An optical imaging system includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens sequentially disposed in ascending numerical order along an optical axis from an object side of the optical imaging system toward an imaging plane of the optical imaging system. Four or more lenses among the first to seventh lenses have a refractive index greater than 1.6.

A zoom lens includes a negative first lens group, a positive second lens group, and a subsequent lens group in order from an object side. A focusing lens group closer to an image side than the first lens group moves during focusing. The first lens group consists of a first-a lens group and a first-b lens group in order from the object side. Assuming that an average of refractive indices of the negative lenses of the first-a lens group is Nd1ave, a focal length of the focusing lens group is ff, and a focal length of the first lens group is f1, Conditional Expression (1) of 1.73<Nd1ave<1.95 and Conditional Expression (2) of 1<|ff/f1|<3 are satisfied.

A zoom lens includes a negative first lens group, a positive second lens group, and a subsequent lens group in order from an object side. A focusing lens group closer to an image side than the first lens group moves during focusing. The first lens group consists of a first-a lens group and a first-b lens group in order from the object side. Assuming that an average of refractive indices of the negative lenses of the first-a lens group is Nd1ave, a focal length of the focusing lens group is ff, and a focal length of the first lens group is f1, Conditional Expression (1) of 1.73<Nd1ave<1.95 and Conditional Expression (2) of 1<|ff/f1|<3 are satisfied.

The present disclosure discloses an imaging apparatus and an electronic device. The imaging apparatus includes a macro lens group, a wide-angle lens group, and a telephoto lens group. An effective focal length f.sub.A of the macro lens group, an effective focal length f.sub.B of the wide-angle lens group and an effective focal length f.sub.C of the telephoto lens group satisfy: f.sub.A<f.sub.B<f.sub.C, 0.20<f.sub.A/f.sub.B<0.80 and 0.10<f.sub.A/f.sub.C<0.50.

The present disclosure discloses an imaging apparatus and an electronic device. The imaging apparatus includes a macro lens group, a wide-angle lens group, and a telephoto lens group. An effective focal length f.sub.A of the macro lens group, an effective focal length f.sub.B of the wide-angle lens group and an effective focal length f.sub.C of the telephoto lens group satisfy: f.sub.A<f.sub.B<f.sub.C, 0.20<f.sub.A/f.sub.B<0.80 and 0.10<f.sub.A/f.sub.C<0.50.

A zoom lens consists of, in order from an object side to an image side, a first lens unit having a negative refractive power, a second lens unit having a positive refractive power, and a rear group including one or more lens units. Each distance between adjacent lens units changes during zooming. The rear group includes a focus lens unit having a positive refractive power that moves from the image side to the object side during focusing from an infinite distance object to a close distance object. A lens closest to an object in the focus lens unit has a shape with a concave surface on the object side. The following inequalities are satisfied.

1.20<fLP/fL2<3.20

−3.00<fL1/fL2<−0.85

fLP represents a focal length of the focus lens unit, fL1 represents a focal length of the first lens unit, and fL2 represents a focal length of the second lens unit.

A zoom lens consists of, in order from an object side to an image side, a first lens unit having a negative refractive power, a second lens unit having a positive refractive power, and a rear group including one or more lens units. Each distance between adjacent lens units changes during zooming. The rear group includes a focus lens unit having a positive refractive power that moves from the image side to the object side during focusing from an infinite distance object to a close distance object. A lens closest to an object in the focus lens unit has a shape with a concave surface on the object side. The following inequalities are satisfied.

1.20<fLP/fL2<3.20

−3.00<fL1/fL2<−0.85

fLP represents a focal length of the focus lens unit, fL1 represents a focal length of the first lens unit, and fL2 represents a focal length of the second lens unit.

A zoom lens includes, in order from an object side to an image side, a first lens unit having negative refractive power, a second lens unit having positive refractive power, and a rear unit including one or more lens units. A distance between adjacent lens units changes during zooming. The rear unit includes a focus lens unit having positive refractive power and configured to move from the image side to the object side during focusing from infinity to a short-distance end. The first lens unit includes, in order from the object side to the image side, a first negative lens and a second negative lens. A predetermined condition is satisfied.

A zoom lens includes, in order from an object side to an image side, a first lens unit having negative refractive power, a second lens unit having positive refractive power, and a rear unit including one or more lens units. A distance between adjacent lens units changes during zooming. The rear unit includes a focus lens unit having positive refractive power and configured to move from the image side to the object side during focusing from infinity to a short-distance end. The first lens unit includes, in order from the object side to the image side, a first negative lens and a second negative lens. A predetermined condition is satisfied.

An optical system includes, in order from an object side to an image side, a first lens unit having positive refractive power, a second lens unit having negative refractive power, a third lens unit having positive or negative refractive power, a fourth lens unit having positive refractive power, and a fifth lens unit having negative refractive power. During focusing from infinity to the shortest distance, the second lens unit and the fourth lens unit move, the first lens unit, the third lens unit, and the fifth lens unit do not move. A predetermined condition is satisfied.