mechtopia

DLP: The end of the rainbow?

It's generally acknowledged that DLP projectors have the edge over LCD in many respects, with great colour reproduction, great contrast ratios and the ability to project 3D movies with shutter glasses, but there's one thing I believe that is preventing many DLP projectors from winning all the awards, and that is the colour wheel.

The colour wheel is a way of processing all of the colour information with a single light path (LCD projectors, for example, need to create a separate beam of light for each colour, then recombine them) by spinning a coloured wheel - this projects each colour rapidly in sequence.

Having one path means you only need one DLP chip, and this lowers costs, but it has two side effects: The first is the sound of the colour wheel : LCD projectors have been engineered to produce virtually no noise in use, but DLP projectors have two sources of noise to get rid of - both the fan, and the colour wheel. The second issue is one that affects me personally, and that's the rainbow effect. Despite the fact that the colour may be switching hundreds of times a second, this is still slow enough for many people to detect rainbows as their eyes flit around their scene. This is not only annoying, it gives me a headache after around 15 minutes of viewing.

Even if you don't suffer from this yourself, it might affect one of your friends.

Three chip DLP projectors use a chip for each colour, combining the best of both worlds. Unfortunately they're still very expensive. Only when this happens might it might usher in the end of the LCD projector.

Posted at 01:56PM Oct 26, 2009 by ohp in General  |  Comments[0]