Computer graphics color film recording method and apparatus

Abstract

A colorgraphics recorder has a cathode ray tube with three parallel strips of light emitting phosphor, each emitting in one of the primary colors, with the light emitted from the phosphors focused on a film frame held in a film carrier. Each of the parallel strips of phosphor on the CRT can have a number of individually illumable pixels, forming a column of pixels. The light from each pixel at the same row level in each of the three strips of phosphor may be focused onto the same spot on the film frame so that all three of the primary colors are exposed at the same time at each pixel in the column of pixels exposed on the film frame. The film frame may then be indexed over one pixel width and the process repeated to expose another column of pixels in each of the three primary colors. Continued repetition of the process across the entire width of the film frame completes the exposure of the frame. Alternatively, the pixels on each of the three strips of phosphor on the CRT may be focused separately onto the film frame, forming three separate columns on pixels exposed in the three different primary colors. The intensity of the pixels exposed for each of the three colors is appropriate for the particular position on the film frame of the column of pixels that is exposed. The film frame is then indexed over one pixel width and the process repeated, with the tracing of the pixels on the CRT selected such that, for example, a column of blue pixels previously exposed on the film frame has a subsequent exposure by a column of green pixels, and another subsequent exposure by a column of red pixels, so that all of the three primary colors for all of the pixels in that column are exposed. This process is repeated, indexing the film frame one pixel width at a time until the entire frame of film is exposed.