Is there some supplier of optical glass that I need to contact if I want to mount a pj behind a wall? I don't want a hole in the wall. I want to cut a square hole and mount the pj behind it but want to cover the hole with glass to keep out sound. I'm sure I can't just use window glass.

Any suggestions?

Edmunds Optics has good float glass:

http://www.edmundoptics.com/onlinecatalog/DisplayProduct.cfm?productid=1919

The Anti Reflective coated windows help to keep reflected light from going back to the projector lense. Make sure you mount the lense at a slight angle for this as well.

I've used these. Pretty good at limiting reflections.

Edmunds Optics (http://www.edmundoptics.com/onlinecatalog/DisplayProduct.cfm?productid=1919)


Edit: Kraig beat me to it.

air has the least reflections :)

Recessed lighting flanges offer very clean installs for a few bucks. Home Depot will have dozens to choose from

http://www.lightinguniverse.com/products/default.aspx?tid=330

Make sure you mount the lense at a slight angle for this as well.

Do you mean mount the glass at an angle? And if so, should it be out at the top (away from pj)

Do you mean mount the glass at an angle? And if so, should it be out at the top (away from pj)

Frankly I don't think it matters because your just making sure that light doesn't reflect back to the pj lense. I always angled the bottom out. I glued the glass to the box with silicone and did a thicker bead at the bottom to get the angle.

There is a such thing as projection glass which is used in commercial theaters and screening rooms. It has nothing to do with reflections. Standard glass has a slight green tint. Projection glass is water white. The stuff is not cheap but still affordable for an HT project.

There is a such thing as projection glass which is used in commercial theaters and screening rooms. It has nothing to do with reflections. Standard glass has a slight green tint. Projection glass is water white. The stuff is not cheap but still affordable for an HT project.

Do you have a link?

Mitch,

Don't bother hunting. The Edmunds glass is the same thing glimmie is talking about. Look at the specs - 96-99% transmission which is about as clear as you get without spending a fortune. It does not have a green tint I assure you..

I have worked on several higher and lower end recording studios. generally for maximum reflection elimination you want a 45 degree angle involved.

Between sound proof rooms, we would make a double pane glass window where one of the panes would be at a 45 degree angle to the other.

With otical glass, I am not real sure if this would matter. You would probably want water white glass. But I am not so sure how much any optiocal glass would or could tint the light flowing through it. Not much in all honesty, flase color is usually added in optical elements that have various refractive indexes, well the light here is passing straight through at zero telextention or reduction. In other words unity gain. :)

I've done quite a few HT installs and never came across this request though. I'd say if there is a canned product for this, I'd buy it and only DYI install the solution, not fabricate it.