Have just ordered an el cheapo 1.5" picture viewer from ebay. Its only 128x128 resolution but for £4 I thought I might as well crack it open and see what I could do.

I seem to be getting smaller and smaller.

First a 15" OHP, then my in progress portable DVD player and now this.

Plan is to use LEDs for light source. Not sure about lenses yet. Still looking for a keychin size triplet

I might go as far as to make it completely battery powered. Of course it isnt going to win any resolution or brightness awards but will be pretty cool if it works. Challenge will be doing everything in miniature.

If all goes well I may try and get a higher res LCD.

Have looked for lenses ands may have a go with a couple of pocket frensel magnifiers (the credit card size) and a pocket triplet lens. Like a jeweler's lens. As each is only a few quid I wont be breaking the bank to experiment with them.

Looking forward to your progress. Might be neat to be able to project your digital pictures onto a wall for everyone to see. But i think with a res of 128 by 128 the image would get the screen door effect very very quickly and evidently have a very gross looking image. But who knows!

Yeah, I wonder how big I can get away with. Might end up hunting out a higher res screen.

I might have a google when I get the screen and see if there is an easy video pin from the picture viewer to the LCD that I can intercept to feed an external source to.

While its all very well having nice cheap items on ebay, unfortunately they come from Hong Kong so annoyingly im goign to have to wait a few weeks. Im so impatient

Well while I waited I decided to solder up the decent LEDs from my testing (http://www.lumenlab.com/forums/index.php?s=&showtopic=28843&view=findpost&p=311479) onto a board the same size as the LCD. While a couple of them have a slightly lower colour temperature, im going to put a few bi-colour (red/blue) LEDs on the board in the gaps and have them controlled by a little dial so I can fine tune the temperature.

The light from the array is pretty scattered due to the large viewing angle of the surface mount LEDs in the middle. However I have found some lenses that remedy this. Problem is that they cause the opposite to happen and there are dark spots between the LEDs. So im probably going to have to use some sort of diffuser too. But ill see how this looks with the LCD when it arrives first.

PICS:






And the array in comparison to a little 3 LED light from IKEA:





I think i'd better stop this now. I have green and red dots in my eyes and a headache

While im waiting for the parts for it, I have made up a little Mechano testing rig. The picture already has the LEDs in.

Well the jeweler's triplet lens arrived today. Just waiting on the fresnel.

With regards to the LEDs, the large ones in the middle appear to be getting a hot spot on the back so I may cut out the back of the copper stripboard and attach a little RAM heatsink. Pics to come when i figure out how to mount it in the little mechano rig.

Update: Got all the bits, took appart photo frame. (Pics below).

Found that my LEDs dont work very well in this setup as they arent close enough together to give a spread source and so i get dots of bright picture. The diffuser I took off the backlight helps but lessens the brightness.

The best results so far have been from a £3 21LED headtorch I got from ebay. The LEDs are close enough to give a spread and its pretty bright (in comparison ). Only problem is that the corners get cur off because its a circular torch.

Pics of this to come. Ill probably have to find a brighter light source. I also need to do some searching around to see if i can find the pin that sends the signal to the screen and if it is in a nice format (eg: composite) so i can hijack it. This will be harder than the DVD player though because its all SMD and FFS. No nice wires to chop.

Before:


After:


Half Covered Light with LCD

awesome, great work. had i the money I would do this with a video player. would the diffuser with the circular head torch help with the corners?

let me help you out

http://www.instructables.com/id/How_to_mak..._LED_Projector/

hope that link helps (its not mine)

Ooh. Thanks. I had suspected that a single more powerful LED may have been the answer.

Hey Blaize, did that jeweler's triplet work out for you? I tried something similar a few weeks ago and the only problem I had was that I couldn't find a suitable triplet. I tried magnifying glasses, convex lenses, binoculars,etc and couldn't get anything more than the middle .5" of the screen to focus. :/ I can't believe I didn't think of a jeweler's triplet.
BTW I used a Luxeon LED from digikey. Worked quite well.

my own experience.

Materials:

1 lens - scavanged from binocular eyepiece, the eye had two lenses, the lens I used is thick and convex on one side, the other lens is thin and convex on both sides.
1 Ipod mini video
Cardboard
1 Brightly colored Disney cartoon (Robin Hood)

I made a small box that held the Ipod. In box side facing the Ipod screen I mounted the lens.

Seriously it was that simple. The size of the screen at 6feet(aprox) was 3.5 - 4 feet long and 2feet in height. It was focused.

The obivious problem was light, only brightly coloured videos were worth watching. I tried watching IT Crowd with it but too dark.

Point being, a single lens with a good light source should work great.

(The ipod broke before I could do any modifications for a different light source.)

I am building one as well. I just purchased an 1vo sound 880m and loaded Transformers 2. I only paid 38.00 for the player. I plan on using the 3d lens small freshnell lenses and an xenon light source or led. I have a slide projector lens that I got from surplus shed.