Hello guys!
Im in the very early start of the build of a CO2 laser and i want to put one together only because i have wanted to build one during a long time so it is not really planned to be for any practical use or so. There are however some questions i cant really find answers to so i thought that maybe someone here might know anything about them:
1. The HR must (?) be concave as i have understood but its dam hard to find these and especially smaller one and also with a radius of curvature at some few meters and at the same time copper coated (yea good luck). I might be able to get an ordinary plano-concave lens only with about right curvature but since i could coat it with copper my self so would that be fine anyway. It would however of course be much easier to just use plain flat glass and then surface coat this with copper but how would the laser react to a flat HR, if it would even lase at all? More power, less power, different divergence or something else?
2. What would be best; copper or aluminum? Gold sure but im not that rich and it would also need little special things to be able to evaporate which i don’t have.
3. It will be a sealed laser with o-rings and such for simplicity and to not use gas all the time since it's a real pain to get hold on the helium so thus sealed. Since its sealed so what i have understood so do you need to recombine the breakdown of the CO2 to CO so it will recombine to CO2 again. I have read somewhere that if something was glowing red hot in contact with the gas or even just a patch of gold or nickel (?) could act as a catalyst and recombine the CO to CO2 again but i don’t really know since i have found very little detailed information about this. Anyone know more exact about this? There will of course need to be oxygen in some sort like watervapor or so for the recombination.
3. A neon transformer would have been the perfect choice at least for little lower power levels i guess but where i live these doesn’t grow on trees as they do in the USA for example. Where i live there is pretty much no surplus market or similar what so ever for these. Would it otherwise be possible to use the HV transformer from an old TV to get several 10 of Watts out to he laser for longer periods as well if i use a fat transformer or would they not cope with that?
4. I guess borosilicate glass is an absolute must even if it was a laser with only a very few watts? If it would work with plain glass i could pretty much get any sized tube i want.
My plans for this laser:
Length: Most likely a small boring 300mm long. Hopefully and a little more interesting 600mm or most wanted 1 meter+. Reason not any longer then 300mm is just because i cant get any longer borosilicate tubes which annoys the hell out of me since i would like it to be meter long and i dont have enough heat in any way to melt several together.. which also annoys the hell out of me.
Width: Inner diameter around 6–8mm and once again due to the only tubes i can get in borosilicate glass. Ebay is the only source i know of that ship international as well but i have also read that the laser could work a little better due to the plasma getting chilled little better due to the closer approximity to the inner wall.
HR: Flat or concave with a radius of curvature of 2 meter, which i think would be all right for 300 - 1000mm length and the ID?
OC: 75% reflective if i later on would like to up the power but i might be with anything between 60 – 90% for all i know. This since i will do the OC my self so will the reflectivity be quite coarse since i will eyeball this due to the lack of right equipment..
Would all this add up to a functionally laser or might something be so totally way off that i should be banned for live?
Im in the very early start of the build of a CO2 laser and i want to put one together only because i have wanted to build one during a long time so it is not really planned to be for any practical use or so. There are however some questions i cant really find answers to so i thought that maybe someone here might know anything about them:
1. The HR must (?) be concave as i have understood but its dam hard to find these and especially smaller one and also with a radius of curvature at some few meters and at the same time copper coated (yea good luck). I might be able to get an ordinary plano-concave lens only with about right curvature but since i could coat it with copper my self so would that be fine anyway. It would however of course be much easier to just use plain flat glass and then surface coat this with copper but how would the laser react to a flat HR, if it would even lase at all? More power, less power, different divergence or something else?
2. What would be best; copper or aluminum? Gold sure but im not that rich and it would also need little special things to be able to evaporate which i don’t have.
3. It will be a sealed laser with o-rings and such for simplicity and to not use gas all the time since it's a real pain to get hold on the helium so thus sealed. Since its sealed so what i have understood so do you need to recombine the breakdown of the CO2 to CO so it will recombine to CO2 again. I have read somewhere that if something was glowing red hot in contact with the gas or even just a patch of gold or nickel (?) could act as a catalyst and recombine the CO to CO2 again but i don’t really know since i have found very little detailed information about this. Anyone know more exact about this? There will of course need to be oxygen in some sort like watervapor or so for the recombination.
3. A neon transformer would have been the perfect choice at least for little lower power levels i guess but where i live these doesn’t grow on trees as they do in the USA for example. Where i live there is pretty much no surplus market or similar what so ever for these. Would it otherwise be possible to use the HV transformer from an old TV to get several 10 of Watts out to he laser for longer periods as well if i use a fat transformer or would they not cope with that?
4. I guess borosilicate glass is an absolute must even if it was a laser with only a very few watts? If it would work with plain glass i could pretty much get any sized tube i want.
My plans for this laser:
Length: Most likely a small boring 300mm long. Hopefully and a little more interesting 600mm or most wanted 1 meter+. Reason not any longer then 300mm is just because i cant get any longer borosilicate tubes which annoys the hell out of me since i would like it to be meter long and i dont have enough heat in any way to melt several together.. which also annoys the hell out of me.
Width: Inner diameter around 6–8mm and once again due to the only tubes i can get in borosilicate glass. Ebay is the only source i know of that ship international as well but i have also read that the laser could work a little better due to the plasma getting chilled little better due to the closer approximity to the inner wall.
HR: Flat or concave with a radius of curvature of 2 meter, which i think would be all right for 300 - 1000mm length and the ID?
OC: 75% reflective if i later on would like to up the power but i might be with anything between 60 – 90% for all i know. This since i will do the OC my self so will the reflectivity be quite coarse since i will eyeball this due to the lack of right equipment..
Would all this add up to a functionally laser or might something be so totally way off that i should be banned for live?
