Abstract: A converter lens includes three or more negative lenses and increases the focal length of an entire system, in which an average refractive index Ndave at the d-line (wavelength of 587.56 nm) of a material of all the negative lenses included in the converter lens is defined.

Abstract: A zoom lens includes, in order from an object side to an image side, a first lens unit having negative refractive power, a second lens unit having positive refractive power, and a rear unit including one or more lens units. A distance between adjacent lens units changes during zooming. The rear unit includes a focus lens unit having positive refractive power and configured to move from the image side to the object side during focusing from infinity to a short-distance end. The first lens unit includes, in order from the object side to the image side, a first negative lens and a second negative lens. A predetermined condition is satisfied.

Abstract: A zoom lens consists of, in order from an object side to an image side, a first lens unit having a negative refractive power, a second lens unit having a positive refractive power, and a rear group including one or more lens units. Each distance between adjacent lens units changes during zooming. The rear group includes a focus lens unit having a positive refractive power that moves from the image side to the object side during focusing from an infinite distance object to a close distance object. A lens closest to an object in the focus lens unit has a shape with a concave surface on the object side. The following inequalities are satisfied. 1.20<fLP/fL2<3.20 ?3.00<fL1/fL2<?0.85 fLP represents a focal length of the focus lens unit, fL1 represents a focal length of the first lens unit, and fL2 represents a focal length of the second lens unit.

Abstract: A zoom lens includes a first lens unit having negative refractive power, a second lens unit having positive refractive power, an intermediate unit including one or more lens units, and a final lens unit having positive refractive power disposed closest to the image side. The first lens unit includes negative lenses G1, G2 and G3 disposed in this order from an object side to an image side. The final lens unit includes at least one negative lens and a positive lens disposed closest to the image side. The zoom lens satisfies predetermined inequalities.

Abstract: An optical system 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, an intermediate unit including one or more lens units, and a final lens unit having a negative refractive power. The second lens unit is moved toward an image plane, and a lens unit closest to the image plane in the one or more lens units included in the intermediate unit is moved toward the object in focusing from infinity to a short distance. The second lens unit satisfies a predetermined inequality.

Abstract: An optical system 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, an intermediate unit including one or more lens units, and a final lens unit having a negative refractive power. The second lens unit is moved toward an image plane, and a lens unit closest to the image plane in the one or more lens units included in the intermediate unit is moved toward the object in focusing from infinity to a short distance. The second lens unit satisfies a predetermined inequality.

Abstract: A converter lens includes three or more negative lenses and increases the focal length of an entire system, in which an average refractive index Ndave at the d-line (wavelength of 587.56 nm) of a material of all the negative lenses included in the converter lens is defined.

Abstract: An optical system includes a plurality of lenses and a diaphragm. The plurality of lenses consist of, in order from an object side to an image side, a first lens having a positive refractive power, a second lens having a positive refractive power, a third lens having a negative refractive power, a fourth lens, a fifth lens, and a sixth lens. The diaphragm is located between the first lens and the second lens. A predetermined condition is satisfied.

Abstract: A converter lens includes three or more negative lenses and increases the focal length of an entire system, in which an average refractive index Ndave at the d-line (wavelength of 587.56 nm) of a material of all the negative lenses included in the converter lens is defined.

Abstract: A zoom lens includes a first lens unit having negative refractive power, a second lens unit having positive refractive power, an intermediate unit including one or more lens units, and a final lens unit having positive refractive power disposed closest to the image side. The first lens unit includes negative lenses G1, G2 and G3 disposed in this order from an object side to an image side. The final lens unit includes at least one negative lens and a positive lens disposed closest to the image side. The zoom lens satisfies predetermined inequalities.

Abstract: An optical system 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, an intermediate unit including one or more lens units, and a final lens unit having a negative refractive power. The second lens unit is moved toward an image plane, and a lens unit closest to the image plane in the one or more lens units included in the intermediate unit is moved toward the object in focusing from infinity to a short distance. The second lens unit satisfies a predetermined inequality.

Abstract: An optical system includes, in order from object side, a first unit, a stop, a second unit, and a third unit. The first and second units are moved toward object side to increase respective intervals from the third unit for focusing from infinity to proximity. The first unit includes a negative lens and a positive lens arranged adjacent and on image side of the negative lens. The third unit consists of a positive lens (G3P) and a negative lens (G3N) arranged adjacent and on image side of the positive lens (G3P). An equivalent air length from a lens surface on image side of the negative lens (G3N) to an image plane when focused at infinity, and a distance on an optical axis from a lens surface on object side of a lens (G1F) arranged closest to object side, to the image plane when focused at infinity are appropriately set.

Abstract: Provided is a zoom lens consisting of: a positive first lens unit; a negative second lens unit; a positive third lens unit; and a rear lens group including at least one lens unit, wherein an interval between each pair of adjacent lens units is changed during zooming. The rear lens group includes a negative lens unit LR including at least one positive lens and at least one negative lens. The at least one negative lens includes a negative lens made of a material having a largest Abbe number of the at least one negative lens. Each of an extraordinary partial dispersion ratio of the material, distances of a lens surface on an image side of the lens unit LR to an image plane at a telephoto end and at a wide angle end, and a focal length of the lens unit LR is appropriately set.

Abstract: A converter lens includes three or more negative lenses and increases the focal length of an entire system, in which an average refractive index Ndave at the d-line (wavelength of 587.56 nm) of a material of all the negative lenses included in the converter lens is defined.

Abstract: An optical system includes, in order from object side, a first unit, a stop, a second unit, and a third unit. The first and second units are moved toward object side to increase respective intervals from the third unit for focusing from infinity to proximity. The first unit includes a negative lens and a positive lens arranged adjacent and on image side of the negative lens. The third unit consists of a positive lens (G3P) and a negative lens (G3N) arranged adjacent and on image side of the positive lens (G3P). An equivalent air length from a lens surface on image side of the negative lens (G3N) to an image plane when focused at infinity, and a distance on an optical axis from a lens surface on object side of a lens (G1F) arranged closest to object side, to the image plane when focused at infinity are appropriately set.

Abstract: Provided is a zoom lens consisting of: a positive first lens unit; a negative second lens unit; a positive third lens unit; and a rear lens group including at least one lens unit, wherein an interval between each pair of adjacent lens units is changed during zooming. The rear lens group includes a negative lens unit LR including at least one positive lens and at least one negative lens. The at least one negative lens includes a negative lens made of a material having a largest Abbe number of the at least one negative lens. Each of an extraordinary partial dispersion ratio of the material, distances of a lens surface on an image side of the lens unit LR to an image plane at a telephoto end and at a wide angle end, and a focal length of the lens unit LR is appropriately set.