Can you say which iPhone? I own a 3G and the 4 (not S) and Im pretty sure none of them has an IR filter...
Good luck with your laser...
If you want to start building lasers, start with red, blue or bluray ones... Greens are DPSS (yeah, there is this one diode, but I think this is out of range with 250$) and this is a lot more complicated. Actually most here are using finished modules for their green builds
[edit]
Wow, looks like its true, the iPhone 4s does have an IR filter. Im sorry Iman, looks like this time you were right.