IR Transparent Projection Screen?

AI Thread Summary
A transparent projection screen that allows infrared (IR) signals to pass through is needed for rear projection applications. Materials like frosted glass or plastic can work, as they transmit both visible light and IR signals. IR remotes typically operate around 780-820 nm, which means most screens that allow red light will also transmit this IR range. However, the discussion notes that some IR LEDs emit at approximately 950 nm, which may affect the choice of screen material. Samples from a specific manufacturer are being considered for testing.
Philmac
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Hello,

Is there such a thing as a projection screen that is transparent to IR? I need to project an image onto a screen (rear-projection), but I also need to send an IR signal through the screen from the side of the human user back to the side with the projector. I think there are metals/metalloids with this property, but those materials obviously don't make good projection screens. Any ideas?

Thanks,
Phil
 
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If you are rear projecting you need a transparent screen anyway - something like frosted glass or plastic

IR remotes are generally around 780-820nm so only 'slightly-infra' red, pretty much anything that transmits red light will also transmit theis level of IR
 
NobodySpecial said:
If you are rear projecting you need a transparent screen anyway - something like frosted glass or plastic

IR remotes are generally around 780-820nm so only 'slightly-infra' red, pretty much anything that transmits red light will also transmit theis level of IR

I have been informed that the wavelength emitted by the IR LEDs is approximately 950 nm. Does this change things? I would prefer not to let red through if possible.
 
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