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

TNT

T-number

T nut

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Statistics for T-number

Cite this Entry

“T-number.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/T-number. Accessed 25 May. 2022.

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