Because there are so many infrared LEDs for security cameras, Why is there not a fluorescent infrared variety for illuminating dark areas for cameras? There are many different types of phosphors, so this should be possible. I was thinking of making a high power 50 watt LED infrared illuminator cooled by an old CPU Cooler.

The efficiency of the light conversion will be very low: In best case one UV photon (coming from the mercury discharge) generates one photon of the desired wavelength. But the point is, the UV photon has energy around 5eV (just rough order; haven't calculated that), the IR photon caries around 1eV.
That means about 80% energy losses just by the photon conversion, that is way too much for a practical use.

The LED's alone are not super efficient (compare to e.g. the blue LED), but because they do not need any conversion, the overall output is not that bad.

And for high power use there I've seen special HID's (it was with the security cameras on the fence around NATO in Brussels; just on the main street; but it was in 2006, I do not know, whether it wasn't upgraded to something else since that time), where the active has makes sure the discharge generates directly the desired IR.


But with high intensity IR there is quite important safety problem: It does not trigger the eye iris to close, but it still get focused by the eye lens and carries quite significant amount of heat, so with not well designed installation there is a risk of eye damage.
Of course, diffused source (fluorescent style) won't pose that problem.

The efficiency of the light conversion will be very low: In best case one UV photon (coming from the mercury discharge) generates one photon of the desired wavelength. But the point is, the UV photon has energy around 5eV (just rough order; haven't calculated that), the IR photon caries around 1eV.
That means about 80% energy losses just by the photon conversion, that is way too much for a practical use.

The LED's alone are not super efficient (compare to e.g. the blue LED), but because they do not need any conversion, the overall output is not that bad.

And for high power use there I've seen special HID's (it was with the security cameras on the fence around NATO in Brussels; just on the main street; but it was in 2006, I do not know, whether it wasn't upgraded to something else since that time), where the active has makes sure the discharge generates directly the desired IR.


But with high intensity IR there is quite important safety problem: It does not trigger the eye iris to close, but it still get focused by the eye lens and carries quite significant amount of heat, so with not well designed installation there is a risk of eye damage.
Of course, diffused source (fluorescent style) won't pose that problem.

Now we just need high power diffused infrared LED tubes. Is there any place to get those special HIDs?

For the LED's: Buy a lot of 100 or so of IR LED's and assemble it yourself (on ebay it is not that much expensive, but do not exceed 50mW/LED and place them onto the board at least 1cm apart each other).

The HID I do not know, it could well be even a classified equipment, so not accessible for "mortals" (I've not seen it anywhere else except that NATO property in Brussel)...

A while back i was looking to make IR LED illuminator for CCTV. There were 20W COB LED modules on Ebay. its power density is quite high, but i guess you can diffuse it by putting the LED into any prismatic GLS luminaire..

What type of HID lamps were used there for the IR ? Were the lamps filtered (woods glass) or plain arctubes ?

A while back i was looking to make IR LED illuminator for CCTV. There were 20W COB LED modules on Ebay. its power density is quite high, but i guess you can diffuse it by putting the LED into any prismatic GLS luminaire..

What type of HID lamps were used there for the IR ? Were the lamps filtered (woods glass) or plain arctubes ?

I would think that Wood's Glass is for blacklight.
The high intensity infrared could be useful for deterring thieves.

Woods glass is fairly transparent to IR as well as UV

Usually ruby red glass is used for IR lamps rather than wood glass.

Actually, How hard is it to make your own infrared HID at home?

One of my portable HID lights has an IR filter.The Woods glass.Other portable HID lights have IR filters-military models-they show up surplus on occasion,or on EBay.

The filter may work, but first you need a lamp, which has sufficient emission in the near (shorter wave) IR range. The thing is, general service lamps are designed to maximise the visible output, all the losses are then in the form of convection heat or the long wave (10um range)  IR mainly from the outer glass.
What I remember, quite strong and efficient near IR radiator is Xenon, but you would need pure Xenon lamp, without the halide fill (the fill metals tend to take over all the energy and then radiate it in visible, so nothing gets left for the Xenon). I would not be surprised the military lanterns are actually pure Xe arc with Woods glass (or similar) filtering.

The filter may work, but first you need a lamp, which has sufficient emission in the near (shorter wave) IR range. The thing is, general service lamps are designed to maximise the visible output, all the losses are then in the form of convection heat or the long wave (10um range)  IR mainly from the outer glass.
What I remember, quite strong and efficient near IR radiator is Xenon, but you would need pure Xenon lamp, without the halide fill (the fill metals tend to take over all the energy and then radiate it in visible, so nothing gets left for the Xenon). I would not be surprised the military lanterns are actually pure Xe arc with Woods glass (or similar) filtering.

Doesn't Xenon also emit loads of visible light? (Camera flashes)
A good use of any visible light is a warning of high power infrared light.

It does, but the efficiency in IR is way higher.
To conceal the lamp, you need heavy filtering anyway.
Every HID emits many lines, always only few are in the desired range. The rest form losses. And if they are not wanted, you have to filter them out.
So when the Xe emits a lot in visible and there are applications utilizing that (and where the IR are the losses responsible for otherwise rather low raw efficacy of Xe discharges), in this case the visible range belong to the losses and the IR is the useful output.

The only light source without any parasitic emission is then the LED and I think that is the best short wave IR source from all available for "mortals" (so without access to some military stuff or so).

The next type I know with very limited parasitic emissions is the FEL, but that is really just a scientific and/or really special military equipment (high power - starts in 10's of kW radiated output, very high cost, very dangerous when not handled properly; these are really big devices)

The problem comes when you need to cool the LED. 

The problem comes when you need to cool the LED. 

C'mon, that is not that difficult, unless you do something impossible.

With LED modules you should never forget the rating means really the absolute maximum, defined as (loose citation from ISO)
"ABSOLUTE MAXIMUM RATINGS are limiting values
of operation and should not be exceeded under the worst
conditions. These values are chosen to provide acceptable
serviceability of the device. The equipment manufacturer
should design so that initially, and throughout life, no
absolute maximum value is exceeded. If exceeded, even if
the device continues to operate, its life may be considerably
shortened."

In real life and practical designs it means with most LED's the usable power loading is about half of the rating or even less.
With IR LED's, the limiting factor would be the current capability of the bondwire. Fortunatelly the cathode uses to be the substrate, so the only bondwire is on the anode side and there the current is flowing from the bondwire into the chip, what makes the electro migration somewhat slower.

You need a diffuse light, that makes the thing easier: If you need 100W, use 4x "50W" modules or even better 8x "25W" ones and feed them by the 100W total.
Or you may just get the big lot of the 5mm LED's (they are among the cheapest ones, yet offer some output focus) and connect them on a common board. With that keep them with at least 10mm distance from each other and keep the package at least 8mm  from the board to allow thermal expansion without causing strain on the LED assembly (not respecting this is the main reason for early failures with most assemblies using this LED format).
If you do not want the narrower beam, then go for some SMD format, like 5050 or 2016 or so. Better stay away from the "0805" or "1206" or similar resistor-like formats - they do not offer anything to compensate for thermal expansion, so the soldering tends to crack. Even with these keep them 10mm apart (the 2016; the 5050 even further, because they are of higher power). With this you will get the power input of about 0.2W per square inch of board space and that should be handled well with the LED's/board itself, without any explicit heat sink.