These are all over ebay. Basicly, you're buying a thing called a frensel lens. You have to construct a little box that fits over your monitor/tv screen with the lens on the other side. When you turn of all the lights, the frensel lens is supposed to enlarge the image. Quality sucks, and in many cases people report that can't get it to work (but as you can see from that pic, it is possible). P.S. I just found out that frensel lenses are/were used in lighthouses. edit: d@mnit, ouija, you posted before me (grr...)
ive heard some bad experiences with these things, you cant really go wrong for the £3 or however much they are but then again its whether its really worth it // whoooooooo 100th post
my mate bought two of these (two to get the picture the right way up), they worked, but not very well, quality wasent good , had to turn the brightness right up to get a better pic
Lol, if a decent home projector (Sanyo Z2) costs £999, what do people think they'll get with a £3 lens?
A diy big screen option would involve a fresnel (not one off ebay though as they're the wrong size), a focusing lens, a large light source (such as a metal halide lamp with ballast) and an lcd screen. Shine the light through the lcd panel, the light from this is spread by the fresnel, and then focused by the other lens. You're looking at about 200gbp to construct a fairly decent quality diy projector. The fresnels of ebay are total crap and a waste of time and money If you seriously want a big screen, I may well have a project log coming soon
Love to see it soon Seriously, it's not bad considering how cheap it is. It's good enough quality that you can see everything and make it out. You just won't be able to read text.
Ohhh la spam spam! Might be cheaper to rape a TFT and a OHP....especially one of those flat thin OHPs...
flat, thin ohp's won't work they beam a light down onto the paper(or tft), which is then reflected onto the wall/screen. all you'd get is a blur on your wall... you need a proper old style ohp which will light behind the panel (as backlighting does when tft's are in their casing) this transmitted light is then focused by the adjustable lens and mirror bit at the top of the ohp, giving a nice clear image on your screen/wall if anyone's serious about doing this, a quick look at the video section over at diyaudio should help my prototype should be operational within a day or two edit: a new flat reflective ohp costs in the region of 400gbp btw... ebay is your friend with this kind of project
I was thinking that. School surplus sales/contacts in a school might help too. You can pick up a 14" LCD TV from Sainsburys for something like £140. El cheapo, but has both built in tuner and D-Sub input. So, for around £200-300 you could have your own projector TV. Although be warned - OHP Bulbs blow alot faster than specially made ones for videoprojectors. The replacements are something like £45
I've made mine for under £150 all-in (well, if you dont include the pc that everything runs through ie dvd, mp3, divx, tvcard, ps2, emulators, games) Replacement ohp bulbs range from £3 to £45, replacements for mine are ~£9 each, or £10 for two on ebay As soon as I have time, and can be arsed, i want to take it all apart and put it in a custom enclosure. I might consider messing about with the lighting rig, switching out the bulbs for ones that i can replace for £1 each from a local store
