US 12,222,481 B2
Zoom lens, projection type display device, and imaging apparatus
Masaru Amano, Saitama (JP)
Assigned to FUJIFILM Corporation, Tokyo (JP)
Filed by FUJIFILM Corporation, Tokyo (JP)
Filed on Mar. 7, 2022, as Appl. No. 17/653,783.
Claims priority of application No. 2021-050782 (JP), filed on Mar. 24, 2021.
Prior Publication US 2022/0308325 A1, Sep. 29, 2022
Int. Cl. G02B 15/177 (2006.01); G02B 13/16 (2006.01); G02B 15/14 (2006.01)
CPC G02B 15/177 (2013.01) [G02B 13/16 (2013.01); G02B 15/1461 (2019.08)] 18 Claims
OG exemplary drawing
 
1. A zoom lens consisting of a first optical system and a second optical system in order from a magnification side to a reduction side along an optical path,
wherein the second optical system forms an intermediate image at a position conjugate to a reduction side imaging plane,
the first optical system reforms the intermediate image on a magnification side imaging plane,
the zoom lens includes a lens at a position closest to the magnification side on the optical path of the first optical system,
a group of which a distance to an adjacent group in an optical axis direction changes during zooming is defined as one lens group,
the second optical system includes a plurality of lens groups that move during zooming,
one of the plurality of lens groups that move during zooming is a lens group having an aperture stop that determines a numerical aperture,
the lens group having the aperture stop has a negative refractive power, and wherein
a focal length of the lens group having the aperture stop is fAp, and
a focal length of the second optical system at a wide angle end is f2w,
Conditional Expression (1) is satisfied, which is represented by
0.1<f2w/fAp<2.1  (1),
the focal length of the lens group having the aperture stop is calculated by using every surface of the lens group having the aperture stop, and
the focal length of the second optical system is calculated by using every surface of the second optical system.