These solutions seem to be what I'm looking for:
http://www.thorlabs.de/newgrouppage9.cfm?objectgroup_ID=7541
http://www.autospeed.com/cms/article.html?&title=Building-a-High-Performance-LED-Lighting-System-Part-2&A=109715
http://www.mightexsystems.com/family_info.php?cPath=&categories_id=225...
Hmm, the Idea is that the light beam becomes clearly visible when it hits the side of the tank and continues as a visible cylinder until it hits a surface.
Hello!
As this is my first post - I'm Mike from Poland, currently studying product design on Academy of Fine Arts in Warsaw.
I'm working on a sculpture - light installation.
I want to achieve an effect of a regular beam of white light - light cylinder in slightly opaque water. Sort of similar...