My 19" LCD Projector

[gssmind]

Greetings,

First of all I am new to the forum and this is my first post here.

I am an absolute new bee to DIY Projector world however, am absolutely inspired and devoted to building a projector.

Doing some research I find that there has not been an attempt made to make one out of a 19" LCD or higher size LCD in general. So I am going to make an attempt to make out of my DELL 1905 LCD. Haven't even orderd the parts yet as I am still doing research and am looking for some input on what issues I may run into.

Disappointed with no find on any attempt to 19" LCD was definitely re-inspeired by looking at this post at diyAudio.com

My 17" Projector

So for the moment I have just one ingredient of the many, my DELL 19" LCD that measures exactly 12 H x 15 W.

I am looking for a suggestions and issues for suitable options I have available for projector designs, Fresnel lens size, you know the rest.

[germax]

I am not sure that I understand why would anyone want 19" LCD projector.
You are pushing it with the lenses, size will be enourmous
and worst of all projected image will huge.
How close to the sceen will it have to be?

I have 15" and long throw lense and I'll have to reduce size
of the image to make it fit on my screen, and I bought biggest screen
that would fit in the room.

Beside that resolution of 17" and 19" is the same...

Am I missing something ?

[tgreenwood]

If you are determined to use a 19 inch LCD here are the calculations that I came up with.....

For a 100 inch diagonal image (more than 8 feet)
You would have to use a 22 inch focal length opaque projector lens and have the projector a little more than 11 and 1/2 feet away from your screen. I hope that you have the room for it.

There's a 22 inch opaque projector lens on Ebay right now
Opaque Projector Lens and they have become kind of rare, I'd snag it now if I were you.

Tgreenwood

[bokinator]

hhmm
how do you know it's a 22" focal length lense?


i'm sorta new to this whole projector business.

[Mikey p]

Click on the pics and it says 22" E.F.L.

[gssmind]

Greetings,

First of all I would like to thank everyone for getting me started with some questions/feedback/suggestions. I will try to answer any questions and will also ask a few stupid questions along the way as I learn more.

Here are my intentions:

1. Build a projector from a 19" - Why?
1. Well frankly I am exited to build this one and get a good understanding behind how the entire thing works. Want to know the physics/optics behind it as this is my first one. I am all about getting a nice crisp image. So the higher the resolution the sharper the image, and day-by-day the new LCD's are going higher up in the resolution and fairly smaller in size. However, the final goal later is to take a monitor with either 1600x1200 or 1920x1200 and build a projector from it. So if I can find a LCD of a smaller size that supports this resolution, I am a happy camper.

2. Without any know-how I just assumed the following:
2. We have the following sources of construction available:

a. Light source of 400W available - I think this is more then enough for a good nice bright source of light.
b. Wood, Wiring, any other construction material is available.
c. Two challenges are going to be: Focal Length Lens and Fensel Lenses. Also Fensel Lenses can be found of a bigger size so the real challenge will be the Focal Length Lens.

3. Thank You "tgreenwood" for pointing my attention to the EBay auction for the 22" inch Focal Length Lens. I am bidding on it right now

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Last but now least, I started to get the basics out of the way so I ripped apart my Dell 1905FP LCD and boy that puppy is hard to rip apart, I had to manually cut it. I will have pictures posted soon.

Haven’t completed it all but I just took out the back plastic black frame. Had planned to take the LCD and build a nice frame but spent all my spare time yesterday just ripping apart the back frame. I took some pictures, will post them soon. But will take the LCD out and take the exact size and build a frame from 3/4" MDF Will definitely take pictures and keep you guys posted.
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[Mikey p]

As far as the 22 inch lens goes, I've never seen any results that show that lens has a big enough field of view to cover a 19 inch lcd. It has been shown to work with a 17 inch lcd however. Maybe it will work with a 19 inch lcd. You'll be the first to find out as far as I know. Bottom line is you're taking a chance on this.

[gssmind]

Hey Mikey p,

Yeah I kinda got that feeling when I decided to do this with a 19" aswell. But The link above I have shows calculation/speculation that it could have worked with a 19". We will find out.

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Question 1
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I was wondering if any of the lenses below are any good to me:

http://search.ebay.com/projector-len...sPageNameZWLRS

Any suggestions ?

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Question 2
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Am I good-to-go on getting the following Frensel Lenses:

330mm Back Fresnel
550mm Field Fresnel

Any suggestions ?

Thanks in advance.

[Mikey p]

The only lens that might work in that list is the one you're bidding on. A 650mm fresnel is a better match for the 22 inch Besseler lens. A 330mm back fresnel would be good if you also want to use a precondenser lens. I suggest to go to http://www.lumenlab.com/ and sign up if you're not already a member. ( it's free) They have a focal length calculator and precondenser tool that you'll need to figure things out. They are also the only place I'm aware of that have lenses that can handle 19 inch widescreen. (I'm not sure what your Dell is, 16x9 or 4x3)

[germax]

Bigger the LCD more difficult it is to get sharp image
on the center and on the corners at the same time.
And that is true even for 15". 19" you will definitely
have problems getting everything in focus.
If you are even lucky that your lense covers all of it.

I guess you can always use just portion of your LCD
that you lense can clearly see in the worst case...

Originally posted by gssmind
Greetings,

Here are my intentions:

1. Build a projector from a 19" - Why?
1. Well frankly I am exited to build this one and get a good understanding behind how the entire thing works. Want to know the physics/optics behind it as this is my first one. I am all about getting a nice crisp image. So the higher the resolution the sharper the image, and day-by-day the new LCD's are going higher up in the resolution and fairly smaller in size. However, the final goal later is to take a monitor with either 1600x1200 or 1920x1200 and build a projector from it. So if I can find a LCD of a smaller size that supports this resolution, I am a happy camper.

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