Bent zoom lens
AssigneeTamron Co., Ltd.
InventorKazuya Watanabe
Life of this patent
Estimating the term…
Abstract
The bent zoom lens is configured to include, arranged in order from an object side, a first lens group GR1 having a positive refractive power, a second lens group GR2 having a negative refractive power, a third lens group GR3 having a positive refractive power, a fourth lens group GR4 having a negative refractive power, and a fifth lens group GR5 having a positive refractive power. The first lens group GR1 includes a single piece of meniscus lens having a negative refractive power and having a convex surface directed toward an object side, a prism that bends an optical path, and a single piece of double-convex lens having a positive refractive power.
Claims12
A bent zoom lens comprising:
- a first lens group including
- a front-side lens group having a negative refractive power,
- an optical member that bends an optical path, and
- a rear-side lens group having a positive refractive power;
- a second lens group;
- a third lens group;
- a fourth lens group;
- and
- a fifth lens group, the first lens group, the second lens group, the third lens group, the fourth lens group, and the fifth lens group arranged in order from an object side,
- wherein a value of |β52×(1−β4w2)| is set to be from approximately 1.0 to 2.0, and a value of |β52×(1−β4T2)| is set to be approximately from 1.0 to 2.0, where β4W represents an image-formation magnification of the fourth lens group at a wide-angle end when a distance to the object is infinite, β4T represents an image-formation magnification of the fourth lens group at a telephoto end when a distance to the object is infinite;
- and β5 represents an image-formation magnification of the fifth lens group when a distance to the object is infinite.
A bent zoom lens comprising:
- a first lens group including
- a front-side lens group having a negative refractive power,
- an optical member that bends an optical path, and
- a rear-side lens group having a positive refractive power;
- a second lens group;
- a third lens group;
- a fourth lens group;
- and
- a fifth lens group, the first lens group, the second lens group, the third lens group, the fourth lens group, and the fifth lens group arranged in order from an object side,
- wherein a value of |β5| is set to be approximately 0.5 or less, where β5 represents an image-formation magnification of the fifth lens group when a distance to the object is infinite.
A bent zoom lens comprising:
- a first lens group including
- a front-side lens group having a negative refractive power,
- an optical member that bends an optical path, and
- a rear-side lens group having a positive refractive power;
- a second lens group;
- a third lens group;
- a fourth lens group;
- and
- a fifth lens group, the first lens group, the second lens group, the third lens group, the fourth lens group, and the fifth lens group arranged in order from an object side,
- wherein a value of |β2T| is set to be approximately 1.0 or less, where β2T represents an image-formation magnification of the second lens group at a telephoto end when a distance to the object is infinite.
A bent zoom lens comprising:
- a first lens group including
- a front-side lens group having a negative refractive power,
- an optical member that bends an optical path, and
- a rear-side lens group having a positive refractive power;
- a second lens group;
- a third lens group;
- a fourth lens group;
- and
- a fifth lens group, the first lens group, the second lens group, the third lens group, the fourth lens group, and the fifth lens group arranged in order from an object side,
- wherein a value of |R4a|/R4b is set to be approximately 1.1 or less, where R4a represents a radius of curvature of a most object side surface of lenses constituting the fourth lens group, and R4b represents a radius of curvature of a most image side surface of the lenses.
Dependencies are inferred from the claim text.