My ProView 15.4" 1280x800 HD project...

[doublethink]

greetings! I also want to use the same LCD to make a homemade LCD.

I have been doing lots of reading, I have some questions for you.

Dont you think it would be optimal to build a rectangular enclosue to maximaize light output?

And therefore wouldnt it be a better idea to use 16:9 widescreen lenses from http://www.diyprojectorcompany.com/c...products_id=40

but choose the 16:9 option?

any idea how big those lenses actually are?

Also why are you so concerned with bouncing the light all over the place, is space an issue for you?

look at this thread for images of doom3 at 110 inches of amazing colors:

http://www.lumenlab.com/forums/index...pic=1576&st=40

(down towards the bottom)

thats basically why i want to do this, and for movies. TV is mostly an afterthought, but probably will happen to.

Thanks for your time, I can't wait to start mine!

[Hezz]

Inkog,

Nice project you've got underway. By the way the narrow viewing angle you mention about this LCD in one of your earlier posts is an advantage for a DIY projector as less of the light output is dissipated at angles which will not strike the objective.

A narrow viewing angle is actually what we want for this application.

Hezz

[Inkog]

doublethink,

For this LCD, the only fresnels I've found (at least currently available) are the 15.5x15.5" from DIYprojectorCompany. I plan to cut my down to fit this LCD. Even if the 16:9 fresnels they have would match the size of this LCD, it is not 16:9.

As far as folding the light in that first drawing I made, I was hoping to make the smallest enclosure possible. I have now figured out that it will be impossible to fold the light on the light engine side due to the 330mm fl of the fresnels available paired with the size of this LCD. Basically the FL is too short and the lightbox would get in the way.

I have seen Sepultura PJ and it is very impressive. I can't wait to play Doom 3 at 110" @ 1280x800

Hezz,

I thought that would be the case, this proview keeps getting better


As for this drawing below...

Fig 1. I figure I'll be loosing 42.78% of the "good" light coming from the light engine. Are there any non-circular pre-condensers that would improve this?

Fig 2. My proof I can't fold the light before the LCD with this LCD without a much longer fresnel FL. I also belive the longer the frenel FL the less usable light is collected from your engine. Can anyone confirm this?

Fig 3. Pretty much the setup I'm looking into now. I just need to find a pre-condenser lens close to 100mm dia. and 100mm fl. This should give me ~30% good light from my engine. Maybe a 80mm with a <80mm fl would be better I'll have to draw that out....

30% - 43% (from fig 1) = 17.1% Damn these things are inefficient

Well back to the drawing board...

[Squeeky]

Let me know what you find, cause I've been looking for a PCX lens with a 100mm dai for awhile. I did find a DCX with 100mmx200mm FL thats the closest. If you find anything let me know, cause I'm planning on building my next projo based off this LCD.

Thanks
Squeeky

[Hezz]

Inkog,

The ineffeciency of the system is real which is why we have to use a 15,000 - 20,000 lumen light. The LCD itself is rather ineffecient also.

Keep up the good work. I am planning on building a double parabolic reflector with the same aspect ratio as the LCD but this is going to be one of the hardest things to build on my projector.

I will be collimating the light and using only one fresnel but this of course requires the projector to be larger in size.

I think I am going to use this Proview LCD as I can't afford the 1980 x 1200 LCD controller combination that I had envisioned.

Hezz

[Squeeky]

Ok I did some searching for PCX lens. The following is the closest I have found for the requirements you requested. Keep in mind these are expensive

PCX dia 100mm fl 120mm $129

PCX dia 109mm fl 150mm $89

The best I have found though in range of FL is that with a 60mm dia. Although I think that will be too small, but FL range from 90-150mm


Let me know what else you find....

[Squeeky]

Did some more searching. Found some heat resistant. Not sure how much heat they can resist though. Price wise isn't too bad

Dia. FL. Price
114.3 165 $66
114.3 190 $67

Another Link here. doesn't list specs but replacement lenses for projectors
Link

[Squeeky]

Last post I promise, did some more searching:

No prices but has perfect size!

Every condenser you would ever want!

[Inkog]

Squeeky you are the man! (woman?, mouse? )

the AOI177 from AlignOptics looks very nice if my maths are correct.
100mm ASPH 77.8mm fl

I think I was a little too conservative on estimating the usable light from a 100mm 100mm fl lens would produce on my last drawing. Instead of ~30% I think it would be more like 47-52%. I think this 78mm fl would produce more like 55-60% perfectly usable light.

Remember this is with the perfect spherical reflector in place. I have yet to find these either Anyone got a good source on these?

I also think this setup would still give plenty of room for cooling and may just allow for a small hot mirror to be placed before the condenser lens to help with IR. I'll draw up my ideas for the light box tonight.

I called AlignOptics but they were already closed for the day. I'll try again tomorrow.

Thanks again

[Squeeky]

I'm in the same boat we can work together on this. I'm planning on using:

IKEA napkin reflector, s400dd, condenser (what we find), 220mm 15.5 fresnel, proview, 15.5 330mm fresnel, and standard triplet.

other reflectors that look nice
Mirror

Napkin holder

I do not have an ikea near me though!

Inkog, if you would like AIM me Squeeky4711 or PM me here I think if we put our heads together we can build an awesome HDTV projo.