I'm wondering if I can find a cheaper source of ND filters that work in the near infra-red (out to ~800nm.) We have been using Kodak Wratten Gel filters. (ND 0.70) We originally purchased large sheets, but they now come in only smaller (and more expensive) sizes. I looked into the Lee ND filters (polyester) But these don't block light out past ~700nm. Any other sources would be appreciated.
For what it's worth, the use case here is to attenuate a diode laser beam, without disturbing the polarization; the laser can be tuned from ~770-795 nm.