Abstract: A zoom lens includes in order from an object 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 fifth lens unit having a positive refractive power. The first lens unit includes a positive lens, and the second lens unit includes a positive lens, and the following conditional expressions (1), (2), (3), and (4) are satisfied: ?0.015?Tp2G_min_p?0.015??(1), 70.3??d1G_max_p??(2), 1.76?nd2G_max_p?2.3??(3), and 0.3?|f2/f3|?0.9??(4).

Abstract: A variable magnification optical system includes a plurality of lens element, and includes in order from an object 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, and at least one lens unit. An aperture stop is either positioned between the second lens unit and the third lens unit, or positioned in the third lens unit. At the time of zooming from a wide angle end to a telephoto end, the first lens unit is fixed, the second lens unit moves from the object side to an image-plane side, and at least one of lens units positioned on an image side of the aperture stop moves. The first lens unit includes at least four positive lens elements and at least two negative lens elements.

Abstract: A variable magnification optical system includes 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, and at least one lens unit. A second predetermined positive lens element satisfies conditional expressions (1) and (2) and a second predetermined negative lens element satisfies the following conditional expressions (3) and (4). The second lens unit includes three sub-lens units and the following conditional expressions (5) and (6) are satisfied: 0.520<(?g,F)G2p<0.610??(1), 0.680<(?C,t)G2p<0.900??(2), 0.520<(?g,F)G2n<0.560??(3), 0.750<(?C,t)G2n<0.900??(4), ?0.25<fG21/fG22<0.90??(5), and ?0.70<fG21/fG23<0.40??(6).

Abstract: A zoom lens with a bent optical path includes, in order from the object side to the image side, a first lens unit including the reflecting member and having a negative refractive power, a second lens unit having a positive refractive power, a third lens unit having a negative refractive power, and a fourth lens unit having a positive refractive power. During zooming from the wide angle end to the telephoto end, the second lens unit moves closer to the first lens unit only toward the object side, the third lens unit moves in such a way that it becomes closest to the second lens unit at an intermediate focal length position in the course of zooming as compared to the state at the wide angle end and the state at the telephoto end, and the fourth lens unit moves. The zoom lens satisfies a certain condition.

Abstract: A zoom lens comprises in order from an object side, a first lens unit having a positive refractive power, a second lens unit having a negative refractive power, and a third lens unit having a positive refractive power, and the third unit having a positive refractive power comprises in order from the object side, a first lens component having a positive refractive power, and a second lens component having a negative refractive power in which, a lens having a positive refractive power and a lens having a negative refractive power are cemented, and the zoom lens satisfies the following conditional expressions (1), (2), and (3) 1.4<|f3_2p/f3_2n|<2.6??(1) nd3_2p?nd3_2n?0??(2) nd3_2n?1.8??(3).

Abstract: A variable magnification optical system includes 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, and at least one lens unit. A second predetermined positive lens element satisfies conditional expressions (1) and (2) and a second predetermined negative lens element satisfies the following conditional expressions (3) and (4). The second lens unit includes three sub-lens units and the following conditional expressions (5) and (6) are satisfied: 0.520<(?g,F)G2p<0.610??(1), 0.680<(?C,t)G2p<0.900??(2), 0.520<(?g,F)G2n<0.560??(3), 0.750<(?C,t)G2n<0.900??(4), ?0.25<fG21/fG22<0.90??(5), and ?0.70<fG21/fG23<0.40??(6).

Abstract: A variable magnification optical system includes a plurality of lens element, and includes in order from an object 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, and at least one lens unit. An aperture stop is either positioned between the second lens unit and the third lens unit, or positioned in the third lens unit. At the time of zooming from a wide angle end to a telephoto end, the first lens unit is fixed, the second lens unit moves from the object side to an image-plane side, and at least one of lens units positioned on an image side of the aperture stop moves. The first lens unit includes at least four positive lens elements and at least two negative lens elements.

Abstract: A zoom lens includes, in order from the object side, a first lens unit having a positive focal length, a second lens unit having a negative focal length, a third lens unit having a positive focal length, a fourth lens unit having a negative focal length, and a fifth lens unit having a positive focal length, wherein following Conditional Expressions (1) and (2) are satisfied: 0.3?D34W/D45W?1??(1), and 0.2?(D34W/D45W)/(D34T/D45T)?0.6??(2).

Abstract: A zoom lens comprises in order from an object side, a first lens unit having a positive refractive power, a second lens unit having a negative refractive power, and a third lens unit having a positive refractive power, and the third unit having a positive refractive power comprises in order from the object side, a first lens component having a positive refractive power, and a second lens component having a negative refractive power in which, a lens having a positive refractive power and a lens having a negative refractive power are cemented, and the zoom lens satisfies the following conditional expressions (1), (2), and (3) 1.4<|f3_2p/f3_2n|<2.6??(1) nd3_2p?nd3_2n?0??(2) nd3_2n?1.8??(3).

Abstract: A zoom lens comprises in order from an object side, a first lens unit having a positive refractive power, a second lens unit having a negative refractive power, and a third lens unit having a positive refractive power, and the third unit having a positive refractive power comprises in order from the object side, a first lens component having a positive refractive power, and a second lens component having a negative refractive power in which, a lens having a positive refractive power and a lens having a negative refractive power are cemented, and the zoom lens satisfies the following conditional expressions (1), (2), and (3). 1.4<|f3_2p/f3_2n|<2.6??(1) nd3_2p?nd3_2n?0??(2) nd3_2n?1.8??(3).

Abstract: A zoom lens includes in order from an object 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 fifth lens unit having a positive refractive power. The first lens unit includes a positive lens, and the second lens unit includes a positive lens, and the following conditional expressions (1), (2), (3), and (4) are satisfied: ?0.015?Tp2G_min_p?0.015??(1), 70.3??d1G_max_p??(2), 1.76?nd2G_max_p?2.3??(3), and 0.3?|f2/f3|?0.9??(4).

Abstract: A zoom lens includes, in order from the object side, a first lens unit having a positive focal length, a second lens unit having a negative focal length, a third lens unit having a positive focal length, a fourth lens unit having a negative focal length, and a fifth lens unit having a positive focal length, wherein following Conditional Expressions (1) and (2) are satisfied: 0.3?D34W/D45W?1??(1), and 0.2?(D34W/D45W)/(D34T/D45T)?0.6??(2).

Abstract: A zoom lens with a bent optical path includes, in order from the object side to the image side, a first lens unit including the reflecting member and having a negative refractive power, a second lens unit having a positive refractive power, a third lens unit having a negative refractive power, and a fourth lens unit having a positive refractive power. During zooming from the wide angle end to the telephoto end, the second lens unit moves closer to the first lens unit only toward the object side, the third lens unit moves in such a way that it becomes closest to the second lens unit at an intermediate focal length position in the course of zooming as compared to the state at the wide angle end and the state at the telephoto end, and the fourth lens unit moves. The zoom lens satisfies a certain condition.

Abstract: A zoom lens with a bent optical path includes, in order from the object side to the image side, a first lens unit including the reflecting member and having a negative refractive power, a second lens unit having a positive refractive power, a third lens unit having a negative refractive power, and a fourth lens unit having a positive refractive power. During zooming from the wide angle end to the telephoto end, the second lens unit moves closer to the first lens unit only toward the object side, the third lens unit moves in such a way that it becomes closest to the second lens unit at an intermediate focal length position in the course of zooming as compared to the state at the wide angle end and the state at the telephoto end, and the fourth lens unit moves. The zoom lens satisfies a certain condition.

Abstract: A zoom lens comprises in order from an object side, a first lens unit having a positive refractive power, a second lens unit having a negative refractive power, and a third lens unit having a positive refractive power, and the third unit having a positive refractive power comprises in order from the object side, a first lens component having a positive refractive power, and a second lens component having a negative refractive power in which, a lens having a positive refractive power and a lens having a negative refractive power are cemented, and the zoom lens satisfies the following conditional expressions (1), (2), and (3) 1.4<|f3_2p/f3_2n|<2.6??(1) nd3_2p?nd3_2n?0??(2) nd3_2n?1.

Abstract: A zoom lens comprises in order from an object side, a first lens unit having a positive refractive power, a second lens unit having a negative refractive power, and a third lens unit having a positive refractive power, and the third unit having a positive refractive power comprises in order from the object side, a first lens component having a positive refractive power, and a second lens component having a negative refractive power in which, a lens having a positive refractive power and a lens having a negative refractive power are cemented, and the zoom lens satisfies the following conditional expressions (1), (2), and (3) 1.4<|f3_2p/f3_2n|<2.6??(1) nd3_2p?nd3_2n?0??(2) nd3_2n?1.

Abstract: A zoom lens comprises in order from an object side, a first lens unit having a positive refractive power, a second lens unit having a negative refractive power, and a third lens unit having a positive refractive power, and the third unit having a positive refractive power comprises in order from the object side, a first lens component having a positive refractive power, and a second lens component having a negative refractive power in which, a lens having a positive refractive power and a lens having a negative refractive power are cemented, and the zoom lens satisfies the following conditional expressions (1), (2), and (3) 1.4<|f3_2p/f3_2n|<2.6??(1) nd3_2p?nd3_2n?0??(2) nd3_2n?1.

Abstract: A zoom lens comprises in order from an object side, a first lens unit having a positive refractive power, a second lens unit having a negative refractive power, and a third lens unit having a positive refractive power, and the third unit having a positive refractive power comprises in order from the object side, a first lens component having a positive refractive power, and a second lens component having a negative refractive power in which, a lens having a positive refractive power and a lens having a negative refractive power are cemented, and the zoom lens satisfies the following conditional expressions (1), (2), and (3) 1.4<|f3—2p/f3—2n|<2.6??(1) nd3—2p?nd3—2n?0??(2) nd3—2n?1.8??(3).

Abstract: A zoom lens with a bent optical path includes, in order from the object side to the image side, a first lens unit including the reflecting member and having a negative refractive power, a second lens unit having a positive refractive power, a third lens unit having a negative refractive power, and a fourth lens unit having a positive refractive power. During zooming from the wide angle end to the telephoto end, the second lens unit moves closer to the first lens unit only toward the object side, the third lens unit moves in such a way that it becomes closest to the second lens unit at an intermediate focal length position in the course of zooming as compared to the state at the wide angle end and the state at the telephoto end, and the fourth lens unit moves. The zoom lens satisfies a certain condition.

Abstract: A zoom lens with a bent optical path includes, in order from the object side to the image side, a first lens unit including the reflecting member and having a negative refractive power, a second lens unit having a positive refractive power, a third lens unit having a negative refractive power, and a fourth lens unit having a positive refractive power. During zooming from the wide angle end to the telephoto end, the second lens unit moves closer to the first lens unit only toward the object side, the third lens unit moves in such a way that it becomes closest to the second lens unit at an intermediate focal length position in the course of zooming as compared to the state at the wide angle end and the state at the telephoto end, and the fourth lens unit moves. The zoom lens satisfies a certain condition.