A few years ago there were many projects online for DIY projectors, often based on overhead projectors (which are pretty easily available secondhand). However, nowadays you can buy pretty good projectors - even LED projectors -at such a low price that the effort of designing and making one is hard to justify.
I do like this guy’s workmanship, and the lens he is using is probably higher quality than the lenses in any of the three projectors I have. I’d personally be more interested in a project to make a digital version of the camera it was from.
Well, now that we have a proper light source, the expense is pretty much all in the optics. A project like this becomes pretty tempting if you happen to have the skill, and a suitable lens lying around…
Not completely. When you use a passive display, like an LED from a tablet in this project, your color gamut is limited by the gamut of the backlight, and your black levels will be limited by the ability of the panel to block light. Most “white” LED is really blue LED with a filter mask, so good LED projectors use special “phlatlight” LEDs, which are rather expensive, and they use a light processing technology (DLP) for the pixels based on millions of tiny mirrors which can produce more saturation in the spectra at which the LED produces less energy. Getting the colors right (and the blacks black enough) in an LED projector is a hard technical problem, which is why it has taken so long for decent LED projectors to show up for under $500.
Projecting even a quality LED light through an LED panel display is never going to be as good. There are several companies selling very cheap LED projectors based on simple LED technology (right now Fry’s has one for sale for $130), they’re probably OK for kids cartoons or camping or office slide presentations, but not as a TV substitute.
It looks like a cool project… it probably just got lost in the shuffle. It happens sometimes, I’ve noticed. I miss something that I would have loved to have read/discuss, because I’ve not had time to post for a day or two… or I get bogged down in an argument or some such and miss it.