Abstract:
A flame detector includes a medium wavelength infrared bolometer having an array of pixel elements disposed within a housing. Optics supported by the housing and disposed with respect to the bolometer direct infrared radiation from a flame to the pixel elements of the array and direct radiation from a separate background object to the pixel elements of the array. Electronics are coupled to receive signals from the bolometer and programmed to track an intensity of radiation from the background object to monitor transmission of radiation through the optics.
Abstract:
The present disclosure includes sensing device embodiments. One sensing device includes a heater layer, a resistance detector layer, constructed and arranged to indicate a temperature value based upon a correlation to a detected resistance value, an electrode layer, and a sensing layer.
Abstract:
An illustrative cavity ring down gas sensor includes an optical cavity for receiving a gas to be detected and at least two electromagnetic radiation sources. The first electromagnetic radiation source may emit a first beam of light having a wavelength corresponding to an absorption wavelength of the gas to be detected, and the second electromagnetic radiation source may emit a second beam of light having a second wavelength that is off of an absorption wavelength of the gas to be detected. The first beam of light may detect a cavity ring down time decay, which is related to the concentration of the gas to be detected. The second beam of light may be used to detect a baseline cavity ring down time decay, which may be used to help increase the accuracy of the sensor by, for example, helping to compensate the concentration of the gas detected by the first beam of light for sensor variations caused by, for example, sensor age, temperature or pressure changes, and/or other conditions.
Abstract:
An approach for obtaining a transducer mirror structure made from silicon. The structure may have a center portion and a perimeter portion that have an attachment between them which is made flexible after certain etching between the two portions. The attachment may be a web of links or legs. A force applied to the center portion at one end of the structure may cause the center portion to move relative to the perimeter portion. A piezo electric transducer or actuator may be attached to apply the force. An oxide layer, a thin layer of silicon and a mirror may be formed on the other end of the structure. The web of links or legs between the center and the perimeter portions may be established with an RIE etch of gaps through the structure to the oxide layer and an undercutting of the gaps with a KOH etch.
Abstract:
A pixel having a reflector situated on a substrate. A temperature sensitive resistor may be situated over at least a portion of the reflector. An insulator may be situated on the resistor. The resistor and insulator may effectively be very thin films. A flat metal mesh or grid may be situated on the insulator. The grid, insulator and resistor may be supported by two or more posts at approximately one-fourth of a wavelength from the reflector. The wavelength may be that of the radiation to be sensed by the pixel. The thermal mass of the combination of the temperature sensitive resistor, insulator and grid may be less than several times the thermal mass of the grid. Since the grid may be so thin for low noise performance and high sensitivity, the grid can have a flatness assured to a desired extent with stiffeners attached to portions of it.
Abstract:
A cavity ring-down spectroscope includes a ring-down cavity. A trigger detector is optically coupled within the ring-down cavity to generate a signal to indicate a desired radiation level in the ring-down cavity. A controller is coupled to the trigger detector to control light provided to the ring-down cavity. A ring-down time may then be measured.
Abstract:
A metal oxide semiconductor (MOS) device includes a substrate, a lower sacrificial membrane adjacent to the substrate, an upper thin film structure adjacent to the lower membrane, and a MOS material deposited on the upper thin film structure.
Abstract:
The invention is a method and apparatus capable of detecting constituents of a gas at extremely low concentrations comprising providing a medium that is absorbent of at least a first particular gas under a first environmental condition and desorbent of the particular gas under a second environmental condition, exposing the medium to a sample gas for a first period of time under the first environmental condition, during a second period of time after the first period of time, exposing the medium to the second environmental condition to cause the medium to desorb gas into an optical cavity of a cavity ring down spectrometer and introducing electromagnetic radiation into the cavity, during a third period of time after the second period of time, ceasing introduction of the electromagnetic radiation into the cavity and detecting the decay of the electromagnetic radiation in the cavity, and analyzing the decay of the light in the cavity to obtain a spectral analysis of the sample gas.
Abstract:
A surface enhanced Raman scatter (SERS) analyte analyzer. The analyzer has floating surfaces for enhancement of the Raman scattered light from sample molecules. An injector may provide a spray of charged nanoparticles suspended in droplets of an evaporable solution into a chamber. When the solution quickly evaporates, droplets of nanoparticles are left without a supporting solution. These droplets or cloud of charged nanoparticles may then explode into a dispersion or aerosol. The charged nanoparticles may attract molecules of a sample for attachment to their surfaces. A laser light may impinge the attached molecules which may result in surface enhanced Raman scattered light received by a detector or a light spectrometer. Wavelength signatures may then be obtained from the spectrometer. The signatures may provide information about the molecules.
Abstract:
A multi-substrate package assembly having a first substrate, a second substrate and a package, each with a number of bond pads. The package includes a cavity for receiving either or both of the first and second substrates, with a number of bond pads positioned along at least part of the periphery of the cavity. The first substrate and the second substrate are preferably positioned in the cavity of the package, with selected bond pads of the first substrate and second substrate electrically connected to selected bond pads of the package. In some embodiments, the bond pads of the first substrate are only connected to bond pads on one or more sides of the cavity, and the bond pads of the second substrate are only connected to bond pads on one or more of the remaining sides of the cavity. The packaging assembly of the present invention can be used in many applications, including spectrally tunable optical detectors.