Cooling Systems

It is very important that your LCD projector have adequate cooling. Even though metal halide lamps are very heat and energy efficient, they still get hot! In general, all LCD projectors are air-cooled. In the case of DIY projectors, we use PC case fans to cool our enclosures.

Air-Cooled Approach
One thing to remember is that in a sealed enclosure such as your LCD projector, having one fan to exhaust hot air isn't always sufficient since it is hard for fresh air to come in. We recommend using two fans: one for fresh air input and one for hot air output.

You can see in my own personal MkIII enclosure how this is done. The vents were cut 80mm wide with a hole-cutter drill attachment. You can use a jigsaw or something similar for the same effect.

Another air-cooling technique that could be used is to add a heat sink to the system. A heat sink is a metal block with metal fins to dissipate heat more quickly. In most projectors, air cooling is sufficient. If you wanted to add a heat sink to your light source, you could use a "cold mirror" to reflect the visible light onto the LCD panel, and pass all of the IR (heat) rays onto a black metal plate that has a heat sink attached. Why black? Because it will most likely absorb more heat than a shiny surface.

Liquid-Cooled Approach (Experimental)
As some of you may be aware, many new computer modifications involve the use of liquid cooling techniques. The idea behind liquid cooling is that water, or some other liquid, will run through a metal body, possibly between the fins of a heat sink, and absorb most of the heat on their way through. Then the fluid travels to a radiator, just like your car uses, which re-cools the water by using fans. This method is more expensive than simple air-cooled approaches, and it can also be dangerous if not done properly. Currently there is no need for liquid cooling in our projectors because even our most powerful light source runs does not run hot enough to necessitate it.

© 2006 DIY For Life Inc