Jason's Laser Page

Go ahead, make my day!

On May 11, 2001 myself and two jr. high boys (Jonathan Graham and Caleb Tullis) built an atmospheric pressure nitrogen laser using air as the lasing medium.  I was inspired to do this project by a very descriptive web page which is no longer available. The article contained valuable information despite the fact that it was poorly translated into English from German.  For a brief description of the theory behind nitrogen laser see Rami Arieli's:"The Laser Adventure".  Mark Csele also has a very good site about homebuilt lasers.  These pages and many other informative sources were found on Sam's Laser FAQ, an extensive and valuable resource for anyone interested in Lasers.  We were extremely thrilled when, two hours after we began throwing a prototype of the laser together on a table in my library, it sprung to life!  Since then I have improved on the design and built two different sizes.  The larger one has an 18 inch cavity and the smaller one has a 7.5 inch cavity.  The electrodes are 1/8 inch bar stock aluminum (available at any hardware or home-improvement store),  The spark gap is 8-32 machine screws anchored in angle stock aluminum and covered with stainless steel cap-nuts (see previous item),  The capacitor plates are generic heavy duty aluminum foil (from the grocery store),  and the dielectric is a 10 mil thick polypropylene sheet (dry-erase poster board).  I've also used cellulose acetate sheets and overhead projector transparency sheets.  The power supply is a 12 KV neon sign transformer (purchased used from a local neon sign shop), half-wave rectified by two NTE-517 microwave oven diodes (ordered from an electronics supplier), and current limited by 1M Ohms or 18 M Ohms of resistance depending on which terminal is connected.  For eye safety, I purchased several sets of polycarbonate safety goggles at a local hardware store.  They block the beam entirely! (note- the wavelength is in the near ultraviolet, and therefore invisible, but many materials are flourescent when exposed to intense UV radiation, white paper or cotton blend cloth glow bright blue where the beam hits them.)


Schematic Diagram

Original Concept Sketch

7.5 Inch Laser

18 Inch Laser

Power Supply

Photo by Andy J. Burnfield

Wavelength Measurement

Click on the links below to see photos and drawings!

Click here to find out more about Jason

I give live demonstrations and talks about lasers which can be customized for a wide range of audiences.  E-mail me if you are interested in having me come do a demonstration at your school or organization.