Canon Kabushiki Kaisha

Koji Hoshi

Makoto Sekita

Norihiro Nanba

Hiroyuki Hamano

Kazuo Fujibayashi

Yoshihiro Ishibe

Manabu Kato

Takeshi Koyama

Takeshi B Nishimura

An image-taking apparatus is disclosed which is capable of adjusting a positional displacement of an image-taking optical system and an image-pickup element even in a state in which they are fixed. The image-taking apparatus includes the image-taking optical system including an offset lens unit movable in a direction orthogonal to an optical axis, the image-pickup element and a memory which stores adjustment data. The adjustment data is data on a movement amount of the offset lens unit to make light amounts in peripheral parts on the image-pickup element substantially homogeneous in a case where an object has a surface with approximately homogeneous luminance.

Image-taking apparatus capable of preventing an object point from moving orthogonal to the optical axis during magnification

A zoom lens comprises, from object to image side: a positive first-lens unit; a negative second-lens unit; a positive third-lens unit; and a positive fourth-lens unit; the third-lens unit comprising a negative 3a'th-lens sub-unit and positive 3b&#x2032;th-lens sub-unit from object side; the second-lens unit and fourth-lens unit moving on the optical axis during zooming; the 3b&#x2032;th-lens sub-unit moving in a direction perpendicular to the optical axis, thereby displacing an image perpendicular to the optical axis; the 3a&#x2032;th-lens sub-unit comprising a negative-lens element Gwhose both surfaces are spherical, and a positive-lens element whose both surfaces are spherical; the 3b&#x2032;th-lens sub-unit including a positive-lens element Gincluding an aspherical lens surface, and a negative-lens element; wherein, assuming that the indices of the materials of the negative-lens element Gand the positive-lens element Gare NGand NGrespectively, 0.21&#x3c;NG&#x2212;NGis satisfied.

Zoom lens and image pickup apparatus including the same

Provided is a zoom lens system which includes a plurality of lens units separated from one another at intervals changed during at least one of zooming and focusing and an aperture stop. The plurality of lens units include a movable lens unit for displacing an image formed by the zoom lens system within a plane perpendicular to an optical axis. The movable lens unit includes a first lens subunit located on an object side of the aperture stop and a second lens subunit located on an image side of the aperture stop. When the image formed by the zoom lens system is displaced within the plane perpendicular to the optical axis, the aperture stop is held and the first lens subunit and the second lens subunit are moved to have a component in a direction orthogonal to the optical axis.

Zoom lens system and image pickup apparatus including the same

A zoom lens comprises, from object to image side: a positive first-lens unit; a negative second-lens unit; a positive third-lens unit; and a positive fourth-lens unit; the third-lens unit comprising a negative 3a'th-lens sub-unit and positive 3b'th-lens sub-unit from object side; the second-lens unit and fourth-lens unit moving on the optical axis during zooming; the 3b'th-lens sub-unit moving in a direction perpendicular to the optical axis, thereby displacing an image perpendicular to the optical axis; the 3a'th-lens sub-unit comprising a negative-lens element G3an whose both surfaces are spherical, and a positive-lens element whose both surfaces are spherical; the 3b'th-lens sub-unit including a positive-lens element G3bp including an aspherical lens surface, and a negative-lens element; wherein, assuming that the indices of the materials of the negative-lens element G3an and the positive-lens element G3bp are NG3an and NG3bp respectively, 0.21&#x3c;NG3an&#x2212;NG3bp is satisfied.

A zoom lens system, in that order from an object side to an image side, includes first to fourth lens units respectively having positive, negative, positive, and positive optical powers. The second and fourth lens units move along an optical axis during zooming. In the zoom lens system, the third lens unit includes a first lens subunit having a negative optical power, and a second lens subunit having a positive optical power, in that order from the object side to the image side. The first lens subunit has no more than a positive lens element and a negative lens element. The second lens subunit has no more than a positive lens element and a negative lens element. Accordingly, the arrangements of the third lens unit and other lens units are properly set.

Zoom lens system and camera having the same

A zoom lens includes: a first lens unit of positive refractive power; a second lens unit of negative refractive power; a third lens unit of positive refractive power; and a fourth lens unit of positive refractive power, being disposed in that order from an object side to an image side, in which the second and fourth lens units are moved in a direction parallel with an optical axis of the zoom lens during zooming, the first lens unit consists of one negative lens and three or fewer positive lenses, being disposed in that order from the object side to the image side, and the following condition is satisfied:25.1&#x3c;1/2&#x3c;4.1&#xd7;where BD1 and BD2 are lengths of the first and second lens units along the optical axis, and Z is a zoom ratio.

Zoom lens and image pickup apparatus having the same

A zoom lens, including, in order from an object side to an image side (a) a first lens unit of negative optical power, (b) a second lens unit of positive optical power, and (c) a third lens unit of positive optical power, wherein a separation between the first lens unit and the second lens unit and a separation between the second lens unit and the third lens unit are varied to effect variation of magnification, and wherein the zoom lens satisfies the following conditions: ndp3&#x3c;1.5 and &#x3bd;dp3&#x3e;70.0, where ndp3 and &#x3bd;dp3 are a refractive index and Abbe number, respectively, of material of the positive lens in the third lens unit.

Zoom lens and optical apparatus having the same

Image-taking apparatus and optical adjustment method for an image-taking apparatus with displacement of the optical axis

A zoom lens system is disclosed, comprising, in order from an object side to an image side, a first lens unit with a positive refractive power, a second lens unit with a negative refractive power, a third lens unit with a positive refractive power, and a fourth lens unit with a positive refractive power, wherein a distance between the respective lens units is changed during zooming. The third lens unit consists of, in order from the object side to the image side, a first lens sub-unit including a positive lens with an object-side surface which has a convex shape and having a positive refractive power, an aperture stop, a second lens sub-unit including a negative lens and having a negative optical power, and a third lens sub-unit including a positive lens and having a positive optical power.

Zoom lens system and image-taking apparatus having the same

A zoom lens, comprising, in order from an object side to an image side: (a) a first lens unit of negative optical power; (b) a second lens unit of positive optical power; and (c) a third lens unit of positive optical power, wherein a separation between the first lens unit and the second lens unit and a separation between the second lens unit and the third lens unit are varied during zooming, and wherein, during zooming from a wide-angle end to a telephoto end, the first lens unit moves so that its motion comprises (a) moving toward the image side and (b) moving thereafter toward the object side, and the third lens unit moves so that its motion comprises (a) moving toward the image side and (b) moving thereafter toward the object side.

A zoom lens, including, in order from an object side to an image side (a) a first lens unit of negative optical power, (b) a second lens unit of positive optical power, and (c) a third lens unit of positive optical power, wherein a separation between the first lens unit and the second lens unit and a separation between the second lens unit and the third lens unit are varied to effect variation of magnification, and wherein, during the variation of magnification from a wide-angle end to a telephoto end with an infinitely distant object focused on, the third lens unit moves monotonically toward the image side or moves with a locus convex toward the image side.

A zoom lens, including, in order from an object side to an image side (a) a first lens unit of negative optical power, (b) a second lens unit of positive optical power, and (c) a third lens unit of positive optical power, wherein a separation between the first lens unit and the second lens unit and a separation between the second lens unit and the third lens unit are varied to effect variation of magnification, and wherein the zoom lens satisfies the following conditions: ndp&#x3c;1.5 and vdp&#x3e;70.0, where ndpand vdpare a refractive index and Abbe number, respectively, of material of the positive lens in the third lens unit.

A zoom lens includes a first lens unit which does not move for zooming and has positive optical power, a second lens unit having negative optical power, a third lens unit having positive optical power, and a fourth lens unit having positive optical power, these lens unit being arranged in order from the object side to the image side. Due to this simple construction, it is possible to obtain high optical performance over the entire object distance from an object at infinity to a nearby object.

Zoom lens and camera with the zoom lens

An optical apparatus includes a photographic optical unit including a movable optical component for varying a focal length, a light amount adjusting unit disposed in an optical path of the photographic optical unit, the light amount adjusting unit varying an aperture to adjust an amount of light and changing an F-number by varying the aperture, an image pickup device for picking up an optical image formed by the photographic optical unit, a mode switching member for selecting a dynamic image taking mode and a static image taking mode, and a controller. The controller sets different values of the F-number of the light amount adjusting unit in accordance with a state selected by the mode switching member, or varies a moving range of the movable optical component in accordance with a state selected by the mode switching member.

Growing community of inventors

Utsunomiya, Japan

Koji Hoshi