Single-focus lens
AssigneeFuji Photo Optical Co., Ltd.
InventorKenichi Sato
Life of this patent
Estimating the term…
Abstract
A single-focus lens includes from the object side, a first lens with a positive refracting power having at least one aspheric surface, a stop, a second lens with a negative refracting power, and a third lens with a positive refracting power having at least one aspheric surface. This single-focus lens further satisfies the conditional expression of 0.3<f/f2′3<0.8, where f is the focal length of the lens as a whole, and f23 is the composite focal length of the second and third lenses.
Claims5
A single-focus lens comprising, successively from the object side, a first lens with a positive refracting power having at least one aspheric surface, a stop, a second lens with a negative refracting power, and a third lens with a positive refracting power having at least one aspheric surface;
- and satisfying the following conditional expression (1):
- 0.3f′/f′23<0.8 (1)
- where
- f′ is the focal length of the lens as a whole;
- and
- f′23 is the composite focal length of the second and third lenses.
Dependencies are inferred from the claim text.