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FrozenGate by Avery

Portable Iodine vapour laser pumped with a diode laser!? A real Possibility?

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Jul 4, 2008
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Well, I was investigating chemical laser technology yesterday when I stumbled on a very interesting article relating to Iodine vapour and it's unique property for absorbing ~515nm (green) laser light. An experimental laser has been built using a Ar ion laser as the pump laser and a transmission filter to block all but the ~500-515nm emission lines (I forget how many lines in Ar are produced, there are several) . The Iodine vapour is contained within a dye-cell. The green light interacts with the Iodine vapour to produce a nice beam of 633nm laser light. This kind of laser is known as an extended cavity laser. I am sure many of you laser nuts knew about these already...
Experiments with I2 and secondary resonance have been on-going since about the 1970's when lasers were restricted to Q-switched yag and large gas lasers. So... why is this interesting. It seems with the onset of new green diodes (512nm, 515nm, 520nm), mini- I2 vapour laser cells can be produced. (could be lots of fun?!) The experiment conducted in the 1970's showed that a multitude of spectra from 1.3um to nearly 600nm was able to produce secondary resonance in Iodine metal vapour. Kool!! :drool:

: Byer, R. L.
Microwave Laboratory, Stanford University, Stanford, California 94305 Jun. 1972.:
have observed stimulated emission in optically pumped molecular iodine vapor. Laser action occurs in more than 150 individual lines which span the spectral region from 544 to 1.335 nm for excitation by the 530‐nm second‐harmonic wavelength of a Q‐switched Nd:YAG laser. The iodine laser oscillates for input pulse energies of a few microjoules. Approximately 106 individual laser transitions may be excited by various pump frequencies.


So... my experiment.. I'd like to try, is to build a diode pumped I2 extended cavity laser, once I am able to get my hands on one of those new green projector diodes!!! Looks like a fun experiment to try. Question, will a 90mW-100mW "green" diode laser be able to make I2 vapour lase? It looks like a fun experiment to try.

!!!DANGER!!!
For those of you who want to attempt at building such a laser, Iodine is extremely toxic and stains just about anything it touches. It is also a potent oxidizer/ dangerously Reactive, though less so than Chlorine gas.
Take appropriate safety measures when using metallic Iodine and Iodine Vapour.

I have included a short video on how to make your own Iodine crystals...





Follow the instructions carefully. Use a fume hood or do this Iodine production outside.
The chemicals used in the production of Iodine are EXTREMELY corrosive. 98% Sulphuric Acid can burn you instantly. If it gets in your eyes it will blind you.
Even the vapours are HIGHLY corrosive. Elemental Iodine is Dangerously Reactive and causes all sorts of biological effects most of them effecting your Thyroid.
Iodine is a corrosive solid, so you should at least be wearing gloves to keep the iodine from touching your skin. Iodine also sublimes easily to form corrosive vapors. Working in a fume hood is the safest option if you have access, but not necessary of you're working with small amounts. If you aren't working in a fume hood keep the solid covered (and away from your face) to keep from breathing any of the dust or vapors. Depending on what concentrations you are making the solutions, they probably won't have any dangerous vapors, but could still possibly burn or irritate your skin.


Dye cells can be made easily with microscope slides... Remember You're going to have to heat the cell to produce the I2 vapour to about ~100c. Iodine sublimates quickly.
 
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Looks really interesting, Id like to try this as well a little later on! ;) :thanks:

BTW word of caution: Iodine also sublimes and recrystallises on eye balls doing untold damage! It was one of the things drummed into us working with it. Take care and dont let the purple vapour get near your eyes! :beer:
 
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Looks really interesting, Id like to try this as well a little later on! ;) :thanks:

BTW word of caution: Iodine also sublimes and recrystallises on eye balls doing untold damage! It was one of the things drummed into us working with it. Take care and dont let the purple vapour get near your eyes! :beer:

Which is why I am saying, if you are going to work with elemental Iodine, do this either in a fume hood or outside. ALWAYS wear safety goggles when working with Sulphuric Acid and Iodine.... yup... I have done this experiment in the video. I got pure Iodine from modifying the reaction. straight KI and 98% H2SO4 give a much better yield than mixing KI in Aq. I used Dry ice to flash form the I2 crystals on the upper flask. Worked beautifully.
 
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Yeah I know you did, but I thought Id just reiterate that important point. You hadnt mentioned the risk to the eyes from iodine, but had mentioned keeping it away from ones face. :beer:
 
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Yeah I know you did, but I thought Id just reitterate that important point. You hadnt mentioned the risk to the eyes from iodine, but had mentioned keeping it away from ones face. :beer:

Yup... indeed.

All the halogens are particularly corrosive to soft tissues.
Anyways, thanks for re-iterating the Corrosiveness to eyes. Basically, if one is to conduct this experiment do it in a controlled environment with Safety in mind at all times.

Just as what has been stated in the Video.
 





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