Home Built 600 mm Vacuum chamber for optical coatings

This was the culmination of my Amateur Telescope Making obsession.

I built this vacuum chamber to coat various home made telescope mirrors with a thin optical layer of evaporated aluminum.

I had considered upgrading to include the ability to evaporate dielectric coatings but found that simple pure aluminum coatings were more than satisfactory for my needs.

Chamber specs:

The chamber is fabricated from cold rolled 12 mm mild steel plate which was MIG welded together and can achieve a pressure of slightly less than 2x10E-5 torr.

The back wall contains 18 tungsten evaporation points modeled to provide uniform coating thickness for any reasonably fast mirror optical system.

Pumping is done via a 1950's era water cooled Oil Diffusion pump running the same mineral based pump oil used in the Welch mechanical backing pump. Chamber pump down takes about 15 minutes and uses a crude but effective 'Glow Discharge' cleaning cycle.

Видео Home Built 600 mm Vacuum chamber for optical coatings канала James Lerch