DIY 720p Projector
I wanted to build a projector from parts and see what I could do!
First up I needed a light source, for this I used a 400 watt metal halide bulb. This was very cheap (~$40 for the ballast and $10 for the bulb) and output a ton of light. The downsides were the amount of heat generated and the size and weight of the ballast. I used an ikea mixing bowl as the reflector to get as much light to the front of the box as possible.
The first iteration of the enclosure and projection lens focusing mechanism was not pretty but it worked. The stain looks silly…
The insides, in the back you can see the ike mixing bowl reflector and 400 watt metal halide bulb. Then there is a fresnel lens that takes the light and projects it straight through the lcd. The lcd was scavenged from a 720p monitor, so the control board and power supply are seen in front of it. The light then comes out of the lcd, and goes through a 2nd fresnel lens which projects it perfectly onto the front projection lens. All of these distances were important to have a focused image with maximum brightness and nothing cutoff.
First test image!
My first focusing mechanism did not work well at all. This is the new and improved shower drain focus mechanism. The best part about this is that you can just screw the lens in and out to move linearly and stay perfectly square, while allowing you to adjust your focus, perfect!
The beginnings of the table that I would put this monstrosity in. This diy projector was huge so my plan was to “hide” it inside the table, instead of in the back of the room or behind the couch area.
The top of the table pieced together, glue and screws holding it together, receives its final layer of polyurethane.
The finished product!
What makes it all worth doing!
Some basic specs for my projector are as follows
720p resolution (uses a 1280×800 lcd monitor) Accepts vga inputs, but I have a vga to component converter to use component sources
Thermostat set to 80 degrees F. When the projector is on, the cooling fans run, and then when switched off, the fans continue to run until the ambient temperature inside the box reaches 80 degrees.
Parts list:
Standard Triplet 220 and 330 fresnels 400watt mh ballast 400w bulb and mogul(gold-blue, silver-white just a note that i am making for myself on hooking up the mogul) x2gen MW15A widescreen 15 inch lcd (1280×800 res) ffc extension for the lcd 1/2 inch birch plywood for the enclosure 2 120mm quiet case fans various switches, power input modules, terminal blocks ikea stabil boiler reflector attic thermostat
Table: ripped 2×4’s into 2×2’s and built a frame. Then put 1/2 inch birch plywood over it. I made a pine surface and used rub on polyurethane for a few coats and then clear coated it with a lacquer
Total cost for entire build (including the small trips to home depot): $600
I originally had a build log on a forum called lumenlab. A user there contacted me from Popular Science and asked if they could do a feature. A photo crew came to my apartment and made me pose like a goober but overall it was a fun experience. Here are some of the clippings from the feature.
