A lot of people would like a longer throw with the standard triplet. It occurred to me that this might be possible with a slight redesign of the optics. The 10.6" lcd, combined with the standard fresnals makes it possible. That's because the standard fresnal is larger than the lcd. This means you can put the light source closer than the FL of the fresnal. Instead of having parralel collimated light, you would get converging collimated light. you can redesign the distance of the fresnal to lcd and lightsource to fresnal so that the light rays converge within the triplet. Keep the lcd to triplet at just the right distance for focus and you should be good to go. See pict.

Note in the pict that you only need one fresnal. You also end up concentrating the light from a larger area into the lcd. This should provide an overall brighter image. I don't know exactly what the throw would be. Someone smarter than me would have to calculate it out, but you could use either the 320mm fresnal or the 220mm fresnal for this.

I'm not that smart with optics, but if you are saying what i think you are saying that is awesome!! lol, i will keep an eye on this thread =P good luck.

You start with “A lot of people would like a longer throw with the standard triplet."

The light system you show does have a longer fl than a standard setup but I don't see how it will make the throw any longer.

The triplet always focuses on the LCD. So I call that value fixed. The triplet will always be 327mm fl. The read distance will be longer but the screen will determine that not the light system.

Any light system could be used and the "throw" will be the same.

Now you do have a long throw light system which might help if you had a really long FL triplet and could not find a matching Fresnel.

I was looking at the same idea back when I was using the larger lamps and giant reflectors.

The condenser lens now lets us adjust the rear fl fairly easy now.

The throw is determined by the FL of the triplet and the resulting distance it will be from the LCD. Changing the fresnels distance behind the LCD will have no effect on the throw.

DJ

Looks pretty interesting. What would be the distance between from the frensel to the lamp? Might work though.

Good Point DAZZZLA. Did not think of that. Moving the frensel will on have an effect on how well eand even the LCD is illuminated.

Even if it did work great,
you would loose the small form goodness by not cutting down the fresnel.

don't squish his dreams!! lol, let him try i wanna see!

I didn't say not to try it.

Maybe I'm mistaken, but I was under the impression the throw was dictated by the field fresnal. I thought the triplet FL dictated field of view and distance to lcd. I could well be wrong, though.

I'm not gonna try this. I still have a perfectly good working 15" lcd. I just thought that a lot of people were buying the 10.6", and already had the standard fresnals. This might be a good experiment.