Considerations for buying IR filters?

[mhakali]

Hello!

I am looking for an IR filter to get a proper 532nm reading on my LaserBee.

I see that a lot of generic camera lens filters are available on E-bay. And they seem to be tuned to a specific wavelength of IR blocking.

Now however the possible emitting IR lights from a green laser is obviously 808nm and 1064nm.

Should I take any considerations when buying an IR filter due to this? Do you have any good recommendations?

I don't care about the filter size. It may be a full camera lens filter. But it should block as much as possible of the relevant 808 & 1064nm wavelengths and as little of the 532nm as possible for a correct reading (obviously...).

Mikael

 

[HIMNL9]

Well, for this use, i think that any AR coated anti-IR filter will be good ..... probably, the most important thing is just the AR coating (less reflection = less loss in passing light, usually)

Also, a non-colored one, ofcourse


Edit: just as example (this block also UV)

http://cgi.ebay.com/Leica-UV-IR-39m...ters?hash=item20ad4c7bea&_trksid=p3286.c0.m14

 

[mhakali]

Well, for this use, i think that any AR coated anti-IR filter will be good ..... probably, the most important thing is just the AR coating (less reflection = less loss in passing light, usually)

Also, a non-colored one, ofcourse


Edit: just as example (this block also UV)

Leica UV/IR 39mm filter Black Brand New - eBay (item 140346424298 end time Sep-23-09 04:48:31 PDT)

Thanks for the tip! I'll continue my research!

I found these thingies:

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=130328396104

But I don't first of all need 10 of them. And it'd be preferable for a bigger area that's easier to handle

Those ones above seems to be spot on 808 + 1064nm however.

Mikael

 

[HIMNL9]

4x4 mm are small ..... probably these are the ones that are glued on filtered green modules.

For large area, probably the better solutions are still photographic, otherwise need to ask some manufacturers for specific products.

just as example: Products List, ROCOES

Looking in the hot mirrors / IR cut section, the UVIRCUTAR-385/725, as example, looks almost perfect, at least seeing the graph

(now just need to know the prices )

 

[ElektroFreak]

I recommend AR coated BG-38 or BG-39 filters. They are the industry standard IR filter, and they allow .01% of IR to pass. BG-38 or -39 is used in all IR filtered lasers unless they have specially coated output couplers.