This may get weird, so I'm hoping I'm explaining this as clear as possible. I'm looking for a way to evenly distribute multiple light sources over a medium, much like (exactly like) the backlighting in an LCD panel. HOWEVER- I'm looking to keep the light going in one direction only and have the whole set up transparent (or tinted is fine, but mostly transparent) I've only been able to fix the "one direction" of the problem, but I can't seem to get how to get the light evenly distributed with little or no hot spots. All the methods involve a diffuser film, but that isn't transparent, rather it's translucent. I was thinking on the lines of using the properties of polarized light, by bouncing the light between two spaced panels until it escapes, but I'm not too sure on how to achieve that. I'm probably going to have another one or two questions, but that's for later. For ANY help, I thank you.
If I understand your request rightly... You could try using a laser scanner to bounce the light backwards and forwards across the surface you wish to illuminate. Although it would really help to see a picture of your set up as I'm not really sure what it is you're trying to create here. It sounds to me like you're trying to create a back lit picture frame but I'm not really sure.
I'm trying my best to not let people know what it is, so that's my issue. I'd do the laser scanner, but it has to be small, and preferably with nothing in front of the top layer.
I'm not sure how you're going to get an even backlighting from only one side as all lights diverge from the aperture, even lasers. What that means is that the brightness point will always be where measurable divergence is at its lowest, which in the case of things like LEDs is at the tip of the bulb, like this (=-<). If its absolutely imperative that your light source must be on one side, you might want to consider using an optical focusing ring to focus the light so that the lowest point of divergence is in the center of your project, like this (=>-<), instead of the aperture. Although I have to admit that is complicating matters greatly. Unless you use some sort of transparency gradient on the surface I don't really know what you can do. Sorry I can't really help you further without knowing the specifics of what it is your building, all I can say is that it will be extremely difficult to achieve what it is you want to achieve. Assuming you don't mind which wavelength of light you use I'd highly reccomend building an XY laser scanner and have it scan across the inside of the surface you wish to illuminate. Depending on the speed of the motors the laser will scan so fast that it shouldn't be detectable to the human eye and having control over the XY axis will allow you do all sorts of crazy things, not just illuminate a surface. I really don't know what else to suggest. Having the light source on one side only is seriously limiting your options. Again I don't really know what you're building so it just makes it harder for me. I'm assuming you're building some kind of wall mounted light fixture or a modded PC case or something.
Yeah, I thought this was going to be hard. As before I'd do a light source that sweeps over it at speeds fast enough to become virtually invisible, but it's small enough that that's out of the question. Hmmmmm.... Maybe I'll just try and do some soft lighting on the sides and see how it looks. Any other help is good, though!
Try reading up on the Brewster's Angle, you could have a Fresnel reflector custom made that uses this, in fact that is how some compact backlight assemblies work, The Gameboy Advance SP also uses it.
So can you give me some clues as to what you're building? Are you modding a hand held to be back kit or something? I've got no reference to go on so don't really know what to suggest to you, but I'm a massive light nerd so your project intrigues me! I'll look forward to seeing what it is you're doing if you ever decide to show it off, it sounds like quite an intricate project.
Arg... I'd like to give some info on this project but that's the point of it- I can't release any info on it... key point here is that it must be see-though. Oh, and if you meant you're glad physics class didn't make my eyes glaze over, I actually had fun in physics class. Sometimes it's fun to be mind-fucked when you learn about things like special relativity...