Jon's Homebuilt Lasers - First Nitrogen Laser Project

Created: 01/21/2002 Last Update: 01/21/2002

BELOW: This is a shot of the cavity I used for the N2 laser it is made out of acrylic(aka PlexiGlas(tm)). The owner of a local plastics shop manufactured this to my specifications. There's probably some design changes I will make, but that's for the Model 2 nitrogen laser I guess :). It consists of two halves with a wide channel cut in them. I then drilled the electrodes and the acrylic to place 10 clamping bolts, and added to holes for vacuum and gas feed. The ends are also plexi plates with holes drilled in them, and microscope slide glass over the holes. The whol assembly was sealed and glued using clear silicone sealant.

Custom N2 Laser Cavity Side View Custom N2 Laser Cavity Top View

BELOW: This is the overall view of the N2 laser. The copper plates are the top plates of the cap, they are glues to a mylar film sheet underneath and just below that is another copper sheet across the full width. The big what plastic part is my pressurized spark gap. The gas feed is on the right nipple(not connected in this shot) and then the exhaust is on the left. It flows into the needle valve and through the laser cavity. The vacuum is connected to the front of the laser.

Nitrogen Laser Overview

BELOW: This is a closer shot of the spark gap. Not very complex construction and I have pressurized it up to 40PSI. The bolt on the top can be adjusted up and down to set the spacing of the gap inside. Seals for the adjustable bolt were made of washers and inner-tube rubber and worked pretty good. The spark gap GREATLY reduced operational noise of this laser.

Nitrogen Laser Spark Gap

BELOW: I managed to waste a couple of dieelectrics before I found one I could lase on. However, once I moved to a bigger transformer, the dielectric that WAS working for me failed. Due to lack of a source for thicker dielectrics at the moment, I have stopped this project. If you know of a supplier of rolls of .015" mylar film, please let me know. The first pic is the garbage bag which worked for a bit, the second pic is a material I don't remember the name of shot over the top of my keyboard :)

Damaged Dielectric

Below: The rest of this page is random shots of the N2 laser in operation. The green dye in front of the laser is not a laser dye, but a flourescent printers dye. This laser was not able to excite my R6G solution very well, partially due to low output power, and partially to the fact that the R6G I have is not mixed for a dye cell, but for a dye jet configuration(ie, argon laser pumped) I'm sorry they're so blurry, but my current camera doesn't do close up's real well.

Dye Fluorescing Under Laser