Canon Kabushiki Kaisha

Suguru Inoue

Shinichiro Saito

Shigenobu Sugita

Takahiro Hatada

Satoshi Maetaki

Shunji Iwamoto

Yuichi Gyoda

Makoto Nakahara

Akira Mizuma

Masakazu Yamagishi

Yuki Nagao

An optical system includes a first lens unit having positive refractive power, a second lens unit, and a third lens unit having negative refractive power arranged in order from an object side to an image side. The second lens unit moves in focusing, thereby changing a distance between adjacent lens units. The first lens unit includes a positive lens, and the third lens unit includes a negative lens. A focal length of the positive lens, a focal length of the negative lens, a focal length of the third lens unit, and a back focus of the optical system are appropriately set.

Optical system and imaging apparatus including the same

An optical system is constituted of a first lens unit having a positive refractive power, a second lens unit having a positive refractive power and moving when focusing is performed, and a third lens unit which are arranged in this order from an object side to an image side, and distances between neighboring lens units are changed when focusing is performed. In the optical system, a back focus, arrangement of the second lens unit, and the like are appropriately set.

Optical system and image capturing apparatus including the same

An optical system includes a first lens unit Bhaving a positive refractive power, a second lens unit B, and a third lens unit Bdisposed in order from an object side to an image side. The second lens unit Bmoves in focusing so that an interval between adjacent lens units among the first, second, and third lens units changes. The first lens unit Bincludes a positive lens Gdisposed closest to the object side and a negative lens Gbeing a closest negative lens with respect to the object side. The optical system satisfies a predetermined condition.

An optical system used in an imaging apparatus includes an optical element. In a case where the optical element is disposed on a magnification side with respect to an intersection point of an optical axis and a chief paraxial ray, the optical element is a negative lens, and in a case where the optical element is disposed on a reduction side with respect to the intersection point, the optical element is a positive lens. The optical element is configured to satisfy all of the following conditional expressions:30&#x2264;&#x3bd;&#x2264;401.225&#x2264;[&#x2212;(14.387/&#x3bd;)]&#x2264;1.2760.4300&#x2264;[&#x3b8;&#x2212;(2.9795/&#x3bd;)]&#x2264;0.5010,where &#x3bd;d represents an Abbe number of the optical element, &#x3b8;gF is a partial dispersion ratio of the optical element for g-line and F-line, and nd is a refractive index of the optical element for d-line.

Optical system and optical apparatus including the same

An optical system includes a first lens unit that has a positive refractive power; a second lens unit that is arranged to move during focusing and has a positive or negative refractive power; and a third lens unit that has a positive or negative refractive power. The first lens unit, the second lens unit, and the third lens unit are disposed in that order from an object side to an image side. During the focusing, an interval between adjacent lens units changes. In the optical system, a focal length f of the entire optical system, a distance LD along an optical axis from a lens surface of the first lens unit that is closest to the object side to an image plane, a material of positive lenses included in the first lens unit, and an arrangement of the positive lenses included in the first lens unit are appropriately set.

Optical system and image pickup apparatus including the same

A lens apparatus that includes an optical system including a positive lens, the lens apparatus including a holding member arranged to hold the positive lens, an exterior member arranged to accommodate the holding member, and an engaging mechanism arranged to engage the holding member and the exterior member to each other.

Lens apparatus and an image pickup apparatus including same

An optical system includes a plurality of lenses. The distance from the object side lens surface of a lens arranged an the most object side to the image plane is longer than the focal length of the entire system. The material of a positive lens Garranged on the most object side among positive lenses included in the optical system, and the arrangement and material of a negative lens Gn located on the most object side among negative lenses arranged an the image side of the positive lens Gare appropriately set.

Optical system and image pickup apparatus having the same

In an optical system which includes a positive lens Gp and in which a distance on an optical axis from an object-side lens surface of a lens disposed closest to an object side to an image surface is shorter than a focal length of an entire system, an arrangement and a material of the positive lens Gp, and an arrangement of a focus unit are set appropriately.

An optical system includes a negative lens satisfying the following conditional expressions:30&#x2264;&#x3bd;&#x2264;40,1.225&#x2264;[&#x2212;(14.387/&#x3bd;)]&#x2264;1.276, and0.4300&#x2264;[&#x3b8;&#x2212;(2.9795/&#x3bd;)]&#x2264;0.5010,where &#x3bd;d is an Abbe number of the negative lens, &#x3b8;gF is a partial dispersion ratio of the negative lens at a g-line and an F-line, and nd is a refractive index of the negative lens at a d-line.

A conversion lens having a negative refractive power includes a positive lens GP. The positive lens GP satisfies all the following conditional expressions:30&#x2264;&#x3bd;&#x2264;40,1.225&#x2264;[&#x2212;(14.387/&#x3bd;)]&#x2264;1.276, and0.4300&#x2264;[&#x3b8;&#x2212;(2.9795/&#x3bd;)]&#x2264;0.5010,where &#x3bd;d is an Abbe number of the positive lens GP, &#x3b8;gF is a partial dispersion ratio of the positive lens GP for g-line and F-line, and nd is a refractive index of the positive lens GP for d-line.

Conversion lens, and imaging optical system and optical apparatus including conversion lens

Provided is a zoom lens, including, in order from an object side to an image side: a first lens unit to a fourth lens unit having negative, positive, negative, and negative refractive powers; and a rear lens group. In the zoom lens, an interval between each pair of adjacent lens units is changed during zooming, the rear lens group has a positive refractive power over an entire zoom range, the third lens unit is configured to move in an optical axis direction during focusing, and each of a focal length of the zoom lens at a wide angle end (fw), and a focal length of the third lens unit (f3) is appropriately set.

Zoom lens and image pickup apparatus including the same

An optical system includes an optical element. When the optical element is disposed on a magnification side with respect to an intersection point between an optical axis and a chief paraxial ray, the optical element is a positive lens. When the optical element is disposed on a reduction side with respect to the intersection point, the optical element is a negative lens. The optical element satisfies all of the following conditional expressions:30&#x2264;&#x3bd;&#x2264;401.225&#x2264;[&#x2212;(14.387/&#x3bd;)]&#x2264;1.2760.4300&#x2264;[&#x3b8;&#x2212;(2.9795/&#x3bd;)]&#x2264;0.5010where &#x3bd;d is Abbe number of the optical element, &#x3b8;gF is a partial dispersion ratio of the optical element for g-line and F-line, and nd is a refractive index of the optical element for d-line.

An optical system includes a first lens unit that has positive refractive power, a second lens unit that moves during focusing and that has positive refractive power or negative refractive power, and a third lens unit that has positive refractive power or negative refractive power. The first lens unit, the second lens unit, and the third lens unit are disposed in that order from an object side to an image side. During focusing, an interval between adjacent lens units changes. In the optical system, a focal length f of the entire optical system, a distance LD along an optical axis from a lens surface of the first lens unit that is closest to the object side to an image plane, and focal lengths of positive and negative lenses that are included in the first lens unit are appropriately set.

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Utsunomiya, Japan

Suguru Inoue