Abstract: An image-taking lens unit includes: a variable magnification optical system for forming an optical image of an object with a variable magnification; and an image sensor for converting the optical image into an electrical signal. The image-taking lens unit changes the shape thereof between a photographing state and a non-photographing state. The variable magnification optical system has a plurality of lens groups for performing magnification variation by changing intervals therebetween and a reflective surface for bending an optical axis. At least one of the plurality of lens groups is a movable group that moves during magnification variation. The reflective surface is kept in fixed position during magnification variation or focusing. In transition from the photographing state to the non-photographing state, at least the reflective surface moves so that at least part of the movable group is stored into a space left after the movement of the reflective surface.

Abstract: A magnification varying optical system that directs light from an object to an image sensor includes in order from the object side: a first lens unit having negative optical power and including an optical axis changing element that changes the optical axis; a second lens unit having positive optical power and including three lens elements; a third lens unit having negative optical power; and a fourth lens unit having positive optical power. In this magnification varying optical system, in magnification varying from the wide-angle end to the telephoto end, the first lens unit is stationary, the distance from the first lens unit to the second lens unit decreases, and the distance from the third lens unit to the fourth lens unit increases. The magnification varying optical system satisfies the specified conditions.

Abstract: A taking lens apparatus includes a zoom lens system that is composed of a plurality of lens units and that achieves zooming by varying the distances between the lens units and an image sensor that converts the optical image formed by the zoom lens system into an electrical signal. The zoom lens system has, from the object side,: a first lens unit having a negative optical power, a second lens unit disposed on the image side of the first lens unit and having a negative optical power, a third lens unit disposed on the image side of the second lens unit and having a positive optical power, a fourth lens unit disposed on the image side of the third lens unit and having a positive optical power, and a fifth lens unit disposed on the image side of the fourth lens unit and having a positive optical power. During zooming, the first lens unit remains stationary relative to the image sensor, and the second and third lens units move.

Abstract: A variable magnification optical system for forming an optical image of an object onto a light acceptance surface of an image sensor, has in order from an object side: a first lens group having negative optical power; a second lens group having positive optical power; and a third lens group having positive optical power, the third lens group including at least two lenses. In magnification change from a wide-angle limit to a telephoto limit, the first lens group moves along a locus convex to an image side, the second lens group moves monotonically to the object side, and the third lens group moves along a locus convex to the object side.

Abstract: A variable magnification optical system of the present invention for forming an optical image of an object on a light-receiving surface of an image sensor with variable magnification includes: from the object side, at least a first lens unit having a positive optical power, a second lens unit having a negative optical power, a third lens unit having a positive optical power, and a fourth lens unit having a positive optical power. The variable magnification is performed by movement of at least the first lens unit and the third lens unit. A bending optical element for bending an optical axis is provided between the second lens unit and the third lens unit. Moreover, prescribed conditional formulae are fulfilled.

Abstract: An object of the present invention is to provide a compact size variable power optical system capable of producing a high quality image. The variable power optical system comprises a plurality of lens groups for forming an optical image on an image surface of an image pickup device. Among the plurality of lens groups, the first lens group, which is disposed in the most subject side has a negative refraction power, includes at least a lens having a negative refraction power and a reflective optical element for bending the optical axis. When varying the variable power, the axial distance between the first lens group and the image surface varies. When Nd denotes the refraction power of the lens having negative refraction power at d-line, the refraction power satisfies the conditional formula Nd>1.81.

Abstract: A compact bent zooming imaging optical system characterized by sufficient aberration correction. The imagining optical system contains, in order from the object, a first lens group having positive refractive power, a second lens group with negative power which has a reflective optical element for bending the optical axis and lenses on each of the object side and the image side of the reflective optical element, and a following lens group. At least the aforementioned first lens group and following lens group are moved to change in the magnification. ?0.6<?1/?2<?0.15 is satisfied wherein ?1 denotes the refractive power of the first lens group and ?2 indicates the refractive power of the second lens group.

Abstract: A magnification varying optical system that directs light from an object to an image sensor includes in order from the object side: a first lens unit having negative optical power and including an optical axis changing element that changes the optical axis; a second lens unit having positive optical power and including three lens elements; a third lens unit having negative optical power; and a fourth lens unit having positive optical power. In this magnification varying optical system, in magnification varying from the wide-angle end to the telephoto end, the first lens unit is stationary, the distance from the first lens unit to the second lens unit decreases, and the distance from the third lens unit to the fourth lens unit increases. The magnification varying optical system satisfies the specified conditions.

Abstract: An imaging optical unit including a simple and small retracting mechanism and optical members having a small eccentric error and an image pickup apparatus will be provided. The imaging optical unit for guiding light to an image pickup device is structured so that a first holding member, for holding a reflection member for turning a light flux entering from the side of a subject along a first optical axis to a second optical axial direction almost at right angle, rotates freely about a rotating shaft between the retracting position where the first holding member is housed in a lens frame of the imaging optical unit and the using position where it is projected.

Abstract: A variable magnification optical system for forming an optical image of an object onto a light acceptance surface of an image sensor, has in order from an object side: a first lens group having negative optical power; a second lens group having positive optical power; and a third lens group having positive optical power, the third lens group including at least two lenses. In magnification change from a wide-angle limit to a telephoto limit, the first lens group moves along a locus convex to an image side, the second lens group moves monotonically to the object side, and the third lens group moves along a locus convex to the object side.

Abstract: A compact bent zooming imaging optical system characterized by sufficient aberration correction. The imagining optical system contains, in order from the object, a first lens group having positive refractive power, a second lens group with negative power which has a reflective optical element for bending the optical axis and lenses on each of the object side and the image side of the reflective optical element, and a following lens group. At least the aforementioned first lens group and following lens group are moved to change in the magnification. ?0.6<?1/?2<?0.15 is satisfied wherein ?1 denotes the refractive power of the first lens group and ?2 indicates the refractive power of the second lens group.

Abstract: An image-taking lens unit includes: a variable magnification optical system for forming an optical image of an object with a variable magnification; and an image sensor for converting the optical image into an electrical signal. The image-taking lens unit changes the shape-thereof between a photographing state and a non-photographing state. The variable magnification optical system has a plurality of lens groups for performing magnification variation by changing intervals therebetween and a reflective surface for bending an optical axis. At least one of the plurality of lens groups is a movable group that moves during magnification variation. The reflective surface is kept in fixed position during magnification variation or focusing. In transition from the photographing state to the non-photographing state, at least the reflective surface moves so that at least part of the movable group is stored into a space left after the movement of the reflective surface.

Abstract: An imaging optical unit including a simple and small retracting mechanism and optical members having a small eccentric error and an image pickup apparatus will be provided. The imaging optical unit for guiding light to an image pickup device is structured so that a first holding member, for holding a reflection member for turning a light flux entering from the side of a subject along a first optical axis to a second optical axial direction almost at right angle, rotates freely about a rotating shaft between the retracting position where the first holding member is housed in a lens frame of the imaging optical unit and the using position where it is projected.

Abstract: An object of the present invention is to provide a compact size variable power optical system capable of producing a high quality image. The variable power optical system comprises a plurality of lens groups for forming an optical image on an image surface of an image pickup device. Among the plurality of lens groups, the first lens group, which is disposed in the most subject side has a negative refraction power, includes at least a lens having a negative refraction power and a reflective optical element for bending the optical axis. When varying the variable power, the axial distance between the first lens group and the image surface varies. When Nd denotes the refraction power of the lens having negative refraction power at d-line, the refraction power satisfies the conditional formula Nd>1.81.

Abstract: A variable magnification optical system of the present invention for forming an optical image of an object on a light-receiving surface of an image sensor with variable magnification includes: from the object side, at least a first lens unit having a positive optical power, a second lens unit having a negative optical power, a third lens unit having a positive optical power, and a fourth lens unit having a positive optical power. The variable magnification is performed by movement of at least the first lens unit and the third lens unit. A bending optical element for bending an optical axis is provided between the second lens unit and the third lens unit. Moreover, prescribed conditional formulae are fulfilled.

Abstract: A taking lens apparatus includes a zoom lens system that is composed of a plurality of lens units and that achieves zooming by varying the distances between the lens units and an image sensor that converts the optical image formed by the zoom lens system into an electrical signal. The zoom lens system has, from the object side,: a first lens unit having a negative optical power, a second lens unit disposed on the image side of the first lens unit and having a negative optical power, a third lens unit disposed on the image side of the second lens unit and having a positive optical power, a fourth lens unit disposed on the image side of the third lens unit and having a positive optical power, and a fifth lens unit disposed on the image side of the fourth lens unit and having a positive optical power. During zooming, the first lens unit remains stationary relative to the image sensor, and the second and third lens units move.

Abstract: A zoom lens system has, from the object side, a first lens unit, a second lens unit and a third lens unit. The first lens unit has a negative optical power as a whole. The second and third lens units have a positive optical power as a whole. In the zoom lens system, zooming is achieved by varying the distance between the first and second lens units, and at least one of the lens elements is a plastic lens element.

Abstract: A lens system has the first and second lens components from the object side. The first lens component has a negative optical power. The second lens component has a positive optical power. The lens system fulfills the conditions: 0.0<PRL/Y′<0.5, 0.5<Pf/f<1.0. In the conditions, PRL represents a distance in a direction perpendicular to the optical axis between the optical axis and an incident position where a lower ray of a most off-axial rays enters said second lens component, Y′ represents a largest image height, f represents a focal length of the entire lens system, and Pf represents a focal length of said second lens component.

Abstract: A zoom lens system has, from the object side, a first lens unit, a second lens unit and a third lens unit. The first lens unit has a negative optical power as a whole. The second and third lens units have a positive optical power as a whole. In the zoom lens system, zooming is achieved by varying the distance between the first and second lens units, and at least one of the lens elements is a plastic lens element.

Abstract: A taking lens device has a zoom lens system having an optical system that is comprised of a plurality of lens units and that achieves zooming by varying the unit-to-unit distances and an image sensor that converts an optical image formed by the zoom lens system into an electric signal. The zoom lens system is comprised of, from the object side, a first lens unit having a positive optical power, a second lens unit having a negative optical power, a third lens unit having a positive optical power, and a fourth lens unit having a negative optical power. At least one of the following conditional formula is fulfilled: 1.1<f1/fT<2.5, where f1 represents the focal length of the first lens unit, and fT represents the focal length of the entirety optical system at the telephoto end, and 0.3<D34W/D34T<2.5 where D34W and D34T represent axial distance between the third lens unit and the fourth lens unit at wide-angle end and telephoto end, respectively.