The diameter of the Hubble's light-gathering mirror is 94.5 inches, while the diameter of the Keck's segmented mirror will be 33 feet.
All proposed designs for the OWL are variations on a segmented mirror, since there is no technology available to build a monolithic 60- or 100-meter mirror.
The operation of a segmented mirror is somewhat more complicated than a monolithic one, requiring careful alignment of the segments (a technique called cophasing).
Its segmented, deployable mirror will be over twice as large, increasing angular resolution noticeably, and sensitivity dramatically.
Considerable improvement of the performance of the segmented mirror can be achieved by introduction of three degrees of freedom per segment: piston, tip and tilt.
A segmented mirror is an array of smaller mirrors designed to act as segments of a single large curved mirror.
The Keck I telescope, which was successfully tested with part of its segmented mirror in place last November, is based on an innovative design that some critics had considered risky.
The architectures are a telescope with a monolithic primary mirror and two variations of a telescope with a large segmented primary mirror.
The instrument used to detect the Cherenkov radiation usually comprises a large segmented mirror which reflects the Cherenkov light onto an array of photomultiplier tubes.
Projects for future extremely large telescopes (ELTs) generally depend on the use of a segmented primary mirror.