Abstract: A zoom lens includes, in order from an object side, a first lens group of which at least a part moves for focusing, a plurality of lens groups which move in zooming, an aperture stop, and a final lens group which does not move for zooming. The final lens group includes a separation element PR for separating an incident light thereon into a transmitted light and a reflected light, a relay unit LR having a positive refractive power on which the transmitted light is incident, and a relay unit LA having a positive refractive power on which the reflected light is incident. An inequality about Fwp/Fw is satisfied, where Fw is a focal length at a wide angle end of the zoom lens via the relay unit LR and FwP is a focal length at the wide angle end of the zoom lens via the relay unit LA.

Abstract: Provided is a zoom lens including, from object side: one/two first positive units including a lens unit arranged at closest to object side not movable for zooming ; one/two second negative units movable toward image side for zooming from wide end to telephoto end; one/two third units including a negative unit arranged closest to object side and movable along a locus convex toward object side for zooming; a fourth positive unit movable for zooming; and a fifth unit, and including an aperture stop in image side of the fourth unit. A distance between object side surface of the first unit and the aperture stop, a length of the first unit, and movement amounts of the second unit from wide end to telephoto end and of the fourth unit from wide end to an intermediate zoom state where the second and third units are closest to each other are set appropriately.

Abstract: Provided is a zoom lens including, from object side: one/two first positive units including a lens unit arranged at closest to object side not movable for zooming ; one/two second negative units movable toward image side for zooming from wide end to telephoto end; one/two third units including a negative unit arranged closest to object side and movable along a locus convex toward object side for zooming; a fourth positive unit movable for zooming; and a fifth unit, and including an aperture stop in image side of the fourth unit. A distance between object side surface of the first unit and the aperture stop, a length of the first unit, and movement amounts of the second unit from wide end to telephoto end and of the fourth unit from wide end to an intermediate zoom state where the second and third units are closest to each other are set appropriately.

Abstract: In a zoom lens in which the interval between adjacent lens units changes during zooming, a magnification-varying lens group includes a lens group V having a negative refractive power and a lens unit C having a negative or positive refractive power. The lens group V includes a first magnification-varying lens group V1 including a lens unit V1a having a negative refractive power and a lens unit V1b having a negative refractive power. The lens units V1a and V1b move toward the image side such that the interval between the two lens units is largest at the telephoto end. The lens unit interval m1 on the optical axis between the lens units V1a and V1b at the wide angle end and the maximum lens unit interval m2 on the optical axis between the lens units V1a and V1b during zooming are set as appropriate.

Abstract: In a zoom lens in which the interval between adjacent lens units changes during zooming, a magnification-varying lens group includes a lens group V having a negative refractive power and a lens unit C having a negative or positive refractive power. The lens group V includes a first magnification-varying lens group V1 including a lens unit V1a having a negative refractive power and a lens unit V1b having a negative refractive power. The lens units V1a and V1b move toward the image side such that the interval between the two lens units is largest at the telephoto end. The lens unit interval m1 on the optical axis between the lens units V1a and V1b at the wide angle end and the maximum lens unit interval m2 on the optical axis between the lens units V1a and V1b during zooming are set as appropriate.

Abstract: The zoom lens according to the present invention includes, in order from an object side to an image side: a first lens unit having a positive refractive power that does not move for zooming; a second lens unit having a negative refractive power that moves during zooming; a third lens unit having a negative refractive power that moves along a locus convex toward the object side during zooming from a wide angle end to a telephoto end; a fourth lens unit having a positive refractive power that moves during zooming; an aperture stop; and a fifth lens unit having a positive refractive power that does not move for zooming, in which the fourth lens unit has a lens surface having an aspherical shape with which the positive refractive power is weakened.

Abstract: A zoom lens includes, in order from the object side, a positive first unit, a zooming lens group constituted by at least two lens units having a zooming function and a function of correcting image plane variation with zooming, and a last lens unit disposed on the most image side having an imaging effect and not moving for zooming. The first unit includes a negative first sub unit not moving for focusing, a second sub unit moving during focusing, and a positive third sub unit not moving for focusing. The first sub unit is composed of one or more concave lenses, and the third sub unit is composed of one or more convex lenses. Of the first and third sub units, the refractive powers, the average Abbe constants and the paraxial converted beam heights at the telephoto end are appropriately set.

Abstract: A zoom lens include, from an object side: a positive first unit that does not move for zooming; a negative second unit that moves during zooming; a negative third unit that moves during zooming; a positive fourth unit that moves during zooming; and a positive fifth unit, wherein the second unit moves towards the image side during zooming towards a telephoto end, the third unit moves towards the object side during focus adjustment towards a close distance, and a focal length of the zoom lens at the wide angle end, a zoom ratio, a focal length of the zoom lens at a zoom position where the third unit is closest to the object, a focal length of the first unit, a focal length of the second unit, a focal length of the third unit, and a focal length of the fourth unit are appropriately set.

Abstract: The zoom lens according to the present invention includes, in order from an object side to an image side: a first lens unit having a positive refractive power that does not move for zooming; a second lens unit having a negative refractive power that moves during zooming; a third lens unit having a negative refractive power that moves along a locus convex toward the object side during zooming from a wide angle end to a telephoto end; a fourth lens unit having a positive refractive power that moves during zooming; an aperture stop; and a fifth lens unit having a positive refractive power that does not move for zooming, in which the fourth lens unit has a lens surface having an aspherical shape with which the positive refractive power is weakened.

Abstract: Lens apparatus includes adjacent concave and convex lens surfaces adjacent with an air layer therebetween. At least one of the lens surfaces includes an antireflection film including multiple subwavelength structures at an average pitch of 400 nm or smaller. The surface satisfies: 0.7<R1/R2<1.3, and |?2??1|>15°, provided that: D=f/FNo, ?1=sin?1(D/(2×fi)), and ?2=sin?1((h×D)/R2), where f and FNo represent focal length and F-number of the entire optical system, f1 represents focal length of an optical system on object side with respect to the air layer between the lens surfaces, h represents axial conversion beam height on the at least one surface having anti-reflection film, R1 and R2 represent curvature radii of surfaces of respective object and image sides between the lens surfaces.

Abstract: A zoom lens includes, in order from the object side, a positive first unit, a zooming lens group constituted by at least two lens units having a zooming function and a function of correcting image plane variation with zooming, and a last lens unit disposed on the most image side having an imaging effect and not moving for zooming. The first unit includes a negative first sub unit not moving for focusing, a second sub unit moving during focusing, and a positive third sub unit not moving for focusing. The first sub unit is composed of one or more concave lenses, and the third sub unit is composed of one or more convex lenses. Of the first and third sub units, the refractive powers, the average Abbe constants and the paraxial converted beam heights at the telephoto end are appropriately set.

Abstract: An image pickup apparatus includes: a lens apparatus; and a camera apparatus that can be attached and removed from the lens apparatus, wherein the camera apparatus includes: an image pickup element; and an optical element configured to be inserted and removed from an optical path, the optical element is a ND filter, and the ND it has a surface with positive refractive power. A ratio of a thickness of the optical element on an optical axis and a thickness of the optical length adjustment unit on the optical axis is appropriately set.

Abstract: Provided is a camera apparatus including a lens apparatus which is attachable thereto and detachable therefrom, the camera apparatus including: an optical system; and an optical element which is insertable to and removable from an optical path of the optical system, in which: the optical element includes a surface having positive refractive power; and the optical system includes a surface having negative refractive power.

Abstract: Provided is an adapter optical system attachable between an image pickup lens and a camera body, the adapter optical system including, in order from an object side: a first optical unit having negative refractive power; a second optical unit that is insertable in and removable from an optical path; and a third optical unit having positive refractive power, in which the following expression is satisfied: 0.03<|?2|<0.50, where ?a2 represents an incident converted inclination angle obtained by normalizing an incident inclination angle of an axial beam entering the second optical unit inserted in an optical path with an exit inclination angle of an axial paraxial ray emerging from a surface closest to an image plane side in the adapter optical system being set to one (1).

Abstract: A zoom lens includes a first lens unit, a magnification-varying system including at least a second lens unit and a third lens unit, and a fourth lens unit. The fourth lens first unit has a first lens subunit having a negative refractive power, a second lens subunit having a negative refractive power, and a third lens subunit having a positive refractive power. The fourth lens unit satisfies the following conditional expression: 1.2<f41/f42<3.5, where f41 represents a focal length of the first lens subunit, and f42 represents a focal length of the second lens subunit.

Abstract: A color separating optical system includes a first prism including a second surface for separating an beam into reflected and transmitted beams; and a second prism including a third surface disposed to have an air gap interposed between the third and second surfaces and a fourth surface for separating a beam from the third surface into reflected and transmitted beams. At least one of the second and third surfaces has a multi-layer film, and 0.70<nd×cos ?2A/(?/4)<1.2 is satisfied, where ?2A=sin?1 {(Ng/Nm)sin(?2)}, ? central wavelength in a wavelength range of the beam to be separated by the second prism, nd thickness of an outermost layer of the multi-layer film, Nm refractive index of the outermost layer for the central wavelength, Ng refractive index of a glass material of the second prism for the central wavelength in the wavelength range of color light to be separated, and ?2 apex angle of the second prism.

Abstract: Lens apparatus includes adjacent concave and convex lens surfaces adjacent with an air layer therebetween. At least one of the lens surfaces includes an antireflection film including multiple subwavelength structures at an average pitch of 400 nm or smaller. The surface satisfies: 0.7<R1/R2<1.3, and |?2??1|>15°, provided that: D=f/FNo, ?1=sin?1(D/(2×fi)), and ?2=sin?1((h×D)/R2), where f and FNo represent focal length and F-number of the entire optical system, f1 represents focal length of an optical system on object side with respect to the air layer between the lens surfaces, h represents axial conversion beam height on the at least one surface having anti-reflection film, R1 and R2 represent curvature radii of surfaces of respective object and image sides between the lens surfaces.

Abstract: Provided is an adapter optical system attachable between an image pickup lens and a camera body, the adapter optical system including, in order from an object side: a first optical unit having negative refractive power; a second optical unit that is insertable in and removable from an optical path; and a third optical unit having positive refractive power, in which the following expression is satisfied: 0.03<|?a2|<0.50, where ?a2 represents an incident converted inclination angle obtained by normalizing an incident inclination angle of an axial beam entering the second optical unit inserted in an optical path with an exit inclination angle of an axial paraxial ray emerging from a surface closest to an image plane side in the adapter optical system being set to one (1).

Abstract: An image pickup apparatus includes: a lens apparatus; and a camera apparatus that can be attached and removed from the lens apparatus, wherein the camera apparatus includes: an image pickup element; and an optical element configured to be inserted and removed from an optical path, the optical element is a ND filter, and the ND it has a surface with positive refractive power. A ratio of a thickness of the optical element on an optical axis and a thickness of the optical length adjustment unit on the optical axis is appropriately set.

Abstract: Provided is a camera apparatus including a lens apparatus which is attachable thereto and detachable therefrom, the camera apparatus including: an optical system; and an optical element which is insertable to and removable from an optical path of the optical system, in which: the optical element includes a surface having positive refractive power; and the optical system includes a surface having negative refractive power.