Zoom lens and image pickup apparatus using the same

A zoom lens comprising in order from an object side to an image side:

• a front unit having a negative refractive power;
• and
• a rear unit having a positive refractive power, which includes an aperture stop, wherein:
• in the front unit, all distances of adjacent lenses are not variable distance, and
• the rear unit includes at least three lens units, and
• in each lens unit, all distances of adjacent lenses are not variable distance, and
• in the at least three lens units, each lens unit is disposed so that all distances of adjacent lens units are variable distance, and
• the front unit includes a first lens having a negative refractive power, a second lens having a negative refractive power, and a third lens having a positive refractive power, and
• the first lens is disposed nearest to an object, and has a meniscus shape of which a convex surface is directed toward the object side, and
• the second lens is disposed on the image side of the first lens, and has a meniscus shape of which a convex surface is directed toward the object side, and
• the rear unit includes in order from the object side to the image side, a first lens unit A and a second lens unit B, and
• at the time of zooming from a wide angle end to a telephoto end, a distance between the front unit and the rear unit narrows, and a distance between the first lens unit A and the second lens unit B changes, and
• the first lens unit A includes a focusing lens unit having a positive refractive power, which is disposed on the object side of the aperture stop, and
• at the time of focusing, only the focusing lens unit moves along an optical axis, and
• the following conditional expressions are satisfied:
• 72<vdFnmax<110, and
• −1.8<fw×Fnowmin/fF<−0.5
• where,
• vdFnmax denotes a maximum of Abbe number from among Abbe numbers for lenses having a negative refractive power in the front unit,
• fw denotes a focal length of the overall zoom lens system at the wide angle end,
• Fnowmin denotes a minimum of F-number from among F-numbers at the wide angle end, and
• fF denotes a focal length of the front unit.

A zoom lens comprising in order from an object side to an image side:

• a front unit having a negative refractive power;
• and
• a rear unit having a positive refractive power, which includes an aperture stop, wherein:
• in the front unit, all distances of adjacent lenses are not variable distance, and
• the rear unit includes at least three lens units, and
• in each lens unit, all distances of adjacent lenses are not variable distance, and
• in the at least three lens units, each lens unit is disposed so that all distances of adjacent lens units are variable distance, and
• the front unit includes a first lens having a negative refractive power, a second lens having a negative refractive power, and a third lens having a positive refractive power, and
• the first lens is disposed nearest to an object, and has a meniscus shape of which a convex surface is directed toward the object side, and
• the second lens is disposed on the image side of the first lens, and has a meniscus shape of which a convex surface is directed toward the object side, and
• the rear unit includes in order from the object side to the image side, a first lens unit A and a second lens unit B, and
• at the time of zooming from a wide angle end to a telephoto end, a distance between the front unit and the rear unit narrows, and a distance between the first lens unit A and the second lens unit B changes, and
• the first lens unit A includes a focusing lens unit having a positive refractive power, which is disposed on the object side of the aperture stop, and
• at the time of focusing, only the focusing lens unit moves along an optical axis, and
• the following conditional expressions are satisfied:
• 72<VdFnmax<110,
• −1.65<FBw/fF<−0.3, and
• −2.3<fw×Fnowmin/fF<−0.7,
• where,
• vdFnmax denotes a maximum of Abbe number from among Abbe numbers for lenses having a negative refractive power in the front unit,
• FBw denotes a back focus at the wide angle end,
• fF denotes a focal length of the front unit,
• fw denotes a focal length of the overall zoom lens system at the wide angle end, and
• Fnowmin denotes a minimum of F-number from among F-numbers at the wide angle end.

A zoom lens comprising in order from an object side to an object side:

• a front unit having a negative refractive power;
• and
• a rear unit having a positive refractive power, which includes an aperture stop, wherein:
• in the front unit, all distances of adjacent lenses are not variable distance, and
• the rear unit includes at least three lens units, and
• in each lens unit, all distances of adjacent lenses are not variable distance, and
• in the at least three lens units, each lens unit is disposed so that all distances of adjacent lens units are variable distance, and
• the front unit includes a first lens having a negative refractive power, a second lens having a negative refractive power, and a third lens having a positive refractive power, and
• the first lens is disposed nearest to an object, and has a meniscus shape of which a convex surface is directed toward the object side, and
• the second lens is disposed on the image side of the first lens, and has a meniscus shape of which a convex surface is directed toward the object side, and
• the rear unit includes in order from the object side to the image side, a first lens unit A and a second lens unit B, and
• at the time of zooming from a wide angle end to a telephoto end, a distance between the front unit and the rear unit narrows, and a distance between the first lens unit A and the second lens unit B changes, and
• the first lens unit A includes a focusing lens unit having a positive refractive power, which is disposed on the object side of the aperture stop, and
• at the time of focusing, only the focusing lens unit moves along an optical axis, and
• the following conditional expressions are satisfied:
• 72<vdFnmax<110, and
• 1.25<fRw/FBw<5,
• where,
• vdFnmax denotes a maximum of Abbe number from among Abbe numbers for lenses having a negative refractive power in the front unit,
• fRw denotes a focal length of the rear unit at the wide angle end, and
• FBw denotes a back focus at the wide angle end.

A zoom lens comprising in order from an object side to an image side:

• a front unit having a negative refractive power;
• and
• a rear unit having a positive refractive power, which includes an aperture stop, wherein:
• the front unit includes a first lens having a negative refractive power, a second lens having a negative refractive power, and a third lens having a positive refractive power, and
• the first lens is disposed nearest to an object, and has a meniscus shape of which a convex surface is directed toward the object side, and
• the second lens is disposed on the image side of the first lens, and has a meniscus shape of which a convex surface is directed toward the object side, and
• the rear unit includes in order from the object side to the image side, a second lens unit having a positive refractive power which is positioned on the object side of the aperture stop, a third lens unit having a negative refractive power, and a fourth lens unit having a positive refractive power, and
• either the second lens unit or the third lens unit includes a focusing lens unit, and
• at the time of zooming from a wide angle end to a telephoto end, distances between the lens units change, and a distance between the front unit and the rear unit narrows, and
• the following conditional expressions are satisfied:
• 72<vdFnmax<110, and
• −1.45<FBw/ fF<−0.3,
• where,
• vdFnmax denotes a maximum of Abbe number from among Abbe numbers for lenses having a negative refractive power in the front unit,
• FBw denotes a back focus at the wide angle end, and
• fF denotes a focal length of the front unit.

A zoom lens comprising in order from an object side to an image side:

• a front unit having a negative refractive power;
• and
• a rear unit having a positive refractive power, which includes an aperture stop, wherein:
• the front unit includes a first lens having a negative refractive power, a second lens having a negative refractive power, and a third lens having a positive refractive power, and
• the first lens is disposed nearest to an object, and has a meniscus shape of which a convex surface is directed toward the object side, and
• the second lens is disposed on the image side of the first lens, and has a meniscus shape of which a convex surface is directed toward the object side, and
• the rear unit includes in order from the object side to the image side, a second lens unit having a positive refractive power which is positioned on the object side of the aperture stop, a third lens unit having a negative refractive power, and a fourth lens unit having a positive refractive power, and
• either the second lens unit or the third lens unit includes a focusing lens unit, and
• at the time of zooming from a wide angle end to a telephoto end, distances between the lens units change, and a distance between the front unit and the rear unit narrows, and
• the following conditional expressions are satisfied:
• 72<vdFnmax <110, and
• 1.2<fRw/FBw<5,
• where,
• vdFnmax denotes a maximum of Abbe number from among Abbe numbers for lenses having a negative refractive power in the front unit,
• fRw denotes a focal length of the rear unit at the wide angle end, and
• FBw denotes a back focus at the wide angle end.

A zoom lens comprising in order from an object side to an image side:

• a front unit having a negative refractive power;
• and
• a rear unit having a positive refractive power, which includes an aperture stop, wherein:
• the front unit includes a first lens having a negative refractive power, a second lens having a negative refractive power, and a third lens having a positive refractive power, and
• the first lens is disposed nearest to an object, and has a meniscus shape of which a convex surface is directed toward the object side, and
• the second lens is disposed on the image side of the first lens, and has a meniscus shape of which a convex surface is directed toward the object side, and
• the rear unit includes in order from the object side to the image side, a second lens unit having a positive refractive power which is positioned on the object side of the aperture stop, a third lens unit having a negative refractive power, and a fourth lens unit having a positive refractive power, and
• either the second lens unit or the third lens unit includes a focusing lens unit, and
• at the time of zooming from a wide angle end to a telephoto end, distances between the lens units change, and a distance between the front unit and the rear unit narrows, and
• the following conditional expressions are satisfied:
• 72<vdFnmax<110, and
• −1.8<fw×Fnowmin/ fF<−0.5,
• where,
• vdFnmax denotes a maximum of Abbe number from among Abbe numbers for lenses having a negative refractive power in the front unit,
• fw denotes a focal length of the overall zoom lens system at the wide angle end,
• Fnowmin denotes a minimum of F-number from among F-numbers at the wide angle end, and
• fF denotes a focal length of the front unit.