JP2006221092A5 - - Google Patents

Claims (11)

In order from the object side, a first lens unit having a positive refractive power, a second lens group having a negative refractive power, and a third lens group having a positive refractive power, and in zooming from the wide-angle end state to the telephoto end state, The distance between the first lens group and the second lens group increases, the distance between the second lens group and the third lens group decreases, and the third lens group has a positive refractive power in order from the object side. It consists of a thirty-first lens group, a thirty-second lens group having a negative refractive power, and a thirty-third lens group. By moving only the thirty-second lens group in a direction orthogonal to the optical axis, the zoom lens system with a vibration reduction function that satisfies the image blur has a Oko correction, the following conditions.
−2.00 <f32 / f3 <−0.80
However,
f3 is the focal length of the third lens group,
f32 is the focal length of the thirty-second lens group. The zoom lens having an image stabilization function according to claim 1, wherein the following condition is satisfied.
1.40 <f1 / fw <2.00
−0.53 <f2 / fw <−0.32.
0.35 <f3 / fw <0.65
− 0.20 <f3 / f33 <0.50
However,
fw is the focal length of the zoom lens in the wide-angle end state,
f1 is the focal length of the first lens group,
f2 is the focal length of the second lens group,
f3 is the focal length of the third lens group ,
f33 is the focal length of the 33rd lens group Angle end state to the telephoto end state, the zoom lens system with a vibration reduction function according to claim 1 or 2, wherein the first lens and the third lens group and group thus being moved toward the object . The thirty-first lens group has at least three positive lenses and at least one negative lens, the thirty-second lens group has at least one positive lens and at least one negative lens, and the thirty-third lens. the zoom lens system with a vibration reduction function according to any one of claims 1 to 3 group, characterized in that it comprises at least one negative lens and at least one positive lens. The thirty-first lens group includes, in order from the object side, a first cemented lens including a biconvex positive lens, a biconvex positive lens and a negative lens having a concave surface facing the object side, and a convex surface facing the object side. and a positive meniscus lens, a second cemented lens, a zoom lens having a vibration reduction function according to claim 1, any one of 4 which satisfies the following conditions.
0.20 <n31N-n31P
30.0 <ν31P-ν31N
However,
n31N is the refractive index of the negative lens in the first cemented lens,
n31P is the refractive index of the biconvex positive lens in the first cemented lens,
ν31N is the Abbe number with respect to the d-line (wavelength 587.6 nm) of the negative lens in the first cemented lens,
ν31P is the Abbe number with respect to the d-line (wavelength: 587.6 nm) of the biconvex positive lens in the first cemented lens The 32nd lens unit includes, in order from the object side, a positive lens having a convex surface directed toward the image side has a biconcave negative lens, of claims 1 to 5, characterized in that the following condition is satisfied A zoom lens having an image stabilization function according to any one of the preceding claims.
10.0 <ν32N−ν32P
However,
ν32N is the Abbe number for the d-line (wavelength 587.6 nm) of the biconcave negative lens in the thirty-second lens group,
ν32P is the Abbe number for the d-line (wavelength 587.6 nm) of the positive lens in the thirty-second lens group. The 32nd lens unit includes, in order from the object side and a positive lens and a double concave negative lens of the cemented lens having a convex surface directed toward the image side, claim 1, characterized by satisfying the following condition 6 A zoom lens having the image stabilization function according to any one of the above.
−2.00 <(r32R + r32F) / (r32R−r32F) <− 0.70
However,
r32F is a radius of curvature of the object side surface of the positive lens of the thirty-second lens group,
r32R is the radius of curvature of the image side surface of the biconcave negative lens of the thirty-second lens group The zoom lens having an image stabilization function according to claim 7, wherein the following condition is satisfied.
0.40 <r32S / f32 <0.90
However,
r32S is a radius of curvature of the cemented surface of the cemented lens of the thirty-second lens group,
f32 is the focal length of the thirty-second lens group. The first lens group, the second lens group, and the zoom lens system with a vibration reduction function according to any one of claims 1 to 8, characterized in that it consists of only the third lens group. The first lens group includes, in order from the object side, an eleventh lens group having a positive refractive power and a twelfth lens group having a positive refractive power. In focusing from a long distance state to a short distance state, the twelfth lens group only moved toward the object, a zoom lens having a vibration reduction function according to any one of claims 1 9, characterized in that the following condition is satisfied.
1.70 <f11 / f12 <4.00
However,
f11 is a focal length of the eleventh lens group,
f12 is the focal length of the twelfth lens group   The zoom lens according to any one of claims 1 to 6, wherein the thirty-second lens group includes a cemented lens.