2004 Volume 43 Issue 2 Pages 112-118
In a laser beam printer, a tone value of each pixel is generated by rasterizing and color transformation. Rasterizing extracts raster data from vector data, and performs expansion, reduction or rotation of an image. The color transformation converts an input color space into an output one of the printer. The tone value is converted into recordable data which is suitable for electrophotography by a record signal processing such as smoothing and halftoning. Smoothing mitigates the jaggy appearance in characters as well as line images. Halftoning reproduces a tone of an image in pseudo by modulating the dot-size or dot-density. In the electrophotographic laser beam printer, since the resolution and the dot reproducing capability are unsatisfactory, various record signal processings have been developed. This paper explains the record signal processings proper to the laser beam printer, and its latest trends.
