In recent years, we have known that LED becomes a reliable source of a projection system due to its flux enhancement, high pure color and the compact size. In this paper, we will discuss a new simple single micro‐display projection system with a high efficiency collimator in it. Due to the LED is emitting to the semi‐sphere space, the collimator is specially designed for its emitting properties. With the novel collimator, a prototype of LED projection display is finished and has over 50% optical system efficiency in it.