Abstract: To reduce degradation of image quality occurring upon correction of an image shake, provided is an image pickup apparatus including: an image pickup optical system; an image pickup element for photoelectrically converting an image formed by the image pickup optical system; a processing unit for processing a taken image; a detection unit for detecting a shake of the image pickup apparatus; and an image stabilizing unit for decentering an image stabilizing lens unit formed as a part of the image pickup optical system based on a detection result from the detection unit. The processing unit performs the process by using an image restore filter corresponding to a position of the image stabilizing lens unit at a time of image taking.

Abstract: The optical system of the present invention includes a plurality of lens groups and a variable focus lens. Here, the variable focus lens satisfies the following condition: ?0.023?{(nA?1)/?A?(nB?1)/?B}/(nB?nA)?0.023 where nA and nB respectively denote the d-line refractive indices of a first medium and a second medium, and ?A and ?B respectively denote the d-line Abbe numbers of the first and second media. In addition, the plurality of lens groups moves in an optical axial direction; and the following condition holds: 0.8<|fao|/fw<5 where fao denotes the composite focal distance at the wide angle end of the part of the optical system, and fw denotes the focal distance of the entire system at the wide angle end.

Abstract: The optical system of the present invention includes a plurality of lens groups and a variable focus lens. Here, the variable focus lens satisfies the following condition: ?0.023?{(nA?1)/?A?(nB?1)/?B}/(nB?nA)?0.023 where nA and nB respectively denote the d-line refractive indices of a first medium and a second medium, and ?A and ?B respectively denote the d-line Abbe numbers of the first and second media. In addition, the plurality of lens groups moves in an optical axial direction; and the following condition holds: 0.8<|fao|/fw<5 where fao denotes the composite focal distance at the wide angle end of the part of the optical system, and fw denotes the focal distance of the entire system at the wide angle end.

Abstract: To reduce degradation of image quality occurring upon correction of an image shake, provided is an image pickup apparatus including: an image pickup optical system; an image pickup element for photoelectrically converting an image formed by the image pickup optical system; a processing unit for processing a taken image; a detection unit for detecting a shake of the image pickup apparatus; and an image stabilizing unit for decentering an image stabilizing lens unit formed as a part of the image pickup optical system based on a detection result from the detection unit. The processing unit performs the process by using an image restore filter corresponding to a position of the image stabilizing lens unit at a time of image taking.

Abstract: A zoom lens system includes, in order from an object side to an image side, first, second, third, and fourth lens units having positive, negative, positive, and positive optical powers, respectively. The first lens unit includes one negative lens element and two positive lens elements, and moves during zooming. The zoom lens system satisfies the following condition: 0.05<f1/(st1×ft/fw)<0.2 1.5<?3T/?3W<3.6 where f1 denotes a focal length of the first lens unit, st1 denotes a distance between positions of the first lens unit at a wide-angle end and at a telephoto end, fw and ft denote focal lengths of the entire system at the wide-angle end and at the telephoto end, respectively, and ?3W and ?3T denote lateral magnifications of the third lens unit at the wide-angle end and at the telephoto end, respectively.

Abstract: A zoom lens device includes, 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. The zoom lens device is formed so that a distance Ximg between a position of the first lens unit at the wide-angle end and a position of the first lens unit that is maximally moved towards the image side, a distance Xobj between the position of the first lens unit at the wide-angle end and a position of the first lens unit that is maximally moved towards the object side, and a focal length fw of the zoom lens device at the wide-angle end are suitable values.

Abstract: A zoom lens system includes a first lens unit having a negative refractive power, at least one lens unit having a positive refractive power, and an optical element composed of a material having an Abbe number and a partial dispersion that satisfy a predetermined condition. The first lens unit, an aperture stop, and the at least one lens unit are arranged in this order from the object side to the image side. The zoom lens system performs zooming while changing the distance between the lens units. The focal length fN of the optical element, the distance Lt from the aperture stop to the optical element in the telephoto end state, the overall length of the zoom lens system Tt in the telephoto end state, and the focal lengths fw and ft in the wide-angle end and telephoto end states are set at appropriate values.

Abstract: A compact zoom lens includes a first lens unit disposed closest to an object side, an aperture, and a rear lens group. The first lens unit includes a first diffraction optical part having positive refractive power, and the rear lens group includes a second diffraction optical part having positive refractive power. The power relation between the two diffraction optical parts and the positions of the diffraction optical parts are set appropriately. The zoom lens can have a high zoom ratio wherein chromatic aberration is fully corrected, and an image pickup apparatus employing this zoom lens can be provided.

Abstract: A zoom lens system includes, in order from an object side to an image side, first, second, third, and fourth lens units having positive, negative, positive, and positive optical powers, respectively. The first lens unit includes one negative lens element and two positive lens elements, and moves during zooming. The zoom lens system satisfies the following condition: 0.05<f1/(st1×ft/fw)<0.2 1.5<?3T/?3W<3.6 where f1 denotes a focal length of the first lens unit, st1 denotes a distance between positions of the first lens unit at a wide-angle end and at a telephoto end, fw and ft denote focal lengths of the entire system at the wide-angle end and at the telephoto end, respectively, and ?3W and ?3T denote lateral magnifications of the third lens unit at the wide-angle end and at the telephoto end, respectively.

Abstract: A zoom lens device includes, 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. The zoom lens device is formed so that a distance Ximg between a position of the first lens unit at the wide-angle end and a position of the first lens unit that is maximally moved towards the image side, a distance Xobj between the position of the first lens unit at the wide-angle end and a position of the first lens unit that is maximally moved towards the object side, and a focal length fw of the zoom lens device at the wide-angle end are suitable values.

Abstract: A compact zoom lens includes a first lens unit disposed closest to an object side, an aperture, and a rear lens group. The first lens unit includes a first diffraction optical part having positive refractive power, and the rear lens group includes a second diffraction optical part having positive refractive power. The power relation between the two diffraction optical parts and the positions of the diffraction optical parts are set appropriately. The zoom lens can have a high zoom ratio wherein chromatic aberration is fully corrected, and an image pickup apparatus employing this zoom lens can be provided.

Abstract: A zoom lens system includes a first lens unit having a negative refractive power, at least one lens unit having a positive refractive power, and an optical element composed of a material having an Abbe number and a partial dispersion that satisfy a predetermined condition. The first lens unit, an aperture stop, and the at least one lens unit are arranged in this order from the object side to the image side. The zoom lens system performs zooming while changing the distance between the lens units. The focal length fN Of the optical element, the distance Lt from the aperture stop to the optical element in the telephoto end state, the overall length of the zoom lens system Tt in the telephoto end state, and the focal lengths fw and ft in the wide-angle end and telephoto end states are set at appropriate values.

Abstract: At least one exemplary embodiment is directed to a zoom lens system having a telephoto-type configuration at the telephoto end. When assuming that an Abbe number is vd, and a partial dispersion ratio is ?gF, this zoom lens system includes a refractive optical element having positive refracting power made up of a solid material that can satisfy the following conditions: ?2.100×10?3·vd+0.693<?gF 0.555<?gF<0.9 Thus, facilitating the configuration of a zoom lens system capable of appropriately correcting and/or reducing various aberrations, including a chromatic aberration straddling the entire zoom area.

Abstract: At least one exemplary embodiment is directed to a zoom lens system having a telephoto-type configuration at the telephoto end. When assuming that an Abbe number is vd, and a partial dispersion ratio is ?gF, this zoom lens system includes a refractive optical element having positive refracting power made up of a solid material that can satisfy the following conditions: ?2.100×10?3·vd+0.693<?gF 0.555<?gF<0.9 Thus, facilitating the configuration of a zoom lens system capable of appropriately correcting and/or reducing various aberrations, including a chromatic aberration straddling the entire zoom area.