I've been thinking of making a simple projector by using a Light Source ---> LCD panel ----> Projector Lens. I've been looking for some rear projector lenses like the Delta IV mentioned in another website, but I've only found a Fujinon 4 1/4 inch lens. I'd rather use a 5" LCD as is has a higher pixel count as compared to the 4" LCDs I've seen. But that Fujinon lens is 3/4 inch small then the LCD and would cut off just way too much.
My question to those who use lenses is, can you place the panel abit away from the lens to allow the entire image to be seen, or must the panel be right up against the lens assembly? I know its not the same for all, but I'd like to know how it is with your setup.
Also, if anyone knows where I can get some large projection lens assemblies like the large Delta lenses, that would work alot better (and be simpler) for me, or even higher resolution 4" LCD panels.
My question to those who use lenses is, can you place the panel abit away from the lens to allow the entire image to be seen, or must the panel be right up against the lens assembly? I know its not the same for all, but I'd like to know how it is with your setup.
Also, if anyone knows where I can get some large projection lens assemblies like the large Delta lenses, that would work alot better (and be simpler) for me, or even higher resolution 4" LCD panels.
your right in that most of these lenses are designed for curved CRTs. However the fujinon 4-1/2" from surplus shed is definitely for a flat CRT, as I have used it sucessfully with a 5" LCD. In order to not cut off any of the viewable image however you must converge the light strongly through the lcd which is not optimum for a few reasons. I use 2 fresnel lenses on the light source side to converge the light.
Thats the method I was thinking of using. I have 2 large fresnal lenses doing nothing but gathering dust here. I figured 1 fresnal behind the lcd to converge the light some, then another infront to get the image to the rear lens of the Fujinon. But I wasn't sure if that would work at all. I'm not sure if I'll go ahead with plans I was going to use since the light output is very poor, so I may just go the simple way of a OHP and display that plugs right into the video card. At least that way the image quality sould be higher then with a 5" LCD. I've checked the OHP thread though and it only has like 2 replies/reviews of OHP. I'd rather not buy a OHP without being sure its a good one and wont cost me an arm and a leg to feed (bulbs).
Would you have any pics of the setup with the Fujinon lens or any other info MuzzMan?
Would you have any pics of the setup with the Fujinon lens or any other info MuzzMan?
You'll find some pics in the small lcd thread. My setup is still very experimental, and actually I was a bit disappointed with the brightness of the image I got from my first go with the fujinon. It is definitely less efficient than what I had before, which was same light source and lcd, but a ohp fresnel used for the projection lens. The image quality is better now, but the image is dimmer for some reason. I can only think that the angle through the LCD is a lot more than what it was, so the LCD is blocking more light than it used to. You could be on to something with one fresnel before the lcd and one afterward, but I don't know if that will work, because the fujinon needs to be very close to the lcd to function. I can't easily try it because stuff gets in the way when you try to mount a huge fresnel close to the lcd.
Definitely safer to use ohp and ready built lcd if you are just after the result and don't want the pain and glory of complete diy
Definitely safer to use ohp and ready built lcd if you are just after the result and don't want the pain and glory of complete diy
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