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visibly opaque & IR Transparent

visibly opaque & IR Transparent

visibly opaque & IR Transparent

(OP)
Does anyone know of a visibly opaque polymer film with high IR transparency.

Or does anyone know of an additive to polyethylene that signficantly reduces visible transmission, without affecting the its IR transmission?

Thanks

RE: visibly opaque & IR Transparent

You could use what they use for sunglasses.

TTFN



RE: visibly opaque & IR Transparent

Most plastics absorb strongly in the I.R. spectrum. You have to be very specific as to what freaquency you want to pass and what you want to block.

RE: visibly opaque & IR Transparent

And, it depends greatly on what you're referring to when you use the term "infrared."  Various polycarbonates and acetates are quite transmissive in the NIR, e.g., between 0.8 um and 2 um, and there are plastics, such as those found covering thermal motion sensors that are relatively transmissive in the 8-12 um regime.

TTFN



RE: visibly opaque & IR Transparent

(OP)
Ideally, I would like the visible spectra (400 - 700 nm) to be opaque or around 20-30% transmissive. I'd like the IR transmission (2 - 13 microns) to be as high as possible (80 - 90% transmissive).

RE: visibly opaque & IR Transparent

And what ELSE do you want it to do?  Otherwise, I'm just going to recommend silicon.

TTFN



RE: visibly opaque & IR Transparent

(OP)
The material needs to be flexible, and provide a tight seal. We have been using polyethylene, but we want to block out the visible spectrum.

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