Helium-Neon Laser Mirror Kit 1

This is a set of *unmounted* dielectric mirrors of various radii of curvature (RoC) and reflectivities (includes OCs and HRs) which are ideal for experiments on resonator stability and mode structure with external cavity HeNe laser tubes and heads. These are all very high quality mirrors that are intended for laser use, specifically for installation in HeNe lasers.

The default kit includes 1 each of the following 5 mirrors. Due to availability, I may substitute a slightly different mirror in some cases but they should be suitable for the same experiments. All of these are new (NOS).

All of these mirrors should work with the 1-B tubes and heads sold separately. However, the range of distances from the B-window at which lasing occurs will depend on the particular mirror curvature. Intracavity and output power will depend on the reflectivity as well. In some cases, the mirrors can be turned around and will still result in lasing under certain conditions (though the output power will be reduced somewhat). The working distances in all cases are left as an exercise for the student! Hint: Solve the g1g2 equation for each mirror. The RoC of the internal HR mirror in the 1-B tubes is 60 cm.

The mirror selection, above, is subject to change without notice.

The mirrored surface will arrive in a usably clean state. A photographic air bulb or similar device may be used to blow off dust but DON'T TOUCH the mirror surface with ANYTHING! If the mirror is stored in a closed container or the packaging it came in, it will remain clean. Even if in an open lab environment, if mounted vertically or with the coated surface facing down, dust will not tend to collect on the mirrors. However, should the need for cleaning arise, PROPER LASER MIRROR CLEANING PROCEDURES MUST BE USED or else the delicate mirror coatings can easily be ruined!!!! See Sam's Laser FAQ in section: Cleaning of Laser Optics. And, before blaming the mirror, it's much more likely that the Brewster window of your laser tube is dirty, especially if it is facing up!

We will not be responsible for damage to mirrors caused by abuse!

I would suggest using the 45 or 60 cm RoC mirrors a few inches from the B-window first. These should easy to get lasing and enable the B-window to be cleaned while lasing using a cotton swab. (The Brewster window is reasonably robust, though excessive rubbing should be avoided.) Once you have some experience, other configurations will be easy.

It will be necessary to secure these mirrors in a holder that will enable them to be installed on an adjustable mount (for alignment) and will protect them from damage and contamination. Where optical table components are available, adapter cylinders can be easily fabricated to enable standard (e.g., 1/2" or 1") adjustable mounts to be used. Additional options are described in Sam's Laser FAQ in the section: Mounting Laser Mirrors. Alternatively, three tiny dabs of 5 minute Epoxy can be applied around the periphery. DON'T use any solvent-based glues, especially cyanacrylics like SuperGlue(tm)!

With a reasonably steady hand, it's possible to get lasing flashes, and even sustained lasing simply by holding the mirror in front of the B-window and carefully adjusting its orientation to aim the bore light back into the tube. Impress your friends! :)