Canon Kabushiki Kaisha

Junya Ichimura

Saburo Sugawara

Masato Katayose

Makoto Takahashi

Kazuhiro Inoko

A zoom lens includes, in order from an object side to an image side, a first lens unit having a negative refractive power, a second lens unit having a positive refractive power, a third lens unit having a negative refractive power, a fourth lens unit having a negative refractive power, and a rear lens unit having a positive refractive power and disposed closest to an image plane. During zooming from a wide-angle end to a telephoto end, the second lens unit moves to the object side, and each distance between adjacent lens units changes. A predetermined condition is satisfied.

Zoom lens and image pickup apparatus

An optical system includes, in order from an object side to an image side, a front unit of a positive refractive power, a diaphragm, and a rear unit of a positive refractive power. The front unit includes, in order from the object side to the image side, a positive lens L11, a positive lens L12, and a negative lens L13. The rear unit includes, in order from the object side to the image side, a negative lens L21, a positive lens L22, and a positive lens L23. A predetermined condition is satisfied.

Optical system and image pickup apparatus having the same

Provided is a zoom lens including, from an object side to an image side: a first lens unit having a positive refractive power; a second lens unit having a negative refractive power; a third lens unit having a positive refractive power; a fourth lens unit having a negative refractive power; a fifth lens unit having a positive refractive power; a sixth lens unit having a negative refractive power; a seventh lens unit having a positive refractive power; and an eighth lens unit having a negative refractive power, in which an interval between each pair of adjacent lens units is changed for zooming.

Zoom lens, image pickup apparatus, and lens apparatus

An imaging optical system includes, in order from an enlargement conjugate side to a reduction conjugate side, a first lens unit having a positive refractive power, a second lens unit having a positive refractive power, and a third lens unit. A distance between adjacent lens units varies in focusing from a far side to a near side. An intermediate image is formed inside the second lens unit. In focusing from the far side to the near side, the second lens unit moves to the reduction conjugate side, and the third lens unit moves to the enlargement conjugate side.

Imaging optical system and image projection apparatus

A zoom lens includes, in order from an object side to an image side, a first lens unit having a positive refractive power, a second lens unit having a negative refractive power, a third lens unit having a positive refractive power, a fourth lens unit having a negative refractive power, and a rear unit having a plurality of lens units, a distance between adjacent lens units changing during zooming. A predetermined condition is satisfied.

Zoom lens and image pickup apparatus having the same

A rear attachment lens according to the aspect of the embodiments is configured to vary a focal length of a system by being attached to an image side of a master lens. The rear attachment lens includes a positive lens arranged closest to the image side in which a lens surface on the image side of the positive lens has a shape convex toward the image side. A focal length of the rear attachment lens, a magnification of the rear attachment lens when attached to the master lens, and a distance from the lens surface on the image side of the positive lens to a rear principal point position of the rear attachment lens when attached to the master lens are appropriately set.

Rear attachment lens and image pickup optical system using the same

Provided is an optical system including: a first lens unit having a positive refractive power; a second lens unit having a positive refractive power and disposed at the image side of the first lens unit; and a third lens unit having a positive refractive power and disposed closest to the image side, in which intervals between adjacent lens units are changed during focusing. The first lens unit does not move during focusing. The second lens unit moves to the object side along an optical axis during focusing from infinity to a close distance. The second lens unit includes, in order from the object side to the image side, a positive lens, a negative lens, and an aperture stop. The third lens unit includes a positive lens and a negative lens. A length of the third lens unit on the optical axis and an air-equivalent back focus are appropriately set.

Optical system and image pickup apparatus

An optical system according to the present invention is an optical system comprises a first lens unit having positive refractive power, a second lens unit having positive refractive power, and a third lens unit having negative refractive power, arranged in order from an object side to an image side. During focusing from infinity to a closest distance, the second lens unit moves to the object side, whereby a distance between adjoining lens units is changed. The second lens unit comprises an aperture stop. The following conditional expression is satisfied:1.0&#x3c;3/&#x3c;3.0,where D3 is a length of the third lens unit on an optical axis, and BF is a back focus distance.

Optical system and imaging apparatus

An optical system has a first optical axis on an incident side and a second optical axis on an exit side, and the first optical axis and the second optical axis are located at different positions. The optical system includes a reflection unit including a roof surface having a first reflection surface and a second reflection surface, and a third reflection surface parallel or orthogonal to a ridge line of the roof surface. The third reflection surface is different from the first reflection surface and the second reflection surface. The reflection unit is rotatable about the first optical axis.

Optical system and optical apparatus including the same

A zoom lens includes, in order from an enlargement conjugate side to a reduction conjugate side, a first lens unit (B) having a negative refractive power, a second lens unit (B) having a positive refractive power, a third lens unit (B) having a positive refractive power, a stop (sto), a fourth lens unit (B) having a positive refractive power, a fifth lens unit (B) having a negative refractive power, a sixth lens unit (B) having a negative refractive power, and a seventh lens unit (B) having a positive refractive power, and when zooming from a wide-angle end to a telephoto end, the second lens unit (B), the third lens unit (B), the fourth lens unit (B), the fifth lens unit (B), and the sixth lens unit (B) move from the reduction conjugate side to the enlargement conjugate side while a space between adjacent lens units changes.

Zoom lens for forming high-definition image and image projection apparatus having the same

A projection optical system includes a first lens unit that moves in a direction of an optical axis in adjusting an amount of field curvature and a second lens unit located closer to a reduction side than the first lens unit. The first lens unit includes an aspherical lens satisfying predetermined conditional equations.

Projection optical system and projection type display apparatus using the same

The imaging optical system makes magnification conjugate side and reduction conjugate side predetermined positions conjugate to each other and forms an intermediate image conjugate to both the predetermined positions. The optical system includes a magnification side positive lens as a first lens disposed on the magnification conjugate side further than an intermediate imaging position, a reduction side positive lens as a third lens disposed on the reduction conjugate side further than the intermediate imaging position, and a negative lens as a second lens disposed between these positive lenses. Conditions of 5&#x3c;&#x3bd;2&#x2212;&#x3bd;1&#x3c;80, 5&#x3c;&#x3bd;2&#x2212;&#x3bd;3&#x3c;80, 0.03&#x3c;N1&#x2212;N2&#x3c;1.0 and 0.03&#x3c;N3&#x2212;N2&#x3c;1.0 are satisfied where &#x3bd;1, &#x3bd;2 and &#x3bd;3 represent Abbe numbers of materials of the first, second and third lenses, N1, N2 and N3 represent refractive indices of the materials of the first, second and third lenses.

Imaging optical system, image projection optical system and image projection apparatus

An imaging optical system includes a first lens unit (B) having a negative refractive power configured not to move for zooming from a wide-angle end to a telephoto end, and a plurality of lens units (Bto B) configured to move so that a space between lens units adjacent to each other changes during the zooming, the first lens unit includes a first lens subunit (B) having a negative refractive power, a second lens subunit (B) having a negative refractive power, and a third lens subunit (B) having a positive refractive power, the first lens subunit (B) is configured not to move for focusing from an infinity to a close range, and the second lens subunit (B) and the third lens subunit (B) constitute a focus moving unit configured to move, during the focusing, while a space between the second and third lens subunits is narrowed.

Imaging optical system for forming high-definition image and image projection apparatus having the same

Provided is an imaging optical system including, in order from an enlargement conjugate side to a reduction conjugate side: a first lens unit having a negative refractive power; a second lens unit having a positive refractive power; a third lens unit having a positive refractive power; a fourth lens unit having a negative refractive power; and a fifth lens unit having a positive refractive power. In the imaging optical system, both of an enlargement conjugate point on the enlargement conjugate side and a reduction conjugate point on the reduction conjugate side are conjugate with an internal intermediate imaging position. The first lens unit and the fifth lens unit are stationary for focusing. The second lens unit, the third lens unit, and the fourth lens unit move on loci different from one another during the focusing.

Imaging optical system utilizing a re-imaging method and image projection apparatus including the same

A zoom lens and optical apparatus includes, in order from a magnification conjugate side, a first lens unit that has a positive refractive power and is fixed during magnification variations, and a magnification-variable unit configured to move for magnification variations. The first lens unit includes, in order from the magnification conjugate side, a first lens sub-unit that has a positive refractive power and is configured to move during focusing, and a second lens sub-unit that has a positive refractive power and moves during focusing. The first lens sub-unit and the second lens sub-unit move and reduce an interval between the first lens sub-unit and the second lens sub-unit for focusing from infinity to a close end. A surface of the second lens sub-unit closest to the magnification conjugate side has a concave shape on the magnification conjugate side.

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Utsunomiya, Japan

Junya Ichimura