Zoom lens and imaging apparatus
AssigneeFUJIFILM Corporation
InventorsHiroki SAITO, Michio CHO, Toru ITO
Life of this patent
Estimating the term…
Abstract
A zoom lens includes: a first lens group having a negative refractive power; and a second lens group having a positive refractive power, provided in this order from an object side. Magnification is changed by moving the first lens group and the second lens group. The first lens group includes a first lens having a negative refractive power, a second lens, a third lens having a negative refractive power, and a fourth lens having a positive refractive power, provided in this order from the object side. The zoom lens satisfies predetermined conditional formulae.
Claims18
A zoom lens, substantially consisting of:
- a first lens group having a negative refractive power;
- and
- a second lens group having a positive refractive power, provided in this order from an object side;
- the first lens group and the second lens group being moved to change magnification;
- the first lens group substantially consisting of a first lens having a negative refractive power, a second lens, a third lens having a negative refractive power, and a fourth lens having a positive refractive power, in this order from the object side;
- and
- the zoom lens satisfying the following conditional formulae:
- −0.11<fw/fG12<0.12 (1-1)
- 0.31<fw/f2<0.49 (2-1)
- wherein fG12 is the focal length of the second lens from the object side within the first lens group, fw is the focal length of the entire system at a wide angle end, and f2 is the focal length of the second lens group.
A zoom lens, substantially consisting of:
- a first lens group having a negative refractive power;
- and
- a second lens group having a positive refractive power, provided in this order from an object side;
- the first lens group and the second lens group being moved to change magnification;
- the first lens group substantially consisting of a first lens having a negative refractive power, a second lens, a third lens having a negative refractive power, and a fourth lens having a positive refractive power, in this order from the object side;
- and
- the zoom lens satisfying the following conditional formulae:
- −0.04<fw/fG12<0.50 (1-3)
- 0.00<fw/f2<0.35 (2-3)
- wherein fG12 is the focal length of the second lens from the object side within the first lens group, fw is the focal length of the entire system at a wide angle end, and f2 is the focal length of the second lens group.
A zoom lens, substantially consisting of:
- a first lens group having a negative refractive power;
- and
- a second lens group having a positive refractive power, provided in this order from an object side;
- the first lens group and the second lens group being moved to change magnification;
- the first lens group substantially consisting of a first lens having a negative refractive power, a second lens, a third lens having a negative refractive power, and a fourth lens having a positive refractive power, in this order from the object side;
- the second lens group substantially consisting of four lenses;
- and
- the zoom lens satisfying the following conditional formulae:
- −0.04<fw/fG12<0.50 (1-3)
- 0.00<fw/f2<0.43 (2-7)
- wherein fG12 is the focal length of the second lens from the object side within the first lens group, fw is the focal length of the entire system at a wide angle end, and f2 is the focal length of the second lens group.
Dependencies are inferred from the claim text.