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18" Pyrex Deep Spherical Mirror (REDUCED) Sold!

Price - $150.00

Ad Number: 106932

Posted: 30 May 2017

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Now on Sale!!!!
Acquired this from Don Dilworth years ago. Was originally crated and shipped to University of Alabama from an optical fabricator. A paper tag on the back says 11/4/63, and the number 1689. (or could be 6891) engraved..

It measures 18" across, has a radius of 18" and weighs 34#. It is molded very light green glass, and is a conical/ meniscus pattern with a recessed 3/4" central hole, and 3 radially spaced holes. It has a chip at the rear edge of the central hole, which is probably why it was taken out of service.... I hate it when that happens.

The coating is scuffed and etched in places. I doubt the glass is scratched, but could strip it and verify.

I set up a crude Ronchi test using a laser pointer with lens removed and verified that it is spherical. I haven't quantified the quality of the sphere because of the deep curve, but it looks very nice. The edge has been faced flat for 3/16" so to me that means getting rid of the extreme edge. Texereau did this. So do I.

I heard it was part of the Terabeam projects.

Picture 1909. General view of front surface
Picture 1910. General view of molded back surface
Picture 1911. Central hole in back showing old cement and the chip
Picture 1912. View through the front showing coating and 3 radial holes.
Picture 18 f0.5 The edge showing the ground face.

Buyer pays shipping, please.

Reduced, was $225


  • Condition Used
  • Location 04353

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