Assertion: lens's length | /r/HasProperty | ffl
Facets:
Source sentences:
text: The distance from the front focal point of the combined lenses to the first lens is called the front focal length (FFL):
text: The distance from the front focal point of the combined lenses to the first lens is called the front focal length (FFL):
text: A zoom lens is a mechanical assembly of lens elements for which the focal length (and thus angle of view) can be varied, as opposed to a fixed focal length (FFL) lens (see prime lens).