Accession Number:

ADP003447

Title:

A Wide Field-of-View CRT Projection System with Optical Feedback for Self Alignment,

Descriptive Note:

Corporate Author:

EVANS AND SUTHERLAND COMPUTER CORP SALT LAKE CITY UTAH

Personal Author(s):

Report Date:

1983-11-16

Pagination or Media Count:

9.0

Abstract:

Evans Sutherland has developed a multi-channel CRT projection system. This system uses microprocessor technology with optical feedback to provide self-alignment for color-hue, intensity, color-convergence, geometry, and focus. By replacing drift-prone analog correction circuits with digital circuits and DA converters, system drifts are limited to gain and offset errors. These errors are optically detected and corrected in real-time by the microprocessor. Geometry drifts can be detected and corrected to within 14 of a pixel. Because this projection system is CRT based, image generator, lens, and projection angle induced distortions as large as 30 can be corrected by the projectors digital electronics. The projection system self-alignment capabilities together with edge matching make possible the tiling of multiple channels. This facilitates improved brightness and resolution over wide fields-of-view. A six channel system, with 30 degree by 30 degree fields-of-view for each channel, using a 12 foot radius screen of unity gain yields 7 ft-lambert brightness with better than 3 arc-minute resolution. Author

Subject Categories:

Distribution Statement:

APPROVED FOR PUBLIC RELEASE