[ChrisM]

I am experimenting with a long wavelength IR sensor (5,000 - 14,000 nm), and am looking for some material to protect the sensor when I install it outside. Apparently most common materials (glass & plastics) do not transmit LWIR. I have not tried the dark-coloured material used on security camera housings, but expect that it wouldn't work, since these cameras use NIR (700 - 1100 nm).

Does anyone have any ideas?

Cheers
Chris