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All About Glass

All About Glass

This is your resource for exploring various topics in glass: delve deeper with this collection of articles, multimedia, and virtual books all about glass. Content is frequently added to the area, so check back for new items. If you have a topic you'd like to see covered, send us your suggestion. If you have a specific question, Ask a Glass Question at our Rakow Research Library.

The Hale Reflecting Telescope at Palomar

Lenses are used in refracting telescopes. Mirrors are used in reflecting telescopes. The mirrors are ground and polished so that a precise concave surface remains to be coated with a shiny, reflective finish. Mirrors concentrate light and focus all colors of the spectrum in an image. No lens can