Accession Number : ADA133591

Title :   Displaying Colors of Specified Chrominance on a Color Graphics Display.

Descriptive Note : Technical rept. Feb-Dec 82,


Personal Author(s) : Gutmann,James C ; Rogers,Steven P

PDF Url : ADA133591

Report Date : Dec 1982

Pagination or Media Count : 54

Abstract : A technique for displaying colors of specified chrominance is reviewed. The technique makes use of models of the bits-to-luminance transfer function of the phosphors of a color graphics system CRT. Measurements of the transfer function of a graphics system were made. Second order polynomial models were found to provide a good fit of the bits-to-luminance relationship. A two-part model or spliced fit approach yielded the most accurate predictions of luminance. The algebraic basis of the technique is reviewed as are the limitations of the technique. Example solutions for graphics system inputs yielding colors of specified chrominance are provided. The technique provides a method for control of color mixing and for quantitative specification of colors. The incorporation of models of the bits-to-luminance transfer function simplified the procedure used to solve for color graphics system bit values. The technique developed need not be limited to use with color CRTs. Once the input-to-luminance output relationship of any display has been measured and characterized, and once the color coordinates of the system's primaries are known, the technique for determining system inputs can be applied. The only restriction is that the CIE color coordinates of the display system color mixing primaries must not vary as a function of luminance output. (Author)

Descriptors :   *Computer graphics, *Chromaticity, *Luminance, Colors, Display systems, Models, Transfer functions, Phosphors, Cathode ray tubes, Measurement, Polynomials, Fitting functions(Mathematics), Predictions, Input, Mixing, Quantitative analysis, Specifications, Output, Coordinates, Linear algebraic equations, Human factors engineering

Subject Categories : Electrooptical and Optoelectronic Devices

Distribution Statement : APPROVED FOR PUBLIC RELEASE