ZOOM LENS AND PHOTOGRAPHING DEVICE HAVING THE SAME

• Main Authors: USUI FUMIAKI, FUKAMI SEIJI
• Format: Patent
• Language: English
• Published: 22.04.2004
• Edition: 7
• Subjects: OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS; OPTICS; PHYSICS

PROBLEM TO BE SOLVED: To provide a zoom lens and a photographing device which display a high optical performance throughout a variable magnification range even in vibration-proofing and have an entire mechanism made small-sized and lightweight. SOLUTION: The zoom lens has a first group having a positive refractive power, a second group which is moved when varying magnifications and has a negative refractive power, a third group which is moved when varying magnifications and has a negative refractive power, and a fourth group which is fixed when varying magnifications and has a positive refractive power, which are arranged in order from the object side, and the fourth group has a vibration-proof lens group having a negative refractive power, and the vibration-proof lens group has a function of displacing an image by moving so as to have a component in the direction perpendicular to an optical axis, and the fourth group has a focal length conversion optical system which can be inserted to and removed from the optical axis and changes the focal length of the entire system, on the image surface side of the vibration-proof lens group. COPYRIGHT: (C)2004,JPO