Jarrod's Dirty CO2 Laser Design

This video explores the use of ordinary first surfaced mirrors on the ends of the laser tube (output end and high reflector end), as well as an ordinary piece of rock salt for the window through which the beam must pass. At the expense of performance, such a design lends itself to low budget amateur construction using the most basic supplies available.

When properly aligned, the laser actually works quite well considering the crude parts that are used. It will quickly char wood without focusing at close range, and will bring the resulting carbon to a bright yellow incandescence. Although more divergent than the beam from a laser with a proper output coupler, the beam from this laser does not appear to be as divergent as I had expected. This might suggest that although translucent at visible wavelengths, the rock salt could actually be more transparent to the CO2 laser output, which falls in the 10.6 micrometer range.

Carbon Dioxide can be supplied by mixing baking soda and vinegar, or by exhaling directly into a balloon. When using exhaled breath for the carbon dioxide, I take a deep breath and hold my breath as long as I can before exhaling into the balloon. Irregardless of the CO2 source that is chosen, the addition of helium makes the performance much better. I increase the helium ratio a little at a time until performance is good. Too much helium is not good (never breathe or inhale helium - I always exhale into the balloon first, and THEN add helium). It takes some trial and error to determine what is needed to obtain good results. However, I am thoroughly pleased with the performance given the crude supplies with which this laser is constructed.

CO2 lasers are potentially hazardous devices. The electrical power supply can kill instantly. The laser output can permanently maim, disfigure, or otherwise result in very serious injury. It is not a toy! It is many orders of magnitude beyond the limits of so called 'high power' hand held lasers, in terms of output power. The beam is totally invisible, and special measures must be taken to avoid accidental exposure to the direct, reflected, or scattered output. I disclaim all responsibility associated with the construction of, or use of such a device. This information is provided for education/entertainment purposes only. It involves amateur construction, and I disclaim all responsibility for any damage or injury, as well as for errors or omissions, regarding all forms of content I have provided on all subjects.

For more information on this laser, as well as some of my others, please visit my homepage (all webpages under construction, and far from complete at this time) here:

http://jarrodkinsey.org/

Category:

Science & Technology

Tags:

• jarrod
• physics
• lasers
• laser
• high voltage
• science
• scientist
• radiation
• technology
• energy
• infrared

[VALKIR4636]

that real output coupler looks a lot like a disk from a hard drive ... i took an old one apart, there were 4-5 disks with arguably the exact same coloring. they were pretty reflective (until i left fingerprints all over them) and have the gold-ish tint. no idea if it's usable but give it a shot. who knows, it might be a better alternative to what you're using. the only problem is the hole in the middle ... but i guess you can work around that if you wanted to :)

[magx1]

@VALKIR4636 Are these disks made out of metal? If not brittle like glass or ceramic, it might be much easier to drill a hole through them. You might have an excellent idea here. Thanks.

I've used copper for an OC. It works, except that I cannot attempt a mirror like finish without scratching it. I also cannot make it perfectly flat. Any help/suggestions with how to achieve this would be greatly appreciated. Metal would be ideal due to the fact that it isn't brittle, and is easier to drill.

[lexichronicle2]

@magx1 I've got to agree with the 'Holy fucking shit!' comment below. Over 9000 hacker points awarded! Can't praise you experimentalism enough.

For drilling, make sure you cool the bit with water and consider using a high speed drill and a press.

Hard drives would be good as the surface is micronically / nano flat. They are often ceramic though (drill carefully / slowly).

For polishing the metals, lap them on a piece of float glass using paste.

[magx1]

@lexichronicle2 The praise goes to my Savior and Lord, Jesus Christ. No other.

[nehockc]

Will this tubing work to start out with?

inner tube - Borosilicate Glass Tubing 12 mm x 24"

Cooling Tube - Shop Metalux 4' Tube Guard T12 from Lowes??

[dtiydr]

@magx1 If you might not have noticed this yet so are 3.5" discs made of aluminum but 2.5" is made of glass.

[kungfumaster12]

this is really cool.. :)

[straygypsy]

Can the laser go through pink footballs????

[SINCLAIRRESEARCH]

kove the wexperimental nature you have , this is always the best way to innovation well done !!! and a happy new year to you and your family

keith and family

[VALKIR4636]

@lexichronicle2 i was thinking of running a file across the edge of the platter. that will be evident of wether it's ceramic or aluminum ( but i had already posted the comment :D ). the DIY mirror is a good approach if the material is hard (like ceramic) but that poses the problem that it'll be brittle when he drills holes in it.

food for thought or what haha

[lexichronicle2]

@VALKIR4636 Tap them, aluminium won't make the same sound / feel the same as ceramic. or try notched a side / drilling a test hole on the edge. checking the density would be a plan too.

I've also had another thought, since going to get a cup of coffee, you could use the platter as your reference standard for lapping; doing the windows & mirrors directly on the platter with a blob of compound on there.

you should be able to get very high numbers on the finish that way - needs to be ceramic tho

[VALKIR4636]

@magx1 a short wiki search on "hard drive platter" yields: "typically made using an aluminium or glass and ceramic substrate". they may be brittle if you get the glass/ceramic type ... dunno how you can determine the platter material just by looking at the HDD. they're the size of a ordinary CD. i'm guessing that the aluminum ones will be lighter than the glass/ceramic ones. only way to find out is trial and error :) you can get cheap old 100-500mb hard drives with a few platters in them ;)

[lexichronicle2]

You may also be able to lap the DIY windows once they're on, to get a more uniform wavefront profile.