Optical proximity correction (OPC) is another technique. RET technique is also used in laser printers.
To increase the resolution of laser printers and inkjet printers, Hewlett Packard has developed Resolution Enhancement Technology (RET). The process is similar to the antialiasing used in computer graphics. In RET technology, as in antialiasing, stair-stepped edge and line features are smoothed. The process changes the size of the printing dots on edges and lines so that they appear partially printed on top of each other in the printed image and the colors of the printing dots mix with each other.