Here is how to spot IR leakage from green lasers

[Phazonx]

A nice simple way to find IR leakage is to block out everything else right?

Watch my video.

 

[Things]

Re: Here is how to spot IR leakage from green lase

Yep, i found that shining a green laser through a peice of red perspex blocks most of the green, and if you get a camera on the other side, it will have white/bluish colour around it if it's leaking ir

 

[Benm]

Re: Here is how to spot IR leakage from green lase

It's a nice way to detect if there is -any- infrared present. However, there is no way to quantify the information from the camera display. It's not possible to tell if that little spot has, for example, 1 or 100 mW of IR light unless you know more about the IR characteristics of the camera.

 

[mikeeey]

Re: Here is how to spot IR leakage from green lase

now you say we would need an infrared compatible camera, my phone camera can pick up near infrared from a TV remote, does that work? or does it need to pick up more than just near infrared?

 

[Phazonx]

Re: Here is how to spot IR leakage from green lase

I'm not sure if it will work. :-/

 

[Benm]

Re: Here is how to spot IR leakage from green lase

If it sees a remote control's led, it will probably work. Remote controls usually work in the near IR, 850 nm or so.

 

[pseudonomen137]

Re: Here is how to spot IR leakage from green lase

IIRC, remote control leds are ~940nm so it should be able to detect the 808nm pretty well. With a lot of cameras though, you'll need to remove the IR filtering for better results. Some videocams have "nightshot" and other things that remove the IR filtering (if present).

For removing green, a great tip from the LC was to try using red wine. You may need to hunt down the right type, but in general shining a greenie through a glass of it will cause the green to be absorbed, and much of the IR will pass. For those under 21 , perhaps some sort of red juice, and you can also use film negatives as crude green block/IR pass filters - just stack unneeded negatives a couple layers thick.

 

[Phazonx]

Re: Here is how to spot IR leakage from green lase

...and you can also use film negatives as crude green block/IR pass filters - just stack unneeded negatives a couple layers thick.

:-?

Um, yeah, thats what I just did in the video.

 

[Ref]

Re: Here is how to spot IR leakage from green lase

http://www.edmundoptics.com/onlinecatalog/displayproduct.cfm?productID=1613&search=1

$50, though.

 

[Cyparagon]

Re: Here is how to spot IR leakage from green lase

Why hasn't the most basic concept in optics been mentioned? Why not use a prism?

 

[BlueFusion]

Re: Here is how to spot IR leakage from green lase

Thats a rather good idea. But you'd have to bung the prism really close to the laser cos the IR is so divergent.
But that could work. You'd get a green dot and like 10cm left or right, an IR blob.

 

[Switch]

Re: Here is how to spot IR leakage from green lase

Thats a rather good idea. But you'd have to bung the prism really close to the laser cos the IR is so divergent.
But that could work. You'd get a green dot and like 10cm left or right, an IR blob.

The IR dot in the video wasn't that divergent.I think a prism might work pretty well

 

[Deny_Defy_Hi]

Re: Here is how to spot IR leakage from green lase

If it sees a remote control's led, it will probably work. Remote controls usually work in the near IR, 850 nm or so.

so that means you shouldnt point a remote tv control next to your eye?

 

[FireMyLaser]

Re: Here is how to spot IR leakage from green lase

Of course not  ;D