In the past, video projectors produced color images through shining white light from a rotating color wheel. That all changed when LEDs and lasers were invented.
Researchers at Dartmouth College, along with Disney Research Zürich, have invented a new way to project color images — using prisms and a precise black and white image that is computer-generated.
The key to how the system works is that white light is in fact a combination of all colors. Basically, a color source image is passed through an algorithm that creates two unique images in black and white, which are used as masks and placed on both sides of a prism. The first image is full of small slits and is placed in front of the prism, producing thousands of small dots, or pixels, which are rainbows as light passes through it. The second image sits behind the prism, blocking colors of the rainbow not needed for the image.
Basically, there are no visible colors until the final image is projected, which is pretty remarkable considering how other projection technology works today.
The resulting images aren't anywhere near as sharply vibrant as images you could get from technology today, but there is potential for that to be improved. Not only that, but the parts needed to create this projector only cost around $30, so the technology has a lot of potential for making the devices more affordable. In fact, with this technology, one day, the flash on the back of a smartphone could double as a projector.
Via: Gizmodo
