The Large Binocular Telescope in Arizona uses two monolithic borosilicate mirrors, each 8.4 meters in diameter, cast at the University of Arizona's Richard F. Caris Mirror Lab — the largest single-piece optical telescope mirrors in operation, larger monolithic mirrors being impractical to cast, transport, and support without segmenting or gaps.
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The Large Binocular Telescope in Arizona uses two monolithic borosilicate mirrors, each 8.4 meters in diameter, cast at the University of Arizona's Richard F. Caris Mirror Lab — the largest single-piece optical telescope mirrors in operation, larger monolithic mirrors being impractical to cast, transport, and support without segmenting or gaps.
The largest diameter of any single-piece (non-segmented) cast glass primary mirror used in an operating ground-based optical telescope.
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1 accepted Claim, with 1 linked evidence records.
Permanent ID limitsregistry.com/limits/LR-LARGEST-SINGLE-APERTURE-OPTICAL-TELESCOPE-MIRROR
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Limits Registry. LR-LARGEST-SINGLE-APERTURE-OPTICAL-TELESCOPE-MIRROR. Largest single-piece telescope primary mirror. 2026.