Control system for a variable-resolution raster output scanner

摘要

A raster output scanner is capable of creating images at a wide range of selectable resolutions. A laser source for creating an image is modulated at a pixel clock rate. A clock command value is determined as a function of a value related to the pixel clock rate and a value related to a desired resolution in the fast-scan direction and a desired resolution in the slow-scan direction of an image to be created on the photosensitive surface. The pixel clock rate is controlled in response to the clock command value. A polygon command value is determined as a function of the value related to the pixel clock rate, a value related to a desired resolution in the fast-scan direction of an image to be created on the photosensitive surface, and a value related to a rotational velocity of the polygon mirror. The rotational velocity of the polygon mirror is controlled in response to the polygon command value.