---   DLP PROJECTORS   ---


Understanding DLP Prjector Technology
 -- Jim Gelder, Projectorian.com


DLP (digital light processing) projectors use an all-digital display chip. As opposed to analog systems, the DLP projector uses an optical semiconductor to duplicate source material and manipulate light.


It is very reliable and delivers a high quality picture. DLP technology is now being used by many projector manufacturers in their high-end systems.


A key advantage is its portability, DLP technology can be used in small, ultralight projectors to enable them to deliver a high fidelity picture that rivals much larger units.


The DLP chip is actually a sophisticated light switch, which is an array of up to two million hinged microscopic mirrors. These mirrors are what reflects the digital image onto the screen.


By alternating the direction of each microscopic hinge, the micromirrors will either move towards or away from the light, thereby creating light and dark pixels on the screen. The mirrors are directed by the image code to switch on and off, several thousand times per second. The frequency of switching is what generates up to 1,024 shades of grey in the resulting image.


The DLP projector also handles color very well, by passing the light through a color wheel, which filters the light into red, green and blue, which are the basic elements of all colors. From these three colors, the system can generate 16.7 million colors. In the more advanced three-chip DLP system, up to 35 trillion colors can be generated with spectacular results.


For the best color, contrast, and brightness, DLP is definitely the way to go. The units employing DLP technology are highly versatile, and have a sleek and lightweight form factor.


The DLP unit achieves maximum clarity, since each of the micromirrors are less than a micron apart. By minimizing the gap between pixels, the resulting digital picture is more seamless, and very sharp--without any of the pixelation common to other technologies.


DLP projectors are also useful for presentations that must be made with lights on, the superior light retention of the technology makes the display much more resistant to ambient light.


One downside is light leakage around the mirrors, which generates a sort of halo effect on some images. Newer DLP projectors use a "dark" chip, which uses a dark undercoating on the undersides of the mirrors to eliminate this problem.


This advanced system represents the state of the art, and is perhaps one of the most sophisticated projection systems on the market today. However, it is also one of the most expensive. However, as is the nature of most technology, the prices have already started to decrease on these units.





Lots of good information can also be found at the TI website - where else but at dlp.com, where they have an entire section featuring projector information. I also stumbled upon some instructions for making your own DLP projector from lumenlab.com.