Image pickup optical system and digital apparatus using the same
AssigneeKonica Minolta Opto, Inc.
InventorMasashi Isono
Life of this patent
Estimating the term…
Abstract
An image pickup optical system comprising three lenses for forming an image on a solid imaging element, wherein the comprised lenses are, from an object side, a positive first lens (FL1) whose convex surface is directed toward the object side, an aperture stop (ST), a negative second lens (FL2) and a negative third lens (FL3), and the following conditional expression is fulfilled, −0.23<f/f2<−0.02 provided that: f: a focal length of the entire system; and f2: a focal length of the second lens (FL1)
Claims9
An image pickup optical system for forming an image on a solid image element, essentially consisting of from an object side:
- a first lens having a positive power whose convex surface is directed toward the object side;
- an aperture stop;
- a second lens having a negative power;
- and
- a third lens having a negative power,
- wherein the following conditional expression is fulfilled,
- −0.23<f/f2<−0.02
- where
- f:
- a focal length of the entire system;
- and
- f2:
- a focal length of the second lens.
An imaging apparatus comprising:
- imaging elements for converting an optical image to an electrical signal;
- and
- an image pickup optical system that forms an optical image of the object on a receiving surface of said imaging elements,
- wherein said image pickup optical system essentially consists of from an object side:
- a first lens having a positive power whose convex surface is directed toward the object side;
- an aperture stop;
- a second lens having a negative power;
- and
- a third lens having a negative power,
- and wherein the following conditional expression is fulfilled,
- −0.23<f/f2<−0.02
- where
- f:
- a focal length of the entire system;
- and
- f2:
- a focal length of the second lens.
A digital apparatus comprising an imaging unit which includes imaging elements for converting an optical image to an electrical signal, and an image pickup optical system that forms an optical image of the object on a receiving surface of said imaging elements,
- wherein said image pickup optical system essentially consists of from an object side:
- a first lens having a positive power whose convex surface is directed toward the object side;
- an aperture stop;
- a second lens having a negative power;
- and
- a third lens having a-negative power,
- and wherein the following conditional expression is fulfilled,
- −0.23<f/f2<−0.02
- where
- f:
- a focal length of the entire system;
- and
- f2:
- a focal length of the second lens.
Dependencies are inferred from the claim text.