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T-number

noun

Definition of T-number

: a number that is similar to the f-number but takes into account the amount of light actually transmitted by a lens after loss by absorption and reflection and that equals the f-number divided by the square root of the transmittance

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History and Etymology for T-number

total light transmission + number

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Dictionary Entries near T-number

tnoyim

tnpk

TNT

T-number

T nut

to

TO

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