Is it possible to see an infrared light by pointing the device (a remote control) at a mirror?

Well, lets assume a mirror can reflect infrared light.

 

A mirrow reflects light that is shined upon it, so what goes in will be pretty much the same as what comes back out. If you can't see the infrared light going in, will you be able to see the infrared light coming out?

If the question means can mirrors reflect IR, the answer is yes. Depending on the wavelength and mirror type you may need a special coating on the mirror to do so with high efficiency. Dielectric mirrors in my lab are coated for broadband NIR, basically from 700 - 1000 nm, for reflectivity >95% or so. We also have some gold mirrors that reflect reasonable well in that range.

 

UV, on the other hand, is a lot tougher to do with high reflectivity.

 

 

As gonelli points out, though, it won't make the invisible visible.

if you want to see ir light take the red filter off the lenses of a camera and than you can see it.

if you want to see ir light take the red filter off the lenses of a camera and than you can see it.

 

YT has discussed this somewhere, and I've done it, with a webcam. Many CCD viewfinders also lack an IR filter, allowing you to detect IR which doesn't end up in the picture. Some cellphone cameras have poor filters, too.