Composite optical element and optical system including the same
A composite optical element includes a glass lens and a resin lens that are joined together. The resin lens has an aspheric shape. When Nd is a refractive index of the resin lens, νd is an Abbe number of the resin lens, and θgF is a partial dispersion ratio of the resin lens, Nd, νd, and θgF are appropriately set.
1 . An optical system comprising:
a composite optical element including a glass lens and a resin lens that are joined together,
wherein the resin lens has an aspheric shape,
wherein the optical system includes a first lens unit having a positive refractive power, a second lens unit having a negative refractive power, a third lens unit having a positive refractive power, and a rear group that are arranged in that order from an object side to an image side, the rear group including at least one lens unit,
wherein intervals between the lens units that are adjacent to each other vary during zooming,
wherein the composite optical element is disposed on the image side of the first lens unit, and
wherein, when Nd is a refractive index of the resin lens, vd is an Abbe number of the resin lens, and θgF is a partial dispersion ratio of the resin lens, the following inequalities are satisfied:
1.900< Nd +(0.014× vd )<2.045
30.0< vd< 35.0
0.6200< θgF +(0.0024× vd )<0.6900.
2 . The optical system according to claim 1 , wherein the composite optical element is disposed closest to the object side in the second lens unit.
3 . The optical system according to claim 1 , wherein the rear group includes a fourth lens unit disposed closest to the object side, and
wherein the composite optical element is included in the fourth lens unit.
4 . An optical system according to claim 1 comprising:
a composite optical element including a glass lens and a resin lens that are joined together,
wherein the resin lens has an aspheric shape,
wherein the optical system includes a first lens unit having a negative refractive power, a second lens unit having a positive refractive power, and a rear group that are arranged in that order from an object side to an image side, the rear group including at least one lens unit,
wherein intervals between the lens units that are adjacent to each other vary during zooming, and
wherein the composite optical element is included in the first lens unit, and
wherein, when Nd is a refractive index of the resin lens, vd is an Abbe number of the resin lens, and θgF is a partial dispersion ratio of the resin lens, the following inequalities are satisfied:
1.900< Nd +(0.014× vd )<2.045
30.0< vd< 35.0
0.6200< θgF +(0.0024× vd )<0.6900.
5 . An optical system, comprising:
a composite optical element including a glass lens and a resin lens that are joined together,
wherein the resin lens has an aspheric shape,
wherein the optical system includes a first lens unit having a negative refractive power, a second lens unit having a positive refractive power, and a rear group that are arranged in that order from an object side to an image side, the rear group including at least one lens unit,
wherein intervals between the lens units that are adjacent to each other vary during zooming, and
wherein the composite optical element is included in the second lens unit, and
wherein, when Nd is a refractive index of the resin lens, vd is an Abbe number of the resin lens, and θgF is a partial dispersion ratio of the resin lens, the following inequalities are satisfied:
1.900< Nd +(0.014× vd )<2.045
30.0< vd< 35.0
0.6200< θgF +(0.0024× vd )<0.6900.
6 . An optical system comprising:
a composite optical element including a glass lens and a resin lens that are joined together,
wherein the resin lens has an aspheric shape,
wherein the optical system includes a first lens unit having a negative refractive power, a second lens unit having a positive refractive power, a third lens unit having a negative refractive power, and a rear group that are arranged in that order from an object side to an image side, the rear group including at least one lens unit,
wherein intervals between the lens units that are adjacent to each other vary during zooming,
wherein the composite optical element is included in the third lens unit, and
wherein, when Nd is a refractive index of the resin lens, vd is an Abbe number of the resin lens, and θgF is a partial dispersion ratio of the resin lens, the following inequalities are satisfied:
1.900< Nd +(0.014× vd )<2.045
30.0< vd< 35.0
0.6200< θgF +(0.0024× vd )<0.6900.
7 . An imaging apparatus comprising:
an optical system; and
an image pickup device that receives an image formed by the optical system,
wherein the optical system includes:
a composite optical element including a glass lens and a resin lens that are joined together,
wherein the resin lens has an aspheric shape,
wherein the optical system includes a first lens unit having a positive refractive power, a second lens unit having a negative refractive power, a third lens unit having a positive refractive power, and a rear group that are arranged in that order from an object side to an image side, the rear group including at least one lens unit,
wherein intervals between the lens units that are adjacent to each other vary during zooming,
wherein the composite optical element is disposed on the image side of the first lens unit, and
wherein, when Nd is a refractive index of the resin lens, vd is an Abbe number of the resin lens, and θgF is a partial dispersion ratio of the resin lens, the following inequalities are satisfied:
1.900< Nd +(0.014× vd )<2.045
30.0< vd< 35.0
0.6200< θgF +(0.0024× vd )<0.6900.