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High Technology Sensors, Inc.'s Model SS-250 carbon dioxide detector uses a patented semiconductor optical source that efficiently creates infrared radiation, which is focused through an airway on a detector. Carbon dioxide passing through the airway absorbs the radiation causing the detector to generate a signal. The small size and low power requirements of the SS-250 make it attractive for incorporation in a variety of medical instruments.
The concept, implementation, and performance of the motion detection system (MDS) designed as a diagnostic for X-ray ground testing for AXAF are described. The purpose of the MDS is to measure the magnitude of a relative rigid body motion among the AXAF test optic, the X-ray source, and X-ray focal plane detector. The MDS consists of a point source, lens, centroid detector, transimpedance amplifier, and computer system. Measurement of the centroid position of the image of the optical point source provides a direct measure of the motions of the X-ray optical system. The outputs from the detector and filter/amplifier are digitized and processed using the calibration with a 50 Hz bandwidth to give the centroid's location on the detector. Resolution of 0.008 arcsec has been achieved by this system. Data illustrating the performance of the motion detection system are also presented.
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Proposed random-access-memory (RAM) addressing system, in which memory linked optically to read/write logic circuits, greatly increases computer operating speed. System - comprises addressing circuits including numerous lasers as signal sources, numerous optical gates including optical detectors associated with memory cells, and holographic element to direct light signals to desired memory-cell locations - applied to high-capacity digital systems, supercomputers, and complex microcircuits.
The standard Charpy Impact Tester has been modified by the addition of a system of hardware and software to improve the accuracy and consistency of measurements made during specimen fracturing experiments. An optical disc, light source, and detector generate signals that indicate the pendulum position as a function of time. These signals are used by a computer to calculate the velocity and kinetic energy of the pendulum as a function of its position.
The Timed Doppler Interferometer (TIDI) will accurately and precisely determine the global vector MLTI (Mesosphere and Lower Thermosphere) wind, temperature, and density profiles. It will measure characteristics of the gravity wave and planetary wave spectra. The tidal characteristics of temperature, density, and wind in the MLTI will be determined. The neutral and ion winds will be measured to characterize the electrodynamical behavior of the MLTI. Oxygen and O2 abundances and nocticulent cloud activity will be measured. This review goes into the calibration and error sources, optical design, mechanisms design, detector design, electronics design, microprocessor and flight software design, and quality assurance and parts.
A system and method for determining a reflection wavelength of multiple Bragg gratings in a sensing optical fiber comprise: (1) a source laser; (2) an optical detector configured to detect a reflected signal from the sensing optical fiber; (3) a plurality of frequency generators configured to generate a signal having a frequency corresponding to an interferometer frequency of a different one of the plurality of Bragg gratings; (4) a plurality of demodulation elements, each demodulation element configured to combine the signal produced by a different one of the plurality of frequency generators with the detected signal from the sensing optical fiber; (5) a plurality of peak detectors, each peak detector configured to detect a peak of the combined signal from a different one of the demodulation elements; and (6) a laser wavenumber detection element configured to determine a wavenumber of the laser when any of the peak detectors detects a peak.
A single-source, single-detector architecture has been developed to implement a reconfigurable optical interconnection network multimode optical fiber sensor arrays. The network was realized by integrating LiNbO3 electrooptic (EO) gratings working at the Raman Na regime and a massive fan-out waveguide hologram (WH) working at the Bragg regime onto a multimode glass waveguide. The glass waveguide utilized the whole substrate as a guiding medium. A 1-to-59 massive waveguide fan-out was demonstrated using a WH operating at 514 nm. Measured diffraction efficiency of 59 percent was experimentally confirmed. Reconfigurability of the interconnection was carried out by generating an EO grating through an externally applied electric field. Unlike conventional single-mode integrated optical devices, the guided mode demonstrated has an azimuthal symmetry in mode profile which is the same as that of a fiber mode.
Instrument can measure optical transmission, reflectance, and scattering. This information can be used to identify changes in optical properties or deviations from required optical standards. Device consists of monochromatic source, photo detector, transfer mirror, and hemiellipsoid. System might be used to measure optical properties of thin film.
A random access memory addressing system utilizing optical links between memory and the read/write logic circuits comprises addressing circuits including a plurality of light signal sources, a plurality of optical gates including optical detectors associated with the memory cells, and a holographic optical element adapted to reflect and direct the light signals to the desired memory cell locations. More particularly, it is a multi-port, binary computer memory for interfacing with a plurality of computers. There are a plurality of storage cells for containing bits of binary information, the storage cells being disposed at the intersections of a plurality of row conductors and a plurality of column conductors. There is interfacing logic for receiving information from the computers directing access to ones of the storage cells. There are first light sources associated with the interfacing logic for transmitting a first light beam with the access information modulated thereon. First light detectors are associated with the storage cells for receiving the first light beam, for generating an electrical signal containing the access information, and for conducting the electrical signal to the one of the storage cells to which it is directed. There are holographic optical elements for reflecting the first light beam from the first light sources to the first light detectors.
Narrow band optical filters, galactic X ray source detectors, AM baseband telemetry, and redundancy removal for telemetry data compressions
We discuss the instrumental aspects affecting the measurement accuracy when determining PSD with phase shifting interferometers. These include the source coherence, optical train effects, and detector effects. The use of a carefully constructed calibration standard will also be discussed. We will end with a recommended measurement and data handling procedure.
This paper presents the findings of the trade study to evaluate carbon dioxide (CO2) sensing technologies for the Constellation (Cx) space suit life support system for surface exploration. The trade study found that nondispersive infrared absorption (NDIR) is the most appropriate high Technology Readiness Level (TRL) technology for the CO2 sensor for the Cx space suit. The maturity of the technology is high, as it is the basis for the CO2 sensor in the Extravehicular Mobility Unit (EMU). The study further determined that while there is a range of commercial sensors available, the Cx CO2 sensor should be a new design. Specifically, there are light sources (e.g., infrared light emitting diodes) and detectors (e.g., cooled detectors) that are not in typical commercial sensors due to cost. These advanced technology components offer significant advantages in performance (weight, volume, power, accuracy) to be implemented in the new sensor. The exact sensor design (light source, transmitting optics, path length, receiving optics and detector) will be specific for the Cx space suit and will be determined by the performance requirements of the Cx space suit. The paper further identifies specifications for some of the critical performance parameters as well as discussing the engineering aspects of implementing the sensor into the Portable Life Support System (PLSS). The paper then presents testing results from three CO2 sensors with respect to issues important to Extravehicular Activity (EVA) applications; stability, humidity dependence and low pressure compatibility. The three sensors include two NDIR sensors, one commercial and one custom-developed by NASA (for a different purpose), and one commercial electrochemical sensor. The results show that both NDIR sensors have excellent stability, no dependence on ambient humidity (when the ambient temperature is above the dew point) and operate in low pressure conditions and after being exposed to a full vacuum. The commercial electrochemical sensor was not suitable for the Cx space suit for surface exploration. Finally, the paper identifies a number of techniques currently under development that offer significant advantages for EVA applications. These include miniaturized, room temperature, solid electrolyte systems and advanced optical detectors.
Recent developments in X-ray and hard X-ray imaging detector, high-intensity sources, hard X-ray imaging optics, calibration, and detection technologies are discussed. Particular attention is given to a high-MTF X-ray image intensifier, application of monolithic CdZnTe linear solid state ionization detectors for X-ray imaging, magnetic response of high-Tc superconductors to X-ray radiation and detection of X-rays, laboratory soft X-ray source with foil target, detection of explosive materials using nuclear radiation, energy response of astronomical CCD X-ray detectors, calibration techniques for high-flux X-ray detectors, fabrication of grazing-incidence optics using flow-polishing techniques, and numerical simulations for capillary-based X-ray optics. (No individual items are abstracted in this volume)
A device for separating and purifying useful quantities of particles comprises: a. an anolyte reservoir connected to an anode, the anolyte reservoir containing an electrophoresis buffer; b. a catholyte reservoir connected to a cathode, the catholyte reservoir also containing the electrophoresis buffer; c. a power supply connected to the anode and to the cathode; d. a column having a first end inserted into the anolyte reservoir, a second end inserted into the catholyte reservoir, and containing a separation medium; e. a light source; f. a first optical fiber having a first fiber end inserted into the separation medium, and having a second fiber end connected to the light source; g. a photo detector; h. a second optical fiber having a third fiber end inserted into the separation medium, and having a fourth fiber end connected to the photo detector; and i. an ion-exchange membrane in the anolyte reservoir.
A device for separating and purifying useful quantities of particles comprises: (a) an anolyte reservoir connected to an anode, the anolyte reservoir containing an electrophoresis buffer; (b) a catholyte reservoir connected to a cathode, the catholyte reservoir also containing the electrophoresis buffer; (c) a power supply connected to the anode and to the cathode; (d) a column having a first end inserted into the anolyte reservoir, a second end inserted into the catholyte reservoir, and containing a separation medium; (e) a light source; (f) a first optical fiber having a first fiber end inserted into the separation medium, and having a second fiber end connected to the light source; (g) a photo detector; (h) a second optical fiber having a third fiber end inserted into the separation medium, and having a fourth fiber end connected to the photo detector; and (i) an ion-exchange membrane in the anolyte reservoir.
The 20 keV-3 MeV celestial X-ray detector on the OSO-8 is described. The primary objectives of this instrument are to measure the energy spectrum of cosmic X-ray sources above 20 keV and to search for time variations, both periodic and irregular, in the intensity of the sources detected. The detector consists of two optically isolated central crystals shielded by a large, active collimator. The sensitive area is 27.5 sq cm and the field-of-view is 5 deg FWHM. The instrument is mounted in the wheel section of OSO-8 with the axis of its field of view offset by 5 deg from the negative spin axis of the wheel. The minimum detectable intensity of a point source which is brought to within 5 deg of the negative spin axis for greater than one day is about 10 to the minus fifth power photons/sq cm-sec at 100 keV.
Understanding how materials evolve during synthesis, processing, or device operation requires experimental access to structural dynamics across wide ranges of length and time scales, often in bulk samples or even within packaged devices. Time-resolved full-field diffraction X-ray microscopy has recently emerged as a powerful way to meet this need by combining the penetration and structural sensitivity of X-ray diffraction with objective-lens-based magnification, sensitive high-resolution X-ray imaging detectors, and pump-probe and real-time imaging strategies. Advances in full-field X-ray diffraction microscopy, often termed dark-field X-ray microscopy (DFXM), enable simultaneous imaging of extended fields of view while retaining crystallographic selectivity. Time-resolved DFXM promises to enable advances in materials processing and dynamics, electrochemical and photochemical processes, and the design of electronic devices. This Perspective summarizes the key instrumental concepts that define the performance of these methods, including the choice of imaging optics, detector considerations, and the impact of source time structure at synchrotron light sources and X-ray free-electron lasers (XFELs). We discuss the simultaneous use of complementary imaging modes that are increasingly used in practice. The early demonstrations of the potential of time-resolved DFXM include real-time defect and grain-boundary dynamics during metal annealing, stroboscopic imaging of functional devices with high strain sensitivity, and ultrafast pump-probe implementations at XFELs that directly visualize acoustic-wave propagation and energy dissipation in bulk crystals.