Assertion: telephoto lens's length | /r/HasProperty | given by the distance
Facets:
value: between the center of the lens
type: LOCATION
value: between the focus point
type: LOCATION
Source sentences:
text: Parallel rays entering the lens will focus at some point (F), and the focal length (f) is given by the distance between the center of the lens (the optical center) and the focus point.