A projector or image projector is an optical device that projects images onto a surface, commonly a projection screen. Most projectors create an image by shining a light through a small transparent lens, but some newer types of projectors can project the image directly, by using lasers. Video projectors are digital replacements for earlier types of projectors such as slide projectors and overhead projectors. The newest types of projectors are handheld projectors that use lasers or LEDs to project images. Their projections are hard to see if there is too much ambient light.