Abstract: The most part of calculating time in the traditional ray trace method is on the intersect judgment, so upgrading on this process is the key to improve the main calculating efficiency. A new technique named shortcut method was presented based on the fact that most nearby rays took a same reflection trace. So one ray was really calculated and its trace called shortcut was recorded as the reference to give direction to other rays next to it. The overwhelming search for the intersect point was avoided and the number of the really calculated rays was reduced a lot. By programming examination, the optimization arithmetic is proved to be fairly precise, remarkably efficient, and also practical.