Home made projector

A|Hannibal · 27 May 2009 at 18:53

Hi all, new here and looking for some help. Tried searching but not spotted anything.

I'm planning on making a home made projector. To do this I need a small screen, preferably about 2.5" on a device that has AV in. For cheap if possible obviously. I've looked around a lot and can't find anything that fits the bill. I was wondering if anyone here might have any ideas.

Apologies if wrong forum.

The projector is for a home made version of M$ surface by the way.

daz · 27 May 2009 at 18:57

How much are you looking to spend?

You can get half decent new projectors for less than £400 these days... second hand you can go even lower. OHPs aren't cheap and neither are the kind of bright bulbs you need (Mercury-Xenon arc lamps are standard, aren't they?) if you're building it yourself... i'm just questioning how much money you're saving.

geuben · 27 May 2009 at 18:57

I'm not sure about the screen, but I made a multi-touch table this year as part of a uni project, check out www.nuigroup.com for loads of info on making your own.

We used a projector, but there is another method of using an LCD instead. My uni just got a 46" touch screen made from an LCD TV, now obviously an LCD of that size is going to be pretty expensive (I'm assuming that your wanting to build a projector due to cost), but you could make a smaller one.

Edit: In fact, one of the surfaces shown on the homepage at nuigroup is the same as the one we just got at uni (the finnish made one)

A|Hannibal · 27 May 2009 at 19:01

I won't be using an OHP to make mine, and I'm making this mor for fun than to save money.

The design I'm using requires a small screen. This is primarily to reduce the bulk of the overall device, obviously the bigger the screen the bigger the box.

I deally I want to spend under £75. I'm not looking for a great device. Just need the screen and the input.

Was just given the Nuigroup link today, not had a chance to read through it.

geuben · 27 May 2009 at 19:03

A|Hannibal said:
I won't be using an OHP to make mine, and I'm making this mor for fun than to save money.

The design I'm using requires a small screen. This is primarily to reduce the bulk of the overall device, obviously the bigger the screen the bigger the box.

I deally I want to spend under £75. I'm not looking for a great device. Just need the screen and the input.

Was just given the Nuigroup link today, not had a chance to read through it.

Are you planning on turning the little screen into a projector or actually making a 2.5" multi-touch screen?

Edit: Try looking for 2nd hand portable dvd players, I know I have one at home that has AV input.

A|Hannibal · 27 May 2009 at 19:24

lol, not making a 2.5" touch screen. I'll be turning it into a projector. Hadn't thought of one of them. Thanks.

Will post some pics of the project when it's under way.

geuben · 27 May 2009 at 19:25

A|Hannibal said:
lol, not making a 2.5" touch screen. I'll be turning it into a projector. Hadn't thought of one of them. Thanks.

Will post some pics of the project when it's under way.

I think you might run into some problems with brightness and image quality, what sort of lens are you using?

The only issue with a dvd player is the naff resolution.

dave-lew99 · 27 May 2009 at 20:20

I've done this before, just to see what it would be like -

Old 15" TFT screen, 1024x768 res
Old OHP - £20 from the bay

I took the screen apart and stripped it from the backing/mount, placed it onto the top of the OHP and it worked like a charm...

...apart from the bulk, noise, uneven lighting, low brightness and resolution that is!

As an aside, you can make a multitouch projector by using a WiiMote

http://johnnylee.net/projects/wii/

geuben · 27 May 2009 at 21:40

dave-lew99 said:
snip..

As an aside, you can make a multitouch projector by using a WiiMote

http://johnnylee.net/projects/wii/

That still requires a projector and you have to make some IR "pens" (basically and IR LED and a battery).

A|Hannibal · 28 May 2009 at 21:05

well I've got a portable dvd player, screen is bigger than I'd like but it was free so I'm not going to complain.

The main problem I have now is that I can't find an S video to av in cable. The port looks like a typical 3.5 jack would fit but having murder trying to find cable online.

geuben · 28 May 2009 at 21:09

A|Hannibal said:
well I've got a portable dvd player, screen is bigger than I'd like but it was free so I'm not going to complain.

The main problem I have now is that I can't find an S video to av in cable. The port looks like a typical 3.5 jack would fit but having murder trying to find cable online.

The cable is a 3.5mm jack to 2 or 3 RCA jobbies, (2 for mono sound and 3 if it does stereo), you'll then have to find a cable for the TV out on your graphics card that goes to composite and possibly get an RCA female to female connector to join the two cables.

A|Hannibal · 28 May 2009 at 21:13

Gotcha, means I'm going to have more connectors than I was expecting but it's still doable.

geuben · 28 May 2009 at 21:15

A|Hannibal said:
Gotcha, means I'm going to have more connectors than I was expecting but it's still doable.

Yeah it's really not ideal but you must have expected that when you started trying to build a projector

I don't think you can get a svideo to 3.5mm jack cable...well at least not the type you would need.