Abstract: Provided is a zoom lens including, in order from an object side to an image side, first to fourth lens units having positive, negative, positive, and positive refractive powers, respectively. In the zoom lens, during zooming, the first lens unit and the third lens unit do not move, and the second lens unit and the fourth lens unit move with loci different from each other, the first lens unit consists of, in order from the object side to the image side, a negative lens G11, a positive lens G12, and a positive lens G13, and an Abbe number ?1n of a material of the negative lens G11, an average value N1ave of refractive indices of materials of three lenses included in the first lens unit, a focal length f1 of the first lens unit, and a focal length f2 of the second lens unit are appropriately set.

Abstract: 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 rear lens group including one or more lens units, and an aperture stop. During zooming, with the first lens unit not moving, the second lens unit and at least one of the lens units of the rear lens group move. In this zoom lens, the configuration of the third lens unit and the location of the aperture stop are appropriately set.

Abstract: A lens assembly includes a first lens, a second lens, a third lens, a fourth lens and a fifth lens. The first lens is with positive refractive power. The second lens is with negative refractive power. The third lens is with positive refractive power. The fourth lens is a meniscus lens and includes a concave surface facing the object side and a convex surface facing the image side. The fifth lens includes a concave surface facing the image side. The first lens and the third lens are made of the same material and an Abbe number of the first lens is the same as an Abbe number of the third lens. An Abbe number of the first lens, an Abbe number of the third lens and an Abbe number of the fifth lens are greater than an Abbe number of the second lens.

Abstract: A variable magnification optical system includes, in order from the object side: a positive first lens group, which is fixed when changing magnification; a negative second lens group that moves from the object side to the image side when changing magnification from the wide angle end to the telephoto end; and a rearward lens group having a positive refractive power throughout the entire variable magnification range that includes at least one lens group that moves when changing magnification. The first lens group includes, in order from the object side, a positive first lens group front group, a positive first lens group middle group, and a first lens group rear group constituted by a negative lens. The first lens group front group and first lens group middle group include cemented lenses formed by cementing a negative lens and a positive lens, provided in this order from the object side, together.

Abstract: A zoom lens includes, in order from an object side to an image side, a first lens unit having positive refractive power, a second lens unit having negative refractive power, a third lens unit having positive refractive power, and a fourth lens unit having positive refractive power. During zooming from a wide-angle end to a telephoto end, the first lens unit does not move and at least the second lens unit and the fourth lens unit move. A distance between adjacent lens units varies during zooming. In the zoom lens, a lens configuration of the first lens unit, a lens configuration of the second lens unit, a focal length of each lens unit, a focal length of the zoom lens at a wide-angle end, and a lateral magnification of the second lens unit during focusing on an infinite-distance object at the telephoto end are appropriately set based on predetermined conditions.

Abstract: A zoom lens has, in order from an object: a first lens group having positive refractive power; a second lens group having negative refractive power; a third lens group having positive refractive power; and a fourth lens group having positive refractive power. Zooming is performed by changing an air gap between the lens groups. The fourth lens group includes, in order from the object, a first positive lens component, a second positive lens component having a convex surface facing the object, and a negative lens component. A specified conditional expression is satisfied.

Abstract: A zoom lens system includes a positive first lens group, a negative second lens group, a positive third lens group, and a positive fourth lens group. The second and third lens groups are moved during zooming. The first lens group includes a positive first sub-lens group which does not move during a focusing operation, and a positive second sub-lens group which moves during the focusing operation. The first sub-lens group includes at least one negative lens element, the second sub-lens group is a positive single lens element, and the following conditions (1) and (2) are satisfied: 60<?d1b<75 ??(1), and ?d1a<24??(2), wherein ?d1b and ?d1a_designates Abbe numbers at the d-line of the positive single lens element of the second sub-lens group and at the d-line of the negative lens element within the first sub-lens group, respectively.

Abstract: There is provided a zoom lens, consisting of sequentially from an object side: a first lens group having a positive refractive power and a focusing function; a second lens group having a negative refractive power and having a variator function of performing zooming; a third lens group having a positive refractive power and a diaphragm; a fourth lens group having a positive refractive power, and having a compensator function of correcting a position of an imaging plane at the time of zooming; and a fifth lens group having a positive or negative refractive power, wherein the second lens group is moved to the imaging plane side from the object side along an optical axis, and the fourth lens group is moved along the optical axis in a state of fixing the first lens group, the third lens group, and the fifth lens group at the time of zooming from a wide angle end to a telephoto end, and only the first lens group is moved along the optical axis at the time of focusing.

Abstract: A camera module and an apparatus for calibrating position of the camera module are provided, the camera module according to an exemplary embodiment of the present disclosure comprises a first sensor unit configured to obtain a first image; a second sensor unit configured to obtain a second image; and a third sensor unit configured to obtain a third image, wherein the second sensor unit is spaced apart from the first sensor unit at a predetermined distance, and the third sensor unit is spaced apart from the second sensor unit at a predetermined distance.

Abstract: A zoom lens includes a first lens unit having positive refractive power, a second lens unit having negative refractive power, a third lens unit having positive refractive power, and a fourth lens unit having positive refractive power, in order from an object side to an image side. During zooming, the first lens unit is not moved, and the second lens unit, the third lens unit, and the fourth lens unit are moved to change an interval between adjacent lens units. A moving amount m2 of the second lens unit during zooming from a wide angle end to a telephoto end, a focal length f2 of the second lens unit, and a focal length fw of a whole system at the wide angle end are each set appropriately.

Abstract: A camera lens includes from an object side to an image side: a first lens with positive refractive power; a second lens with negative refractive power; a third lens with negative refractive power; a fourth lens with positive refractive power and a fifth lens with negative refractive power. Specific conditions are satisfied. The camera lens has excellent optical properties.

Abstract: A zoom lens including, in order from object side, a positive first lens unit not moving for zooming, a negative second lens unit moving during zooming, at least one other lens unit moving during zooming as at least a third lens unit, and a rearmost lens unit closest to an image side not moving for zooming, and also including an aperture stop at the image side of the second lens unit, average values of Abbe numbers and relative partial dispersions of each of positive lenses and negative lenses forming the second lens unit, anomalous dispersion of a lens having a smallest Abbe number of negative lenses forming the rearmost lens unit, an axial distance between surface vertex positions of lenses closest to the object and image sides of the zoom lens, and a distance between the aperture stop and the negative lens at a wide angle end are appropriately set.

Abstract: A zoom lens including, in order from an object side: a positive first lens unit not moving for zooming; a negative second lens unit moving during zooming; a negative third lens unit moving during zooming; and a fourth lens unit not moving for zooming and including an aperture stop, the fourth lens unit including first and second sub-lens units arranged on object side and image plane side of the aperture stop, respectively, in which a relationship between a maximum height of an axial ray from an optical axis in the first sub-lens unit when focusing at infinity at a wide angle end, and a maximum height of an axial ray at the aperture stop when focusing at infinity at the wide angle end and of full open aperture, and a lateral magnification of the fourth lens unit when focusing at infinity at the wide angle end are appropriately set.

Abstract: A zoom lens includes, in order from an object side: first to fifth lens units respectively having positive, negative, positive, positive, and positive or negative refractive powers. The first lens unit is configured not to move for zooming, and the second, third, and fourth lens units are configured to move during zooming to change an interval between adjacent lens units. An aperture stop is arranged between the second and third lens units. The second lens unit is positioned on the image side and the third lens unit is positioned on the object side at a telephoto end. Focal lengths of the zoom lens at a wide angle end and of the third and fourth lens units, lateral magnifications of a lens group consisting of the third and fourth lens units at the wide angle end and at the telephoto end are each appropriately set.

Abstract: Provided is a zoom lens, including, 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; and a rear lens group including at least one lens unit, in which an interval between each pair of adjacent lens units is changed during zooming, and materials of lenses included in a lens unit arranged closest to the image side are appropriately set.

Abstract: The present invention has, in order along the optical axis from the object side: a first lens group (G1) that has positive refractive power; a second lens group (G2) that has negative refractive power; a third lens group (G3) that has positive refractive power; a fourth lens group (G4) that has positive refractive power; and a fifth lens group (G5). The fourth lens group (G4) is constituted by a single positive lens (L41), and the fifth lens group (G5) is constituted by a single lens (L51), which is fixed with respect to an image plane while power is being varied. The following conditional expression (1) is satisfied. 0.9<?2t·?3w/(?2w·?3t)<1.7 . . . (1), where ?2w denotes a magnification of the second lens group (G2) in the wide-angle end state, ?3w denotes a magnification of the third lens group (G3) in the wide-angle end state, ?2t denotes a magnification of the second lens group (G2) in the telephoto end state, and ?3t denotes a magnification of the third lens group (G3) in the telephoto end state.

Abstract: A positive-negative-positive-positive four group zoom lens system capable of achieving about 30 times variable magnification, the positive-negative-positive-positive four group zoom lens system including, sequentially from an object side to an image side: a first lens group having positive refractive power; a second lens group having negative refractive power; a third lens group having positive refractive power; and a fourth lens group having positive refractive power, wherein the first lens group includes one negative lens, the second lens group includes one positive lens, the third lens group includes a positive lens, the fourth lens group includes at least one positive lens, and a first condition, 0.03<|f2/ft|<0.08, is satisfied, wherein f2 denotes a focal length of the second lens group and ft denotes a focal length of the zoom lens system in a telephoto position.

Abstract: An object of the present invention is to provide a low-cost, miniature, wide-angle high-zoom-ratio zoom lens that has high imaging performance, and an imaging apparatus equipped with the zoom lens. To achieve the object, a zoom lens including a first lens group having positive refracting power, a second lens group having negative refracting power and a third lens group having positive refracting power in order from an object side in which a lens group P having positive refracting power is arranged closer to an image plane side than the third lens group.

Abstract: A zoom lens consists of a positive first lens group fixed during zooming, a negative second lens group moved during zooming, a positive third lens group moved during zooming to correct an image plane variation due to the zooming, and a positive fourth lens group fixed during zooming and includes a stop on the most object side. The second lens group includes two or more positive lenses and one or more negative lenses. The zoom lens satisfies predetermined conditional expressions with respect to the second lens group.

Abstract: A dual-aperture zoom camera comprising a Wide camera with a respective Wide lens and a Tele camera with a respective Tele lens, the Wide and Tele cameras mounted directly on a single printed circuit board, wherein the Wide and Tele lenses have respective effective focal lengths EFLW and EFLT and respective total track lengths TTLW and TTLT and wherein TTLW/EFLW>1.1 and TTLT/EFLT<1.0. Optionally, the dual-aperture zoom camera may further comprise an optical OIS controller configured to provide a compensation lens movement according to a user-defined zoom factor (ZF) and a camera tilt (CT) through LMV=CT*EFLZF, where EFLZF is a zoom-factor dependent effective focal length.

Abstract: 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, and a fourth lens unit having a positive refractive power. Each lens unit moves so that a distance between adjacent lens units changes during zooming. The third lens unit includes a positive lens G3i closest to the image side which has a concave meniscus surface on an image side. A conditional expression 0.03<R3i2/ft<0.25 is satisfied where R3i2 is a radius of curvature of a lens surface on the image side of the positive lens G3i, and ft is a focal length of the overall system at a telephoto end.

Abstract: An infrared laser zoom beam expanding system, applied to the field of laser processing, and comprising a first lens, a second lens and a third lens. The first lens and the third lens are plane-convex plus lenses, and the second lens is a meniscus minus lens. The first lens, the second lens and the third lens respectively comprise a first surface and a second surface, a third surface and a fourth surface as well as a fifth surface and a sixth surface. The radiuses of curvature of the first to sixth surfaces are ?, ?27, 10, 1.7, ?, ?103. The center thickness of the first to third lenses is 2, 1, 4. The outer diameters of the first to third lenses are 10, 3, 34. Proportions of the refractive indexes to the Abbe numbers of the first to third lenses are 1.8:25, 1.48:68, and 1.8:25. A distance between the second surface and the third surface is 10-27. An distance between the fourth surface and the fifth surface is 119-125, The unit is millimeter, and a tolerance is 5%.

Abstract: A photographic lens and a photographic apparatus including the same are provided. The photographic lens includes a first lens including a convex surface toward an object side and having a positive refractive power, a second lens including a concave surface toward an image side and having a negative refractive power, a third lens having a positive refractive power or a negative refractive power, a fourth lens having a positive refractive power or a negative refractive power, a fifth lens including a convex surface toward the image side and having a positive refractive power, and a sixth lens including a concave aspherical shape with respect to an optical axis toward the image side and having a negative refractive power. The first to sixth lenses may be sequentially arranged from the object side to the image side.

Abstract: A zoom lens has, in order from an object, a first lens group (G1) having positive refractive power; a second lens group (G2) having negative refractive power; a third lens group (G3) having positive refractive power; and a fourth lens group (G4) having positive refractive power. Zooming is performed by changing an air gap between the lens groups. The fourth lens group (G4) includes, in order from the object, a lens component (La) having positive or negative refractive power, a positive lens component (Lb), and a positive lens component (Lc) having a convex surface facing the object. Specified conditional expressions are satisfied.

Abstract: A zoom lens includes, in order from an object side to an image side, a first lens unit having positive refractive power, a second lens unit having negative refractive power, a third lens unit having positive refractive power, a fourth lens unit having negative refractive power, and a fifth lens unit having positive refractive power. At least the first, second, and third lens units move during zooming so that the first lens unit is located closer to an object side than an image side, the second lens unit is located closer to the image side, and the third lens unit is located closer to the object side at a telephoto end than a wide-angle end. Movement, focal length, and positioning parameters of first to third lens units, during zooming from the wide-angle end toward the telephoto end, are appropriately set based on mathematical conditions.

Abstract: A zoom lens having, in order from an object: a first lens group G1 having positive refractive power; a second lens G2 group having negative refractive power; a third lens group G3 having positive refractive power; and a fourth lens group G4 having positive refractive power, wherein the first lens group moves toward an image once then moves toward the object upon zooming from a wide-angle end state to a telephoto end state, and the following conditional expressions are satisfied: 0.050<fw/TLw<0.100 0.10<ft/TLt<0.80 0.10<fw/LG2<0.64 where fw denotes a focal length of the zoom lens in the wide-angle end state, ft denotes a focal length of the zoom lens in the telephoto end state, TLw denotes a total length of the zoom lens in the wide-angle end state, TLt denotes a total length of the zoom lens in the telephoto end state, and LG2 denotes a lens configuration length of the second lens group G2.

Abstract: The zoom lens consists essentially of a positive first lens group, a negative second lens group, an aperture stop, a third lens group, a positive fourth lens group and a fifth lens group in this order from the object side. The first, third, and fifth lens groups are fixed while the second and the fourth lens groups move when changing magnification from the wide angle end to the telephoto end, and the fourth lens group moves when focusing is performed. The fifth lens group consists essentially only of a single cemented lens having a meniscus shape with a convex surface toward the image side, and conditional formulas (1), (2) are satisfied when the maximum image height is Y, the air equivalent back focus is Bf and the distance along the optical axis from the aperture stop to the peak of the most-image-side lens surface is Lsr: 0.05<Y/Bf<0.20??(1) 1.8<Lsr/Bf<3.5??(2).

Abstract: A zoom lens includes, sequentially from an object side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, and a third lens group having a positive refractive power. When zoom is changed from a wide angle end to a telephoto end, an interval between the first lens group and the second lens group increases, and an interval between the second lens group and third lens group decreases. The second lens group comprises, sequentially from the object side, a second A lens group having a negative refractive power and a second B lens group having a negative refractive power, and the second B group is displaced in a direction perpendicular to an optical axis to perform a vibration prevention function.

Abstract: A zoom lens includes, in order from an object side to an image side, first to third lens units having negative, positive, and negative refractive power, respectively, and a rear lens group including a plurality of lens units and having overall positive refractive power, a distance between every adjacent lens unit included in the zoom lens is variable during zooming. The second lens unit moves in a direction nonparallel to an optical axis during image shake correction, the third lens unit moves in an optical axis direction during focusing, each of the second and third lens units consists of a single lens element, and a focal length of the entire zoom lens at a wide-angle end, a focal length of the second lens unit, and a focal length of the third lens unit are appropriately set.

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 a first lens unit having a positive refractive power and arranged closest to an object side. 0.50<Ym5/Yw30<1.00 is satisfied at a predetermined zoom position except for a wide-angle end and a telephoto end where Yw30 denotes an image height that provides a relative illumination of 0.3 at the wide-angle end, and Ym5 denotes an image height that provides the relative illumination of 0.05 at a predetermined zoom position except for a wide-angle end and a telephoto end.

Abstract: In a variable magnification optical system, consisting of a first lens group having a positive refractive power, a second lens group having a negative refractive power, a third lens group having a positive refractive power, and a fourth lens group having a positive refractive power, arranged in order from the object side, in which magnification is changed by moving the second lens group and focusing is performed by moving the fourth lens group, the first lens group consists of a positive lens and a positive cemented lens, arranged in order from the object side, the third lens group includes an aperture stop on the most object side, the fourth lens group consists of a positive lens, a negative lens, and a positive lens, arranged in order from the object side, with at least one surface being an aspherical surface, and the system satisfies given conditional expressions.

Abstract: The imaging lens substantially consists of a first lens group, a stop, a positive second lens group which is a focusing group, and a third lens group in this order from the object side. The first lens group substantially consists of a positive first sub lens group composed of a negative meniscus lens, a positive meniscus lens, and a positive lens; and a second sub lens group including a negative lens and a cemented lens, in this order from the object side. The second lens group substantially consists of a positive single lens or a cemented lens. The third lens group substantially consists of a cemented lens, a positive lens, and a negative lens in this order from the object side.

Abstract: A zoom lens includes, in order from object side: a positive first unit immovable for zooming; a negative second unit moving during zooming; a third unit moving during zooming; a stop; and a positive fourth unit immovable for zooming. The first unit includes, in order from object side, a fixed negative front first unit, a positive middle first unit moving for focusing, and a fixed positive rear first lens unit. Each of the front first and the second units includes at least one positive lens and two negative lenses. Average of Abbe constants and average of partial dispersion ratios of positive lenses in the front first unit, average of Abbe constants and average of partial dispersion ratios of negative lenses in the front first unit, combined focal length of the positive lenses in the front first unit and focal length of the front first unit are appropriately set.

Abstract: A zoom lens includes, in order from an object side to an image side thereof, 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 a fourth lens unit having a positive refractive power. A distance between adjacent ones of the lens units changes during zooming. The first lens unit consists of, in order from the object side to the image side thereof, one negative lens element and one positive lens element. Lengths of travel M1 and M2 of the first lens unit and the second lens unit, respectively, during zooming from a wide-angle end to a telephoto end, focal lengths f1 and f2 of the first lens unit and the second lens unit, respectively, and a zoom ratio Z of the zoom lens are set appropriately.

Abstract: The present invention provides a complex modular afocal variator in which a modular afocal variator is supplemented with additional optics to form a more complex, but still modular afocal variator system, that can impart internal focusing as well as active spherical and chromatic aberration corrective improvement.

Abstract: 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, and a fourth lens unit having a positive refractive power, and is configured to move the second lens unit, the third lens unit, and the fourth lens unit during a zooming operation to change an interval between adjacent lens units. A moving amount of the second lens unit during a zooming operation from a wide angle end to a telephoto end, a focal length of the second lens unit, and transverse magnification of the third lens unit at the wide angle end and the telephoto end are individually set appropriately.

Abstract: A zoom lens including, in order from an object: a first lens group having positive refractive power; a second lens group having negative refractive power; a third lens group having positive refractive power; and a fourth lens group having positive refractive power, wherein when f2 denotes a focal length of the second lens group, and fw denotes a focal length of the zoom lens in the wide-angle end state, the following conditional expression being satisfied: 1.90<(?f2)/fw<3.00.

Abstract: A zoom lens includes a first lens unit of a positive refractive power, a second lens unit of a negative refractive power, a third lens unit of a positive refractive power, and a rear lens group including one or more lens units in order from an object side to an image side, the first, second, and third lens units being moved towards an object side during zooming from a wide-angle end to a telephoto end with respect to an image plane, wherein the first lens unit includes a positive lens and a negative lens, and movement amounts of the first, second, and third lens units during zooming from a wide-angle end to a telephoto end and a focal length of the entire zoom lens at the wide-angle end are appropriately set.

Abstract: A zoom lens includes, in order from an object side to an image side thereof, 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 a rear lens group including one or more lens units. A distance between adjacent ones of the lens units changes during zooming. The second lens unit and the third lens unit each include a resin lens element. A focal length f2p of the resin lens element included in the second lens unit, a focal length f3p of the resin lens element included in the third lens unit, and a focal length ft of the zoom lens at a telephoto end are set to satisfy predetermined mathematical conditions.

Abstract: A zoom lens includes a first lens group, a second lens group, a third lens group and a fourth lens group, all of which are arranged in sequence from an object side to an image side along an optical axis. The first lens group is with positive refractive power and includes a first lens that is with negative refractive power and a second lens that is with positive refractive power. The second lens group is with negative refractive power. The third lens group is with positive refractive power and includes a third lens front group that is with positive refractive power and a third lens rear group that is with positive refractive power. The fourth lens group is with positive refractive power.

Abstract: A family of microscopes with illumination systems directing a sheet of light having an approximately planar extension in an illumination axis of an illumination beam path and in a transverse axis orthogonally oriented to the illumination axis. The microscopes have detection devices used to detect light that is emitted by a sample region. The detection devices including a detection lens system disposed in the detection beam path and an optical detection element spaced from a front lens of the detection lens system and independently adjustable thereof. The optical detection element continuously varies the size of a detection image field and/or continuously displaces a focal plane of detection in the P-region.

Abstract: A zoom lens includes in order from an object side: a positive first lens unit; a negative second lens unit which moves during zooming; a third lens unit; a stop; and a positive fourth lens unit. The first lens unit includes, in order from the object side, a negative first lens subunit which does not move, a positive second lens subunit which moves during focusing, and a positive third lens subunit which does not move. The first lens subunit is composed of one or more negative lenses, and the second lens subunit includes a positive lens and a negative lens. An average value of Abbe constants of the first lens subunit, an average value of Abbe constants of the positive lenses of the second lens subunit, and an average value of Abbe constants of the negative lenses of the second lens subunit are appropriately set.

Abstract: A tube lens used in combination with an objective of the infinity correction type that enlarges the image of an object includes a first lens group including a cemented lens and having a positive power, a second lens group having a negative power, and a third lens group including a positive lens and a negative lens and having a positive power as a whole, in this order from the object side.

Abstract: Composing a projection zoom lens with a first lens group disposed on the most magnification side and having a positive power, the lens group being fixed at the time of zooming, a final lens group disposed on the most reduction side and having a negative power, the lens group being fixed at the time of zooming, and a plurality of lens groups disposed between the first and final lens groups and moved at the time of zooming along an optical axis in association with each other for the zooming and correction of image plane shift arising from the zooming, in which the final lens group includes a lens having a positive power on the most reduction side.

Abstract: A zoom lens includes, in order from an object side to an image side, a first lens unit having positive refractive power, a second lens unit having negative refractive power, a third lens unit having positive refractive power, and a rear lens group including one or more lens units. An interval between adjacent lens units is changed in zooming, the first lens unit is moved closer to the object side at a telephoto end than at a wide-angle end. The first lens unit includes at least four lenses. An Abbe number and a material of a positive lens included in the first lens unit satisfy predetermined values. And, a focal length f1 of the first lens unit, and an amount of movement M1 of the first lens unit at zooming from the wide-angle end to the telephoto end are appropriately set.

Abstract: A zoom lens includes, in order from an object side to an image side, a first lens unit having positive refractive power, a second lens unit having negative refractive power, a reflecting unit for bending an optical path, and a rear lens group including two or more lens units, wherein, during zooming, the first and second lens units are moved and the reflecting unit is not moved, and wherein an amount of movement of the first lens unit during zooming from a wide-angle end to a telephoto end, a distance on an optical axis from a reflecting surface of the reflecting unit to an image plane, a distance on the optical axis from a lens surface of the second lens unit closest to the image side to the reflection surface of the reflecting unit at the wide-angle end, and a focal length of the second lens unit are appropriately set.

Abstract: A zoom lens includes a first lens-group having positive refractive power, a second lens-group having negative refractive power, a third lens-group having positive refractive power, and a fourth lens-group having positive refractive power, in this order from an object side, and a stop located between a most image-side surface of the second lens-group and a most image-side surface of the third lens-group. Distances between the lens-groups change when magnification is changed from a wide-angle end to a telephoto end. The second lens-group consists of a negative lens, a biconcave lens and a positive lens in this order from the object side. The third lens-group consists of a positive lens, a cemented lens of a positive lens and a negative lens, a negative meniscus lens with its concave surface facing the object side, and a biconvex lens in this order from the object side. A predetermined conditional formula is satisfied.

Abstract: A high-power zoom lens that achieves size and price reduction, and at the same time provides high-quality imaging. This lens includes at least four lens groups arranged along an optical axis, which are moveable along the axis in order to achieve changes in magnification. The first, third, and fourth lens groups have positive refractive powers, and the second group has a negative refractive power. The second lens group includes a negative meniscus lens arranged closest to the object, provided with a convex surface at the object side. A negative lens is arranged next to the negative meniscus lens, and a negative lens provided with a concave surface at the object side is arranged closest to the image. The fourth lens group includes at least two positive lenses and one negative lens.

Abstract: A zoom lens includes, in order from an object side to an image side: a first lens group that has a positive refractive power; a second lens group that has a negative refractive power; a third lens group that has a positive refractive power; and a fourth lens group that has a positive refractive power. During zooming from a wide-angle end to a telephoto end, the first lens group is stationary relative to an imaging surface, and the second lens group is moved to the image side in an optical axis direction so as to decrease a space between the second lens group and the third lens group. The third lens group includes a positive lens, a negative lens, and a cemented lens. The zoom lens satisfies ?0.95<fg3_neg/fg3<?0.5. Here, fg3_neg is a focal length of the negative lens of the third lens group, and fg3 is a focal length of the third lens group.