Magnification optical system
AssigneeRicoh Company, Ltd.
InventorsHibiki TATSUNO, Kiichiro Nishina, Yasuyuki Shibayama, Takanobu Osaka, Makoto Hirakawa
Life of this patent
Estimating the term…
Abstract
A magnification optical system forms an enlarged image of an object. It includes a refractive optical system including a plurality of lens groups; and a mirror train including a curved mirror, arranged in this order from an object side, a first focus structure configured to move the respective lens groups of the refractive optical system by different amounts along a normal line of a conjugate surface on the object side, and a second focus structure configured to move the respective lens groups along the normal line of the conjugate surface on the object side by different amounts from those of the first focus structure.
Claims15
(canceled)
A magnification optical system that enlarges an image of an object, the magnification optical system comprising:
- a refractive optical system including, in order from an object side to an enlarged side,
- a first lens group having a positive power,
- a second lens group,
- a third lens group including a plurality of lenses, and
- a fourth lens group;
- a curved mirror that reflects light from the refractive optical system;
- and
- a focus structure that moves the third lens group and the fourth lens group and does not move the first lens group and the curved mirror.
A magnification optical system that enlarges an image of an object, the magnification optical system comprising:
- a first optical system including a plurality of lens groups;
- a second optical system including a curved mirror that reflects light received from the first optical system;
- and
- a focus structure that moves a part of the plurality of lens groups of the first optical system, wherein
- the plurality of lens groups includes, in order from an object side to an enlarged side,
- a first lens group,
- a second lens group,
- a third lens group, and
- a fourth lens group, and
- the focus structure moves the third lens group and the fourth lens group, and does not move the first lens group and the curved mirror, to change an interval between the fourth lens group and the third lens group.
Dependencies are inferred from the claim text.