focal length
— Noun
– English
～ the distance from a lens to its focus
family Lennoaceae
— Noun
– English
～ family of fleshy parasitic herbs lacking green foliage and having heads of small flowers; California and Mexico
fisheye lens
— Noun
– English
～ a camera lens having a wider than normal angle of view (and usually a short focal length); produces an image that is foreshortened in the center and increasingly distorted in the periphery
Fresnel lens
— Noun
– English
～ lens composed of a number of small lenses arranged to make a lightweight lens of large diameter and short focal length
field lens
— Noun
– English
～ the lens that is farthest from the eye in an optical device with more than one lens
family Lentibulariaceae
— Noun
– English
～ carnivorous aquatic or bog plants: genera Utricularia, Pinguicula, and Genlisea
family Lepidobotryaceae
— Noun
– English
～ family created in 1950 solely for the classification of a distinctive African tree repeatedly classified in other families; trees long believed to exist only in Africa
family Lepidodendraceae
— Noun
– English
～ fossil plants characterized by conspicuous spirally arranged leaf scars on the trunk
family Lepiotaceae
— Noun
– English
～ a family of fungi having free gills and a cap that is cleanly separable from the stalk