Title :
A real time Fourier plane filter
Author :
Aldrich, R.E. ; Krol, F.J. ; Simmons, W.A.
Author_Institution :
Itek Corporation, Lexington, Mass.
Abstract :
An electrically addressed, liquid crystal, fourier plane filter capable of real time optical image processing is described. The filter consists of two parts, a wedge filter having forty 9° segments and a ring filter having twenty concentric rings in a one inch diameter active area. Transmission of the filter in the off (transparent) state exceeds fifty percent. By using polarizing optics, contrast as high as 104:1 can be achieved at voltages compatible with FET switching technology. A phenomenological model for the dynamic scattering will be presented for this special case.
Keywords :
High speed optical techniques; Image processing; Light scattering; Liquid crystals; Optical character recognition software; Optical filters; Optical scattering; Optical sensors; Valves; Voltage;
Conference_Titel :
Electron Devices Meeting, 1972 International
DOI :
10.1109/IEDM.1972.249333
