How do you convert an LED infrared light source into visible light?

[Beachcomber]

Does anyone know what material(s) fluoresce under infrared light? For
those that are familiar with them, there are small plastic cards used
by TV technicians that will glow visibly when an infrared TV remote
control is pointed to a spot on the card in close proximity. I am
looking for the specific mineral or manufactured material that does
this.

I am aware that you can point these infrared controller sources at a
small inexpensive TV camera and more, likely than not, you will be
able to see the LED "light" in a video image of the signal.

Note that this is not the same as ultraviolet fluorescence, which, of
course, is much more common.

Beachcomber

 

[Al]

Does anyone know what material(s) fluoresce under infrared light? For
those that are familiar with them, there are small plastic cards used
by TV technicians that will glow visibly when an infrared TV remote
control is pointed to a spot on the card in close proximity. I am
looking for the specific mineral or manufactured material that does
this.

I am aware that you can point these infrared controller sources at a
small inexpensive TV camera and more, likely than not, you will be
able to see the LED "light" in a video image of the signal.

Note that this is not the same as ultraviolet fluorescence, which, of
course, is much more common.

Beachcomber

You might try the sci.optics newsgroup. They jaw about stuff like this
all the time. They are heavy on the science.

Al

 

[JohnR66]

Does anyone know what material(s) fluoresce under infrared light? For
those that are familiar with them, there are small plastic cards used
by TV technicians that will glow visibly when an infrared TV remote
control is pointed to a spot on the card in close proximity. I am
looking for the specific mineral or manufactured material that does
this.

I am aware that you can point these infrared controller sources at a
small inexpensive TV camera and more, likely than not, you will be
able to see the LED "light" in a video image of the signal.

Note that this is not the same as ultraviolet fluorescence, which, of
course, is much more common.

Beachcomber

Radio Shack used to sell a little card that would glow red when held in the
IR beam of a remote. Edmund scientific may sell this material now.
John

 

[John Gilmer]

Radio Shack used to sell a little card that would glow red when held in the
IR beam of a remote. Edmund scientific may sell this material now.
John

Didn't you have to "charge" the card first by exposing it to UV light?

The IR light would "trip" electrons/holes that were boosted to a higher
state and cause then to fall to some intermediate state and emitting a
photon in the visible light range.

 

[Beachcomber]

Didn't you have to "charge" the card first by exposing it to UV light?

The IR light would "trip" electrons/holes that were boosted to a higher
state and cause then to fall to some intermediate state and emitting a
photon in the visible light range.

No, I have one of the cards. It lights up pretty much instantly when
exposed to infrared light (such as from a remote control). It tells
the technician that the IR diode is producing at least some IR energy.

Maybe you are thinking of those glow in the dark devices or coating
materials, which, as far as I know, charge up under visible light.

I've never seen one of these that worked well (stayed on and glowing
all night after a full charge). When I was a kid, radioactive Radium
glow-in-the-dark watches were common. They would glow in complete
darkness but they supposedly killed a lot of workers in the
manufacturing plant.

What I am looking for is the mineral or rare-earch material that will
light up in the presence of infrared. Something commonly available
would be nice, but it seems to be a trade secret.

Beachcomber