A zoom lens includes, in order from an object side to an image side, a first lens unit having a negative refractive power, and a rear group having a positive refractive power as a whole including at least one lens unit. During zooming from a wide-angle end to a telephoto end, a distance between adjacent lens units changes. The first lens unit includes at least three negative single lenses, and a predetermined condition is satisfied.

Provided is an optical system and an imaging apparatus provided with the optical system. The optical system includes: a first lens having negative refractive power; a second lens having negative refractive power; a third lens having positive refractive power; and a fourth lens having positive refractive power, the first lens, the second lens, the third lens, and the fourth lens being disposed in this order from an object side. The optical system satisfies a predetermined condition relating to the focal length of the optical system and the distance on the optical axis between an exit pupil and an imaging plane in the optical system.

A zoom lens includes, in order from an object side to an image side, a first lens unit having a negative refractive power, and a rear group having a positive refractive power as a whole including at least one lens unit. During zooming from a wide-angle end to a telephoto end, a distance between adjacent lens units changes. The first lens unit includes at least three negative single lenses, and a predetermined condition is satisfied.

Provided is an optical system and an imaging apparatus provided with the optical system. The optical system includes: a first lens having negative refractive power; a second lens having negative refractive power; a third lens having positive refractive power; and a fourth lens having positive refractive power, the first lens, the second lens, the third lens, and the fourth lens being disposed in this order from an object side. The optical system satisfies a predetermined condition relating to the focal length of the optical system and the distance on the optical axis between an exit pupil and an imaging plane in the optical system.

A projection optical system projects, while enlarging, an image displayed on an image display surface and performs zooming by moving a plurality of lens groups arranged along a same optical axis. The projection optical system includes, from an enlargement side: a first lens group having a negative refractive power; a second lens group having a negative refractive power and movable during zooming; a third lens group having a positive refractive power and movable during zooming; and a lens group disposed at a most reduction-side position. The first lens group includes, from the enlargement side: a front group having a negative refractive power; and a rear group having a positive refractive power and including, from the enlargement side, a negative lens element and a positive lens element. For zooming from a wide-angle end to a telephoto end, the third lens group moves toward the enlargement side monotonically.

A projection optical system projects, while enlarging, an image displayed on an image display surface and performs zooming by moving a plurality of lens groups arranged along a same optical axis. The projection optical system includes, from an enlargement side: a first lens group having a negative refractive power; a second lens group having a negative refractive power and movable during zooming; a third lens group having a positive refractive power and movable during zooming; and a lens group disposed at a most reduction-side position. The first lens group includes, from the enlargement side: a front group having a negative refractive power; and a rear group having a positive refractive power and including, from the enlargement side, a negative lens element and a positive lens element. For zooming from a wide-angle end to a telephoto end, the third lens group moves toward the enlargement side monotonically.

A zoom lens includes, in order from an object side to an image side, a first lens unit having negative refractive power, and a rear group including at least three lens units and having combined positive refractive power at a wide-angle end. A distance between adjacent lens units changes during zooming. The first lens unit includes three negative lenses consecutively arranged from the object side to the image side. Predetermined inequalities are satisfied.