What does focal length mean?

Definitions for focal length

Here are all the possible meanings and translations of the word focal length.

Princeton's WordNet

  1. focal distance, focal length(noun)

    the distance from a lens to its focus


  1. focal length(Noun)

    The distance at which something (e.g. a lens, mirror etc.) is in focus; in air it is the distance along the optical axis from a "principal plane" of the lens to one of the lens's focal points.


  1. Focal length

    The focal length of an optical system is a measure of how strongly the system converges or diverges light. For an optical system in air, it is the distance over which initially collimated rays are brought to a focus. A system with a shorter focal length has greater optical power than one with a long focal length; that is, it bends the rays more strongly, bringing them to a focus in a shorter distance. In most photography and all telescopy, where the subject is essentially infinitely far away, longer focal length leads to higher magnification and a narrower angle of view; conversely, shorter focal length or higher optical power is associated with a wider angle of view. On the other hand, in applications such as microscopy in which magnification is achieved by bringing the object close to the lens, a shorter focal length leads to higher magnification because the subject can be brought closer to the center of projection.


  1. Chaldean Numerology

    The numerical value of focal length in Chaldean Numerology is: 2

  2. Pythagorean Numerology

    The numerical value of focal length in Pythagorean Numerology is: 4

Images & Illustrations of focal length

  1. focal lengthfocal lengthfocal length

Translations for focal length

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"focal length." Definitions.net. STANDS4 LLC, 2018. Web. 21 Feb. 2018. <https://www.definitions.net/definition/focal length>.

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