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English definition of “focal length”

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focal length

noun [C usually singular] uk   specialized us  
the distance between a point where waves of light meet and the centre of a lens
Translations of “focal length”
in Chinese (Traditional) 焦距…
in Chinese (Simplified) 焦距…
(Definition of focal length from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
What is the pronunciation of focal length?
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