IR filter?? need some help

[tvard667]

Okay i was tearing apart a laptop happily ;D till i found there was no usable diode jus this weird crystal thingy any ideas? but anywasy i discoveverd that there seemed to be and and ir filter???? it was this rectangulare blue sheet of glass does any one know anything bout this???????

 

[tvard667]

okay now that i look at it a little closer i appears to have and orange sheen to it too kin of reflective but it was a 90deegree angle to the diode so how can it reflect up?

 

[Rhith]

I've seen things like this and I'm not sure exactly what the coating does but if you shine a laser though it you can get the beam to go through it and reflect off of it nicely. I have actually sued the reflection off of one of these to pop a balloon before.