OK so im in the process of building an LCD projector using an old portable DVD player. Everything is built but i need ideas/input for lighting and lens. It will be for use in my car.
Im using a horizontal 4"x3" LCD display (handy 4:3 ratio) lighting from underneath with a mirror at 45 degrees above it, all being projected though a vertical lens.
I need to know what lens focal I sould be looking for for a 3-5ft projection range, with a x5 size (20"x15")appx. Im currently using a achromatic lens from a pair of binoculars, but it gives a throw to big to close.
The Key thing I need is a light source. I prefer LED's, or another low-power, low-size alternitive. The whole project budget is 50-60$ and so far is quite possible. I could use some input as too what would be ideal for lighting thats low power/low cost. The device can run on a single battery (from the dvd player) for 2 hours with the backlight. Id like to make a seprate backlight using perhaps using an addition car-recharge battery.
my set up works, but the only light I have is the LCD's backlight, which needless to say is worthless and will only project a few inches before the light dims beyond comprehension.
Im only 16, and my wallet isnt huge. I have a pretty good understanding of optics/electronics, enough that got me this far with no guides/ no help. But there coems a point when advice is a vaulable commodity.
Thanks
(I'll post some pictures once they're taken.)