A virtual image display device includes: a first lens that has a positive refractive power and on which video light from the display element is incident, a second lens that has a positive refractive power and on which the video light passed through the first lens is incident, a prism light-guiding member that includes a first prism and a second prism, a polarized light separation film that is provided at a bonding position of the first prism and the second prism, a third lens that is disposed facing an outer surface of the first prism and that has a plano-convex shape, a transmissive mirror that is disposed on a convex surface of the third lens and that is configured to partially reflect the video light, and a quarter-wavelength plate disposed between the outer surface and the flat surface of the third lens.

A zoom lens system includes a first lens group; a second lens group; and a subsequent lens group arranged in that order from the object side. The second lens group consists of a second lens group-a, a second lens group-b, and a second lens group-c arranged in that order from the object side. A distance between the first lens group and the second lens group increases and a distance between the second lens group and the subsequent lens group decreases during a change in magnification from a short focal length end to a long focal length end. During a change in focus from infinity to a short distance, the second lens group-b is movable to the image side, and a distance between the second lens group-a and the second lens group-b and a distance between the second lens group-b and the second lens group-c are changeable.

In a zoom lens in which the interval between adjacent lens units changes during zooming, a magnification-varying lens group includes a lens group V having a negative refractive power and a lens unit C having a negative or positive refractive power. The lens group V includes a first magnification-varying lens group V1 including a lens unit V1a having a negative refractive power and a lens unit V1b having a negative refractive power. The lens units V1a and V1b move toward the image side such that the interval between the two lens units is largest at the telephoto end. The lens unit interval m1 on the optical axis between the lens units V1a and V1b at the wide angle end and the maximum lens unit interval m2 on the optical axis between the lens units V1a and V1b during zooming are set as appropriate.

An optical system includes: a first lens group having a positive refractive power, a second lens group having a negative refractive power and a third lens group having a positive or negative refractive power, arranged from an object side to an image side; when focusing, the second lens group moves along an optical axis, positions of the first and third lens groups relative to an imaging plane along the optical axis are fixed; when a lateral magnification of the third lens group at infinity is b3, a distance from a face closest to the object side of the entire optical system to the imaging plane is OAL, a focal length of the entire optical system focusing at infinity is f, and a maximum lateral magnification of the entire optical system is B, it is satisfied that: (0.80b3), (OAL/f2.00), (0.50|B|).

The zoom lens consists of, in order from an object side: a first lens group that has a positive refractive power; a middle group that includes a plurality of lens groups each moving by changing a spacing with an adjacent lens group during zooming; and a final lens group that remains stationary during zooming and has a positive refractive power. Among the plurality of lens groups that move during zooming in the middle group, an image side movable lens group, which is a lens group disposed closest to the image side, has a negative refractive power.

The zoom lens consists of, in order from an object side: a first lens group that has a positive refractive power, a middle group that includes a plurality of lens groups each moving by changing a spacing with an adjacent lens group during zooming; and a final lens group that remains stationary during zooming and has a positive refractive power. Among the plurality of lens groups that move during zooming in the middle group, an image side movable lens group, which is a lens group disposed closest to the image side, has a negative refractive power.

A zoom lens includes: a first lens group having a positive refractive power that is disposed closest to an object side; a middle group that includes a plurality of lens groups; and a final lens group that is disposed closest to an image side. All of spacings between adjacent lens groups change during changing magnification. The first lens group includes two negative lenses consecutively arranged in order from a position closest to the object side to the image side, and among the two negative lenses, a negative lens closer to the object side is a meniscus lens that has a convex surface facing the object side. The zoom lens satisfies Conditional Expression of 0.1<fw/f1<0.8 regarding a focal length f1 of the first lens group and a focal length fw of the zoom lens at a wide angle end.

A lens assembly includes a first lens group, a second lens group, and a third lens group, all of which are arranged in order from an object side to an image side along an optical axis. The first lens group is with positive refractive power and includes at least four lenses, among which the lens closest to the object side includes a convex surface facing the object side, and the lens closest to the image side includes a convex surface facing the image side. The second lens group is with negative refractive power and includes a 2-1 lens and a 2-2 lens, wherein the 2-2 lens includes a convex surface facing the image side. The third lens group is with negative refractive power and includes a 3-1 lens, wherein the 3-1 lens is a meniscus lens with negative refractive power.

A zoom lens 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, and a rear group including at least four lens units that move during zooming. Distances between adjacent lens units change during zooming. The first lens unit is fixed relative to an image plane during zooming and during focusing. The first lens unit includes at least three lenses having positive refractive powers. A predetermined condition is satisfied.

A zoom lens consists of, in order from the object side, a first lens group that has a positive refractive power, a middle group that includes a plurality of lens groups in which the spacings between adjacent lens groups change during zooming, and the final lens group. The focusing group that moves during focusing is disposed in the middle group. The zoom lens satisfies predetermined conditional expressions.