摘要:
An electrical circuit incorporated in a receiver circuit of an ultrasonic pulse-echo thickness and/or velocity measuring apparatus causes the entrant surface and rear wall responsive video signals to be of equal magnitude and in phase with each other. The provision of echo responsive video signals having equal amplitude and phase results in a measuring apparatus exhibiting improved accuracy while requiring fewer and less expensive circuit components.
摘要:
A biochemical assay device optically scans individual biological sample containing wells in an assay plate. The device includes an imaging system overlaying the assay plate wherein a scanning light propagates by total internal reflection within an optical waveguide. The waveguide includes a plurality of pixel locations, each aligned with a well in the assay plate, at which total internal reflection is selectively frustrated to output an incident beam of light. That light illuminates the well and causes generation of an emission beam of light that is detected by a photoreceptor. The device further includes a driver circuit that controls the selective frustration of total internal reflection at each pixel location in order to scan each well in the assay plate. A processor is also included in the device to process the detected emission beams of light generated by the scanned wells for purposes of assaying the biological sample contained in each scanned well.
摘要:
The disclosure is directed toward an optical excitation/detection device that includes an arrayed plurality of photodetectors and discrete photoemitters, as well as a method for making such a device. A CMOS fabricated photodetector array includes an arrayed plurality of photoreceptor areas and photoemitter areas, wherein each photoreceptor area includes a CMOS integrated photoreceptor and each photoemitter area includes at least two buried electric contact pads. The CMOS array is selectively etched back at the locations of the photoemitter areas for regions to reveal the buried contact pads. A plurality of discrete semiconductor photoemitter devices (such as, for example, light emitting diodes) are inserted into, and mechanically retained within, the regions of the CMOS fabricated photodetector array. The inserted discrete semiconductor photoemitter devices make electrical contact with the buried electric contact pads that are revealed within each of the regions to form the optical excitation/detection device from an arrayed plurality of photodetectors and discrete semiconductor photoemitters.
摘要:
A sensor array is bonded to or molded together with a micro-lens array to form a sensor cartridge. The micro-lenses of the micro-lens array are configured to focus light incident on the sensors, into the sensors. An alignment structure has a mating profile that receives and engages one or more micro-lenses from the micro-lens array to laterally align the cartridge to enable repeatable precise positioning of the cartridge.
摘要:
A laser system capable of providing light of high intensity is disclosed. This system includes a laser gain medium and three reflectors. A first reflector and a second reflector spaced from the first reflector define a laser cavity that contains the laser gain medium. The second reflector has a reflectivity (R.sub.2) larger than the reflectivity (R.sub.1) of the first reflector such that light emitted from the laser gain medium resonates in the laser cavity. A third reflector having a reflectivity (R.sub.3) larger than the reflectivity of the first reflector (R.sub.1) is spaced from the second reflector to define a resonant cavity external to the laser cavity. Light passes from the laser cavity to resonate in the external resonant cavity. Part of the light passes from the external resonant cavity to the laser cavity to optically lock the laser gain medium.
摘要:
An accurate and reliable pneumotachometer with annular ring transducers for determining the velocity of a fluid flow is provided. A novel and accurate flow measurement system for measuring transit time of a fluid flow using chirp signals and a pneumotachometer with annular ring transducers is also disclosed.
摘要:
A laser system capable of providing light of high intensity is disclosed. This system includes a laser gain medium and three reflectors. A first reflector and a second reflector spaced from the first reflector define a laser cavity that contains the laser gain medium. Light reflected by the first reflector is amplified by the laser gain medium. A third reflector is spaced from the second reflector to define a resonant cavity external to the laser cavity. Light passes from the laser cavity to resonate in the external resonant cavity. Part of the light passes from the external resonant cavity to the laser cavity. A light-screening device, e.g., an aperture, is disposed between the second reflector and the gain medium to screen light reflected from the external cavity such that the light portion of constructive interference is preferentially passed over the light portion of destructive interference. This enables the gain medium to optically lock to the resonant frequency of the external cavity.
摘要:
Method and apparatus for determining the composition and concentration of gases present in a patient's airway by measurement of the spectrum of Raman scattered light from these gases. The efficiency is improved by collecting Raman scattered light generated outside the collection region. The gases present are assumed to be drawn from a predetermined set of gases with known Raman scattering spectra, and the concentrations are determined by solution of a matrix equation Ac=b, where the c vector components are the unknown concentrations and the b vector components are determined from measurements of the Raman scattering intensifies in a plurality of wavelength or wavenumber intervals. The linear system of equations represented by the matrix equation may be overdetermined and may require solution by non-conventional methods, such as singular value decomposition.
摘要:
A method and apparatus for performing dark signal correction on a photoelectric conversion device. A flow of light to the device is alternately conducted and interrupted. The device generates an intermixed signal while the flow of light is conducted to the device, the intermixed signal including a desired signal intermixed with an unwanted dark signal. The device generates a dark signal alone while the flow of light to the device is interrupted. The dark signal alone is filtered to produce a filtered dark signal. The filtered dark signal is subtracted from the intermixed signal to produce a corrected signal, which is representative of the desired signal.
摘要:
A programmable ultrasonic thickness and acoustic velocity measuring instrument is provided which includes automatic zeroing (calibrating) means, automatic temperature compensation and high temperature warning means, automatic probe identification means, means for automatically correcting the measurement readings for probe characteristics, means for storing and displaying of the minimum wall thickness during a predetermined time interval, and means for providing a display indicative of the difference between a measured thickness and a preprogrammed value.