Ruby rod pumped by LED array

[matt304]

This is just something which I was thinking about. Red lasers are still weak, with diodes in the 650nm range only putting out a maximum of around 300mW. Not very good for a strong looking beam.

Ruby rods are known to be pumped by flash bulbs for a high pulsed output.

Since LEDs have become so powerful in recent years, many of them can be fit in a small space without producing huge amounts of heat as earlier light sources would. I wonder what would happen if a few rails of LEDs were aimed into a ruby rod.

I mean, surely it would lase, would it not? And to think that those small LEDs could be literally touching the rod, you would imagine it would be possible to get watts and watts of photons entering the rod.

What do you think?

 

[AJ_Dual]

I guess it would matter which spectral line in the Xenon strobe is the one doing most of the excitation of the chromium atoms that are in the ruby rod.

A Xenon or Krypton tube outputs a wide range of spectral lines, and is almost semi-continuous at the right voltage.

IIRC, the Chromium atoms in Ruby compounds excite the most from the blue/green portion of the spectrum. So maybe a tube of multi-Watt blue and green LED's could do the trick.

Although, if your goal is to simply make red more "visible", rather than going to a "scary Wattage" to make it visible, I'd get more human eye sensitivity with a slightly shorter but still "red" wavelength.

A high output 635nm diode will look a lot brighter than a comparable 650nm one.

 

[matt304]

Interesting about the blue/green.

I have built 650nm lasers over 300mW. Hell the sleds are only $15. But the beam is extremely weak. About like 10mW of green or so.

635nm diodes would still take about 150mW to look like 300mW of 650nm.

I can find no 635nm diodes that will output 150mW. In fact, I have only see them do under 20mW.

So, logically, the next step could be another jump to 670nm ruby, but with a watt or more of power. I have a few class 4 lasers and safety goggles.

 

[bshanahan14rulz]

or you might try to find a source for the high-power 635nm diodes. They exist, but nobody's found any yet. Or if you have a few thousand dollars you can buy a couple from the manufacturer. They will be multimode.