The 1990s will see the construction of six to eight optical telescopes with effective diameters in the range 6.5 m
to 16m, all larger than any existing telescope. The huge increases in light-gathering power have come about only
through innovative mirror and telescope designs, for gravity
does not allow a simple scaling up of existing 4-m-class
telescopes. Thus, three new primary mirror concepts are
being pursued vigorously: the segmented mirror of the
10m Keck Telescope,1 which consists of 36 thin 1.8-m
segments of solid low-expansion glass ceramic; monolithic thin meniscus mirrors of the same material for the European Southern Observatory's 4
x 8.2-m Very Large Telescope2 and
the 7.5 m Japanese National Large
Telescope; and spin-cast borosilicate honeycomb mirrors up to 8 m in diameter for three projects involving the University of Arizona and two U.S. national telescope projects.
This article is only available as a PDF.
Publish Date: 01 June 1990
Log in or Become a member to view the full text of this article.
This article may be available for purchase via the search at Optica Publishing Group.
Optica Members get the full text of Optics & Photonics News, plus a variety of other member benefits.
Optical fabrication and testing: a historical review
International optical standards
Automation in optics manufacturing
Testing aspheric surfaces
Why measure MTF?
When is a surface clean?
Don't add more bureaucracy to standards, government told
Computer-Generated Phase-Only Holograms for 3D Displays: A MATLAB Approach
Lighting a Better Path to 3D-Printed Hydrogels
Reconfigurable Metasurfaces Control Light Precisely