- Nov 5, 2007
It looks like he's shining the laser through sunglasses(I guess, cause those do a good job at filtering UV and violet) and onto a piece of paper.Benm said:How did you make those shots? Did you point the laser through the glasses onto a wall and took a picture, or did you point the laser onto a wall and took a picture through the goggles?
Benm said:I am actually very surprised if you can see the dot on a wall like that when shining the laser through goggles, sunglasses or any other filter. It is quite normal for such filters to fluoresce when it by UV light, but that would not result in a collimated beam coming out the other side.
All in all its a very puzzling effect, though i'm quite convinced the diode cannot be lasing at both wavelengths at the same time. But if its emission from impurities in the diode junction it is very surpising that it can be focussed across a room like that.
That would be it then, just emission at unwanted wavelengths similar to what occurs in blue leds. Still interesting that it's that noticeable, and i guess the amount and color of this phenomenon varies a lot between diodes.Ace82 said:I agree. I just tried that with my blu-ray and goggles, it does create aN orangish light, but is not collimated. Despite how dim dot is, it expands like a well focused LED would.