Zoom lens and optical apparatus having the same
AssigneeCanon Kabushiki Kaisha
InventorYoshinori Itoh
Life of this patent
Estimating the term…
Abstract
A zoom lens of the negative lead type includes, in order from the object side, a first lens unit of negative refractive power, a second lens unit of positive refractive power, a third lens unit of negative refractive power consisting of one negative lens, and a fourth lens unit of positive refractive power consisting of one positive lens, wherein, during zooming from the wide-angle end to the telephoto end, all the lens units move along an optical axis in such a manner that the separation between the first lens unit and the second lens unit decreases, the separation between the second lens unit and the third lens unit increases and the separation between the third lens unit and the fourth lens unit decreases.
Claims35
A zoom lens comprising, in order from an object side to an image side:
- a first lens unit of negative refractive power;
- a second lens unit of positive refractive power;
- a third lens unit of negative refractive power, said third lens unit consisting of one negative lens;
- and
- a fourth lens unit of positive refractive power, said fourth lens unit consisting of one positive lens,
- wherein, during zooming from a wide-angle end to a telephoto end, all the lens units move along an optical axis in such a manner that a separation between said first lens unit and said second lens unit decreases, a separation between said second lens unit and said third lens unit increases and a separation between said third lens unit and said fourth lens unit decreases.
A zoom lens comprising, in order from an object side to an image side:
- a first lens unit of negative refractive power, said first lens unit including a negative lens, a positive lens and an aspherical lens;
- a second lens unit of positive refractive power;
- a third lens unit of negative refractive power, said third lens unit consisting of one negative lens;
- and
- a fourth lens unit of positive refractive power,
- wherein, during zooming from a wide-angle end to a telephoto end, every adjacent two of the lens units move along an optical axis while varying a separation therebetween.
A zoom lens comprising, in order from an object side to an image side:
- a first lens unit of negative refractive power;
- a second lens unit of positive refractive power;
- a third lens unit of negative refractive power;
- and
- a fourth lens unit of positive refractive power, said fourth lens unit consisting of one aspherical positive lens,
- wherein, during zooming from a wide-angle end to a telephoto end, every adjacent two of the lens units move along an optical axis while varying a separation therebetween.
A zoom lens comprising, in order from an object side to an image side:
- a first lens unit of negative refractive power, said first lens unit including a negative lens, a positive lens and an aspherical lens;
- a second lens unit of positive refractive power;
- an aperture stop;
- a third lens unit of negative refractive power, said third lens unit consisting of one negative lens;
- and
- a fourth lens unit of positive refractive power,
- wherein, during zooming from a wide-angle end to a telephoto end, every adjacent two of the lens units move along an optical axis while varying a separation therebetween.
Dependencies are inferred from the claim text.