An imaging lens substantially consists of a first lens-group, a stop and a second lens-group in this order from an object-side. The first lens-group substantially consists of three or less lenses including at least one negative lens and a positive lens. The second lens-group substantially consists of a 21st lens-group and a 22nd lens-group in this order from the object-side. The 21st lens-group substantially consists of three or less lenses and has positive refractive-power. The 22nd lens-group substantially consists of two lenses of a negative lens and a positive lens in this order from the object-side. Predetermined conditional formulas about distance on an optical-axis from a most-object-side lens surface in an entire system to an image-plane, maximum image height, distance on the optical-axis from a most-object-side lens surface in the first lens-group to a most-image-side lens surface in the second lens-group, and focal-length of the entire system are satisfied.

Imaging lens and imaging apparatus

A zoom lens system is provided that includes a compactly constructed focusing lens unit and that has a suppressed change in the image magnification at the time of movement of a focusing lens unit. The zoom lens system according to the present invention, in order from an object side to an image side, comprises: a first lens unit having positive optical power; a second lens unit having negative optical power; and at least two subsequent lens units, wherein the two lens units includes a lens unit A having positive optical power and a lens unit B arranged on the image side relative to the lens unit A, at the time of zooming, all lens units move in a direction along the optical axis so that intervals between the lens units vary, at the time of focusing, the lens unit B moves in a direction along the optical axis, and at the time of compensating image blur caused by vibration in the zoom lens system, either the entirety of a lens unit arranged on the object side relative to the lens unit A or a sub lens unit which is a part of a lens unit arranged on the object side relative to the lens unit A and is arranged on the image side therein moves in a direction perpendicular to the optical axis.

Zoom lens system, interchangeable lens apparatus and camera system

This zoom lens system is provided with: a first lens group that has negative power; a second lens group that has positive power; a third lens group that has negative power; and a fourth lens group that has positive power. During zooming, the first lens group, second lens group, and third lens group move along the optical axis. During focusing, the third lens group moves along the optical axis. The zoom lens system satisfies the conditions: 2.5 ≤ | (1 - (β 3T ) 2 ) × (β 4T ) 2 | ≤ 7.0 and 0.5 ≤ Bf W /f W ≤ 4.0 (β 3T being the lateral magnification of the third lens group at an infinite object distance at the telephoto end; β 4T the lateral magnification of the fourth lens group at an infinite object distance of the telephoto end; Bf W the back focus of the entire system at the wide angle end; and f W the focal length of the entire system at the wide angle end).

Zoom lens system, interchangeable lens device, and camera system

PROBLEM TO BE SOLVED: To provide a zoom lens system that is extremely thin when stored, has a wide field angle at the wide angle end and a zooming ratio of approximately three times, and to provide an imaging apparatus and a camera. SOLUTION: The zoom lens system includes a first lens group of negative power, a second lens group of positive power, and a third lens group of positive power. The first lens group has a first lens element of negative power which has a concave face on the image side and a second lens element of positive power which has a convex face on the object side. The second lens group comprises a first cemented lens element composed of two lens elements of powers of different signs, and a second cemented lens element composed of two lens elements of powers of different signs. For zooming, the first to third lens groups move along an optical axis. The zoom lens system satisfies the following conditions: 5.0 w 11 -1)×(n 12 -1)≥0.84 (wherein 3.2 T /f w , ω w >35, αi w represents an angle at which the principal light ray of the maximum height image at the wide angle end enters the imaging element, n 11 and n 11 each represent the refractive index of the second lens element, ω w represents a half field angle at the wide angle end, f T represents the focal distance of the entire system at the telephoto end, and f w represents the focal distance of the entire system at the wide angle end). The imaging apparatus and camera are also provided. COPYRIGHT: (C)2009,JPO&INPIT

Zoom lens system, imaging apparatus, and camera

A photographing optical lens assembly includes, in order from an object side to an image side, a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element and a sixth lens element. The first lens element with positive refractive power has an object-side surface being convex in a paraxial region. The second lens element has refractive power. The third lens element has positive refractive power. The fourth lens element has refractive power. The fifth lens element with positive refractive power has an object-side surface being convex in a paraxial region and an image-side surface being convex in a paraxial region. The sixth lens element with positive refractive power has an object-side surface being convex in a paraxial region and an image-side surface being concave in a paraxial region, and the image-side surface thereof has at least one inflection point.

Photographing optical lens assembly, image capturing unit and electronic device

A digital camera comprises an interchangeable lens unit and a camera body. The interchangeable lens unit is provided to form an optical image of a subject. A flash memory is configured to hold a correction coefficient table used to electrically correct distortion produced by the optical system. The camera body has a CCD image sensor, a correction coefficient acquisition part, an operation part, and a correction processor. The correction coefficient acquisition part is configured to acquire the correction coefficient table held in the flash memory. The operation part is configured to produce correction data by performing an interpolation operation or an extrapolation operation on the information obtained from the correction coefficient table. The correction processor is configured to correct distortion in the image data on the basis of information produced by the operation part.

Imaging device and camera body

A single focal length lens system comprising at least a positive first lens unit and a second lens unit, wherein the first lens unit includes a first sub lens unit E which successively comprises a negative lens element A, a positive lens element B, a negative lens element C and a positive lens element D, a second sub lens unit comprising at least one lens element is a focusing lens unit in the second lens unit, and the conditions: 1.0<|f W /f A |<2.2, 0.5<f W /f B <2.0, 0.5<|f W /f C |<1.7, and 0.5<f W /f D <1.8 (f W : focal length of the lens system, f A : focal length of the lens element A, f B : focal length of the lens element B, f C : focal length of the lens element C, f D : focal length of the lens element D) are satisfied.

Single focal length lens system, interchangeable lens apparatus and camera system

The present zoom lens system comprises a plurality of lens units including at least: a front lens unit having negative optical power; and a rear lens unit having positive optical power, arranged on the image side of the front lens unit, and composed of a plurality of lens elements; wherein magnification change is performed by changing an interval between the individual lens units, wherein the rear lens unit comprises: a rear A lens unit capable of moving in a direction perpendicular to an optical axis; and a rear B lens unit that is arranged on the image side of the rear A lens unit and that can move in an optical axis direction in such a manner that an interval relative to the rear A lens unit in the optical axis direction is changed, and wherein focusing adjustment during variation of the object distance is achieved by changing the interval between the rear A lens unit and the rear B lens unit.

Zoom lens system and imaging optical device employing the same

It is possible to obtain an imaging lens system having a small size for easy carrying and a preferable image performance corresponding to a high number of pixels. The imaging lens system is intended for forming an optical image of an object on a light reception surface of a solid imaging element. The imaging lens system includes an aperture diaphragm and three lens elements arranged in this order from the object side: a first lens element as a both-side aspherical lens having a positive power and a convex surface at the image side, a second lens element as a both-side aspherical meniscus lens having a negative power and a concave shape at the object side, and a third lens element as a both-side aspherical meniscus lens having a positive power and a convex shape at the object side. The lens elements satisfy the following conditions: 1.5 < |fd/f2d| < 2.3 0.5 < |fd/f3dv < 1.1 -2.2 < (r21 + r22)/(r21 - r22) < -1.3 2.1 < (r31 + r32)/(r31 - r32) < -1.7

Imaging lens, imaging unit and optical device

Compact and lightweight zoom lens systems having less aberration fluctuation in association with focusing, lens barrels, interchangeable lens apparatuses, and camera systems are provided. The zoom lens system comprises: a first lens unit having positive optical power; a first focusing lens unit which is located on an image side relative to the first lens unit, has negative optical power, and moves along an optical axis in zooming and focusing; and a second focusing lens unit which is located on the image side relative to the first focusing lens unit, has positive optical power, and moves along the optical axis in the zooming and the focusing, and satisfies the condition: |d 2T /d 1T |<1.0 (d 1T : an amount of movement of the first focusing lens unit in focusing at a telephoto limit, d 2T : an amount of movement of the second focusing lens unit in focusing at a telephoto limit).

Kyoichi Miyazaki

Papers

Imaging device and camera body

Single focal length lens system, interchangeable lens apparatus and camera system

Zoom lens system and imaging optical device employing the same

Imaging lens, imaging unit and optical device

Zoom lens system, lens barrel, interchangeable lens apparatus and camera system