Flir Macro Lens Version 2
Two parts required:
Lots of very clever people have put together the Flir E4 camera with a macro lens based on laser cutting lenses. For example: mike's electric stuff
This design avoids modifying the hardware, by having a friction mounted macro lens. These two parts are designed to fit the Flir E4 - E8 range cameras.
You will also require: a lens:
ZnSe 20mm Lenses such as: these ones on ebay
have been shown to work well (update: US buyers have used: : this seller
If you don't want to buy the lens securing part, just use a tiny blob of blue-tack, hot-melt or a paper wedge to secure the lens. Ensure that these substances don't attack the surface finish of your lens though!