ir filter

[rikgrimsby]

hi there i need some help understanding ir filters. if a laser has a ir filter do i still have to wear saftey glasses or does the ir filter act as a "saftey glasses" ?

 

[Wratchet]

Yes you still need goggles, the IR filter just means the goggles don't have to filter IR as well.

 

[Ash]

if a laser has a ir filter do i still have to wear saftey glasses?

Absolutley. The IR is only a small percentage of the light being emitted from a DPSS laser. The reason it is harmful is because it is invisible, you have no blink reflex when it hits your eye.
In higher powered DPSS lasers (>5mW), the green will also do a great deal of damage to your vision if you are not protected with safety glasses.

 

[RoDnSuE]

You still need glasses designed for the wavelength(s) you need protection from.

Having an IR filtered laser just means the IR componant of the emitted light is filtered out, or at least reduced, depending on how good the IR filter actually is.

 

[rikgrimsby]

i see. thanks guys thats cleared that up

 

[icecruncher]

If you are looking at green, I just bought one of these.

One piece IR Filter - eBay (item 140442209584 end time Sep-17-10 07:39:15 PDT)

 

[bbshamsa]

Also, if you have any old webcams, or digicams lying around, you can disassemble them, get to the bit between the CCD and the lens, and you should find a small square piece of glass with a coating on it (sort of reddish/blue/green), and that's the IR filter.

If you remove it, you can place it over the aperture of your green laser and hey presto, you now have an IR filtered laser, AS WELL AS an infra-red capable camera/webcam.

you can then use the camera to see IR light.

Great for seeing how effective an IR filter really is, first-hand, as otherwise it's invisible.

I took one from an old 2.1 megapixel canon camera, and was surprised to see how bright the IR coming out of one of my greenies was, and how it completely disappeared once it was filtered.

 

[RoDnSuE]

I noticed the seller claims these are BG39. Is BG39 the best bang for the buck?
I'm thinking of ordering 4 of them.
Thanks,
Rod