Restricted accessResearch articleFirst published online 1981-5
Applications of the Optical Multichannel Analyzer for Low Light Level Signal Averaging and Two-Dimensional Mode Detection of Picosecond Laser-Generated Raman Spectra
Techniques developed for the use of a programmable optical multichannel analyzer are discussed. Two different signal-limited areas which are of general spectroscopic interest are the focus of the paper. The first area involves using extended delay target integration techniques for low level light signal averaging. The second application area describes techniques developed for capturing spectral information from pulsed laser experiments. Multiple tracks are shown in order to demonstrate the two-dimensional applications in spectroscopy. The paper also contains information about the design and operating principles of vidicon detectors and other imaging technologies are considered as well.
OMA is a registered trademark of Princeton Applied Research Corporation, an EG&G Company, Princeton, NJ.
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Photoelectron losses can occur at a number of places in the intensifier stage. The fiberoptic faceplate and UV scintillator coating introduce losses. Spurious reflections may occur; this often leads to a phenomenon known as halation.
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See Application Notes, for example from PARC or Pacific Precision Instruments (PC-1), Concord, CA.
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For example from Tracor Northern, DARSS, Middleton, WI.
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For example from Reticon, subisidiary of EG&G Company, Sunnyvale, CA.
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For example, from Fairchild Semiconductor, Mountain View, California.
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The detector is actually a 512×512 array. However, because of edge distortions of the target by virtue of the curvature of the photocathode in the design of the electrostatic intensifier, only 500×500 is actually used. In addition, freedom from distortion, i.e., uniformity, is achieved principally in the central region of the target so that normal spectroscopic lineshape information is obtained by using 500 channels and using a central channel height of 250 channels.
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PARC model 1211 high voltage pulse generator. The delay and pulse duration are programmable through the OMA 2 1216 multichannel detector controller.
