to the blood circulation of a patient by way of a blood inflow conduit and a blood outflow conduit, a feed for fresh dialysis fluid, a discharge for spent dialysis fluid, a measuring device disposed within the discharge for determining the absorption of the spent dialysis fluid flowing through the discharge, wherein the measuring device has at least one radiation source for substantially monochromatic electromagnetic radiation, and a detector system for detecting the intensity of the electromagnetic radiation, wherein means are provided to compensate for changes that occur in the intensity of the electromagnetic radiation of the radiation source and/or the sensitivity of the detector system.