Accession Number : ADA194220

Title :   Array Detectors for Plasma Spectrochemistry.

Descriptive Note : Technical rept.,

Corporate Author : ARIZONA UNIV TUCSON DEPT OF CHEMISTRY

Personal Author(s) : Denton, M B ; Bilhorn, Robert B ; Pomeroy, Robert S ; Sweedler, Jonathan V ; Epperson, Patrick M

PDF Url : ADA194220

Report Date : 04 Feb 1988

Pagination or Media Count : 6

Abstract : Advanced charge transfer device (CTD) solid state array detectors offer a variety of powerful capabilities for improving spectrochemical analysis. The class of CTD detectors is divided into charge coupled devices (CCDs) and charge-injection devices (CIDs), with each subclass having different readout modes and capabilities. While both subclasses of CTD detectors, when properly operated, provide high quantum efficiency, ultra-low dark current, low readout noise, wide dynamic range and photon integration, CIDs and CCDs possess differing capabilities suited to specific spectroscopic applications. Performance characteristics of several selected devices are presented and contrasted with those of photomultiplier tubes, photodiode arrays and several other imaging detectors. The operating parameters of CTDs including read noise, fixed pattern 'noise', binning, and integration are explained and evaluated for a variety of spectroscopic applications. Techniques for expanded a detector's operational dynamic range are discussed including random access integration (RAI), allowing optimization of the integration time for each different detector element based on the actual photon flux falling on each element during a specific measurement; binning, allowing the combination of charge stored in multiple elements while on the detector; and frame transfer, allowing computer summation of multiple exposures of a single analysis. Keywords: Atomic emission spectroscopy; Direct current plasma; Charge transfer device; Multichannel detectors; Detection limit.

Descriptors :   *ARRAYS, *PHOTODIODES, *PLASMAS(PHYSICS), ATOMIC SPECTROSCOPY, CHARGE COUPLED DEVICES, CHARGE TRANSFER, CHEMICAL ANALYSIS, DETECTION, DETECTORS, DIRECT CURRENT, DYNAMIC RANGE, EMISSION SPECTROSCOPY, FLUX(RATE), FRAMES, HIGH RATE, IMAGES, INJECTORS, INTEGRATION, LIMITATIONS, MEASUREMENT, MULTICHANNEL, NOISE, OPTIMIZATION, PATTERNS, PHOTOMULTIPLIER TUBES, PHOTONS, QUANTUM EFFICIENCY, RANDOM ACCESS COMPUTER STORAGE, RANGE(EXTREMES), READING, SPECTROSCOPY, SPECTRUM ANALYSIS, TIME, TRANSFER

Subject Categories : Physical Chemistry
      Electrical and Electronic Equipment

Distribution Statement : APPROVED FOR PUBLIC RELEASE