My ProView 15.4" 1280x800 HD project...

My ProView 15.4" 1280x800 HD project...

Hello all,

Here goes my first attempt at DIY Projection... I'm going to attempt to detail my trials and tribulations, here in this thread, so you may all learn from my mistakes (But mostly so I can get some good help and answers to my many, many questions). I'm going to try and do my best to post pictures and sketches as they come.

After many weeks of researching I finally decided to go with the 15.4" ProView PL576ws 1280x800 widescreen LCD of which I picked up at my local Staples for 243.78 after taxes. HD was a must for me and this is the best LCD I could find at this size and price point.

LCD Details:

1280x800 native
0.259mm Dot pitch
332*208mm display area
OSD option to keep aspect ratio of smaller than native resolutions without stretching. Supports these resolutions:
640x480
720x400
800x600
1024x768
1280x768
1280x800

(Please offer your comments and suggestions on the following)

I think I’m going to use the 15.5x15.5 330mm rf fresnels and the 135mm Long-Throw Projection Lens Triplet from DIYProjectorCompany.

I’m pretty sure I’m going to go with the 400w MH MQI setup. I’m just not sure if I should go with DIYPC’s 4200k setup as I understand ~5100K is best.

Below you’ll see a sketch of the dual fold design I’m toying with now. When measuring focal length when folding light would you measure the distance represented by the red lines like I’m guessing?

Some pic of the monitor

Another

One more

TaskMaster said:

Do you see any lines in the picture like Ben_tech mentions in this thread ?

Click to expand...

Nope I have no problems with my panel at all. No dead or stuck pixels or anything like Ben_tech describes. Other than the poor viewing angle and some minor backlight bleeding near the bottom of the display, I would say it is just as good as many much higher priced LCDs out there. IMHO, the LCD itself has very good colors and a good response time.


I should mention that the pics above are 720p content from my ATI HDTV Wonder card.

Squalish said:

I find it unlikely that you're going to find a cold mirror anywhere near large enough to work, at a price anywhere near practicality.

I found some nice 6"-8" Rosco hot mirrors at B+H photo which I will probably be using, but those are gonna run me $60-$130. Large dichroics are REALLY expensive. Hot mirrors have an advantage that you can stick 'em right in the main beam near the bulb where it's still small.

Click to expand...

Unfortunately, you seem to be right. I have contacted several places, and the ones I have found are <6" & >80$, nowhere near practicality. I think I have found a supplier for 3mm 15.5x15.5" clear tempered glass with a 80% IR coating that the manufacturer thinks can handle a 96% UV coating on the back side (possible heat issue). I'm still waiting on a call back for verification and pricing from an engineer.

I also found some UV blocking fresnels but they are too expensive for my budget. From my research, acrylic fresnels should be inherently partially UV blocking anyway.

I think I may steer clear of a dual fold and go for a standup design with one front surface mirror. I’ve seen some nice fully adjustable designs like this, which have good keystone and focusing.

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 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