TERMIUM Plus®

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OUVERTURE RELATIVE [1 record]

Filter results by subject field Alphabetical list of terms

Filter results by subject field

Alphabetical list of terms

Record 1 1999-03-24

English

Subject field(s)
  • Photography
  • Optics
  • Optical Instruments
DEF

The ratio of the focal length of a lens to the diameter of the effective aperture - the so called f number.

French

Domaine(s)
  • Photographie
  • Optique
  • Instruments d'optique
DEF

Diamètre utile d'un objectif ou d'une lentille par lequel passe la lumière.

OBS

On le calcule en déterminant le rapport entre le diamètre du diaphragme et la longueur focale de l'objectif.

Spanish

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TERMIUM Plus®, the Government of Canada's terminology and linguistic data bank
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