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Substrate-Independent Technique of III-V Heterogeneous Integration of Focal Plane Arrays and Lasers.
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Design and simulation of a snapshot multi-focal interferometric microscope
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Image translation for single-shot focal tomography
Focus and depth of field are conventionally addressed by adjusting longitudinal lens position. More recently, combinations of deliberate blur and computational processing have been used to extend depth of field. Here we show that dynamic control of transverse and longitudinal lens position can be used to decode focus and extend depth of field without degrading static resolution. Our results suggest that optical image stabilization systems may be used for autofocus, extended depth of field, and 3D imaging.
Precision Laser Annealing of Focal Plane Arrays
We present results from laser annealing experiments in Si using a passively Q-switched Nd:YAG microlaser. Exposure with laser at fluence values above the damage threshold of commercially available photodiodes results in electrical damage (as measured by an increase in photodiode dark current). We show that increasing the laser fluence to values in excess of the damage threshold can result in annealing of a damage site and a reduction in detector dark current by as much as 100x in some cases. A still further increase in fluence results in irreparable damage. Thus we demonstrate the presence of a laser annealing window over which performance of damaged detectors can be at least partially reconstituted. Moreover dark current reduction is observed over the entire operating range of the diode indicating that device performance has been improved for all values of reverse bias voltage. Additionally, we will present results of laser annealing in Si waveguides. By exposing a small (<10 um) length of a Si waveguide to an annealing laser pulse, the longitudinal phase of light acquired in propagating through the waveguide can be modified with high precision, <15 milliradian per laser pulse. Phase tuning by 180 degrees is exhibited with multiple exposures to one arm of a Mach-Zehnder interferometer at fluence values below the morphological damage threshold of an etched Si waveguide. No reduction in optical transmission at 1550 nm was found after 220 annealing laser shots. Modeling results for laser annealing in Si are also presented.
CMR Oxides Based Microbolometer Focal Plane Array with Reduced i/f Noise: CRADA Final Report
Los Alamos National Laboratory and the CRADA Participant deposited La0.7Sr0.3MnO3 films on different substrates by both pulsed laser deposition and polymer-assisted deposition. The structural and transport properties of the films were characterized.
Astronomical Spectroscopy with Skipper CCDs: A Skipper CCD Focal Plane Prototype at SIFS
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Enabling High-Speed, High-Resolution Space-based Focal Plane Arrays with Analog In-Memory Computing Presentation Slides
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Substrate-Independent Technique of III-V Heterogeneous Integration of Focal Plane Arrays and Lasers
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CTN-001: LSSTCam and LSSTComCam Focal Plane Layouts
This document includes figures depicting the layouts of the LSST Camera and LSST Commissioning Camera, highlighting the arrangement and identification of science, wavefront, and guider sensors, as well as their individual readout image segments.
The role of microorganisms in the weathering of rocks. 2 - Focal distribution of microorganisms on the surface of rocks
Microorganism growth in synthetic medium using rock as mineral nutrient source, and rock weathering due to microorganisms
Electronics for a focal plane crystal spectrometer
The HEAO-B program forced the usual constraints upon the spacecraft experiment electronics: high reliability, low power consumption, and tight packaging at reasonable cost. The programmable high voltage power supplies were unique in both application and simplicity of manufacture. The hybridized measurement chain is a modification of that used on the SAS-C program; the charge amplifier design in particular shows definite improvement in performance over previous work.
Focal plane transport assembly controls for the High Energy Astronomy Observatory X-ray telescope
The High Energy Astronomy Observatory - Mission B (HEAO-B) is a satellite observatory for the purpose of performing a detailed X-ray survey of the celestial sphere. Measurements will be made of stellar radiation in the range of 0.2 to 20 keV. The central part of the Observatory is an X-ray telescope, into the focus of which a variety of imaging instruments and spectrographs may be introduced. The telescope has a resolution of about 1 arc second, so that the instruments must be placed with extreme precision. This is obtained by a mechanical system of toggles and stops and a motor drive system controlled by a position sensing potentiometer with a resolution of about 1.5 degrees
Effects of altitude, focal length, and filter combinations on color infrared photography of citrus groves
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Thematic mapper flight model preshipment review data package. Volume 4: Appendix. Part D: Focal plane assembly data
The data obtained for the Band 1 thematic mapper flight full band assembly (P/N 50797) are summarized. The data were collected from half band, post amplifier, and full band acceptance test data records.
Test results of Spacelab 2 infrared telescope focal plane
(Previously announced in STAR as N81-28020)
Improved charge injection device and a focal plane interface electronics board for stellar tracking
An improved Charge Injection Device (CID) stellar tracking sensor and an operating sensor in a control/readout electronics board were developed. The sensor consists of a shift register scanned, 256x256 CID array organized for readout of 4x4 subarrays. The 4x4 subarrays can be positioned anywhere within the 256x256 array with a 2 pixel resolution. This allows continuous tracking of a number of stars simultaneously since nine pixels (3x3) centered on any star can always be read out. Organization and operation of this sensor and the improvements in design and semiconductor processing are described. A hermetic package incorporating an internal thermoelectric cooler assembled using low temperature solders was developed. The electronics board, which contains the sensor drivers, amplifiers, sample hold circuits, multiplexer, analog to digital converter, and the sensor temperature control circuits, is also described. Packaged sensors were evaluated for readout efficiency, spectral quantum efficiency, temporal noise, fixed pattern noise, and dark current. Eight sensors along with two tracker electronics boards were completed, evaluated, and delivered.
Lead sulfide - Silicon MOSFET infrared focal plane development
A process for directly integrating photoconductive lead sulfide (PbS) infrared detector material with silicon MOS integrated circuits has been developed primarily for application in long (greater than 10,000 detector elements) linear arrays for pushbroom scanning applications. The processing technology is based on the conventional PMOS and CMOS technologies with a variation in the metallization. Results and measurements on a fully integrated eight-element multiplexer are shown.