Showing papers on "High dynamic range published in 1979"
04 Dec 1979
TL;DR: In this paper, a novel approach to coherent optical pattern recognition is described, where a 2D input function is described in terms of its absolute normalized invariant moments, and a parallel optical processor with a special mask is used to generate all moments for a 2-D scene in parallel.
Abstract: A novel approach to coherent optical pattern recognition is described. It does not utilize matched spatial filters and optical correlation methods. Rather, a 2-dimensional input function is described in terms of its absolute normalized invariant moments. Comparison of these moments enables one to determine the presence of a given object independent of geometrical distortions. A parallel optical processor with a special mask is used to generate all moments for a 2-D scene in parallel. A simple digital post processor calculates the actual absolute normalized invariant moments with the high dynamic range necessary. Our initial work reported upon here has concentrated on: the optical generation of individual moments, how the individual moments vary, the dynamic range requirements of the system and how they may best be met in a hybrid optical digital topology,and methods to generate all moments optically in parallel.© (1979) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
14 citations
Proceedings Article•
01 Sep 1979
TL;DR: In this paper, the critical parameters of the detector-to-CCD coupling and the related limitations for the various kinds of thermal imaging scanners are discussed, and some experimental results on the direct-injection coupling of a Pb 0,80 Sn 0,20 Te photovoltaic detector array at 77 K to a silicon CCD multiplexer specially designed for the readout of infrared detectors.
Abstract: Because of its low-noise capability, high dynamic range and low power consumption, the CCD appears to be a potentially very useful tool for signal processing of linear and two-dimensional focal-plane arrays of infrared detectors. The signal processing operations include time delay and integration (TDI), multiplexing and filtering. We discuss in this paper the critical parameters of the detector-to-CCD coupling and the related limitations for the various kinds of thermal imaging scanners. Some of these parameters have been measured at 300 K and 77 K, especially the CCD's input transconductance, the input MOSFET coupling noise, the transfer noise in the CCD channel, and the threshold voltage dispersion. We also give some experimental results on the direct-injection coupling of a Pb 0,80 Sn 0,20 Te photovoltaic detector array at 77 K to a silicon CCD multiplexer specially designed for the readout of infrared detectors. At present the 2.1010 W-1 cmHz1/2 measured equivalent detectivity is limited by the coupling noise in the channel of each input MOSFET. A 5.1010 W-1 cmHz1/2 equivalent detectivity is expected with 8 - 12 ?m detectors operated at 60 K.