DIY Video Projector Part II

[MatrixQ]

Declined:

The way you put in your LCD in the projector is the way it will appear on the screen (i.e. if you put the LCD in backwards, the projected image will be horizontally flipped).

This could, i guess, be overcome with some sort of lens setup if the light going through the LCD backwards was that much brighter, though this is not my department.

But let me know how it turns out, as I would be interested to know if more light flows through the LCD one way than the other.

Desmond.

[declined]

There is a button on my lcd which flips my image so it can be used either way...
Just wondering which side most people use... (it's not an overhead panel)

greetz
Sieg

[MatrixQ]

Ahh. Then I have absolutely no answers for you.

best way is to try it both ways . . . jury rig it up, see which looks better, that'll be the best way. ;oP

Be sure to post here which way was indeed the best way.

Desmond.

[zardoz]

Originally posted by declined
Okay... I have a question that might seem totally stupid but I'm sure there is at least 1 other person that once didn't know this :
What side of the lcd should face the bulb?
My guess would be the back side because the lcd backlight shines through that one... but on the other hand: my lcd has a silverish shine on the back so a lot of light might be reflected back??

Do other people also have lcd's with a shiny silverish back? What did you do? (back to bulb/ front to bulb)

Sounds like you have a panel that doesnt have the same build sequence as mine. Can you give us a breakdown on it construction? See my earlier post on how my panel is put together. My panel's are "Transmissive" there is a designation for panels "Reflective" these have a shiny coating on the back to take the place of the "light pipe" concept that I refered to. If it is reflective...is there any way to remove the coating? (I'd be extra carefull here) I've never had one like this in front of me so cant offer advice on the feasabillity of removing a spray on coating (or a stick on sheet) Hmmm maybe using one of those chemicals on the screen that the laptop manufactures tell us "do not use ****** based cleaning products, as they will damadge the sensitive LCD coating" (this is not advice... just conjecture

zardoz

[JO3L]

any of you gosu diy people out there can you please go to the main video forum and check out my plan.....i need some input before i drop the money for it

[MatrixQ]

Hello all,

I have an opportunity to purchase this overhead projection pannel for $139 USD shipped to my door. I was hoping someone here could tell me if that is a good deal. Being new to this arena, I have absolutely no idea (I'm so out of my league).

The specs of the panel are as follows:

Compatibility MCGA, CGA, EGA, VGA, Mac
Colours 1.7 million
Resolution 640 x 480
Display area 170.9 mm (H) x 129.6 mm (V)
System PAL/SECAM/NTSC
Power requirements 32 W
Dimensions 330 mm (W) x 270 mm (D) x 56 mm (H)
Weight 2.4 kg

Thanks to anyone who can help.

Regards,
Desmond.

[gianni]

Haven't used this particular panel... but check out this link and search for the word sharp... and they review it quite well.

http://www.infotoday.com/online/OL19.../connolly.html

I have a sharp panel that I find is well designed... but there's something about the nviews that I like more... If only someone had a cheap nview z350 for me... hehe... not that I don't like my z210... but 1280 would be nice...

good luck

[cosmic023]

Hi All,

I received my Nobo OHP last week, but i did buy it as faulty hoping for a quick fix !

But the power supply transformer has burnt out, and since the unit is so old, they don't have a replacement !!

So i'll use the optics out of this OHP to build a diy projector

Does anyone know of any contacts, who could re-wind and refurbish the transformer in the UK ??

Otherwise I'll have to look for another OHP now, just to keep this project moving ??

Cheers

Cosmic023

[HanClinto]

Hi all! This site caught my eye at around 1:30 PM this previous Saturday afternoon, and it is now approximately 17 hours later at 5:30 AM on the adjacent Sunday morning. You guys write some great stuff, and have amazing ideas.

Anyway, enough with the kudos.

I sincerely apologize if this link has been posted before, but I thought it cool enough that I had to try and see if anyone else had done this before. The old LEDs that Vince was using were roughly $1.50 each at 9000 mcd with 20 deg of dispersal (right vocab? I'm less than 20 hrs into this so please bear with).

Someone earlier mentioned using LED car headlights... I wasn't able to find *headlights*, but tail/turnlights were available on one website in particular:

http://www.superbrightleds.com/cgi-b...gi?product=CAR

It has 12-LED arrays that are rated at 78,720 mcd with only a 12 degree viewing angle unit -- the smaller the angle the better it is for our projection purposes.

See their spec sheets here

A great part is, is that it uses a standard automobile 1156 or 1157 taillight receptacle -- available in any junkyard for next to nothing. Wouldn't be hard to buy an array of 12 or 20 of the receptacles.

The best part is the price! 12 LED array for only $6.99 US... that's about $0.59 per LED, and they're already arranged to accept 12 volt DC input.

By my calculations, to get 1,000,000 mcd (would that be 1,000 candle power?), it would take 12.5 of these... so an array of 18 or 20 should do the trick nicely. Granted, 20 of them would still cost around $150 US shipped, but does anyone think that this has feasability? If I only spent $50 on my LCD, I think I might be able to justify spending over $100 in LED's... if it was going to work.

What do you all think?

--Clint

[remp]

HanClinto

Its worth a shot. The leds seem cheap enough so if you just bought one assembly and tried it out should be good or no good.

What LCD are you thinking of for $50 ?