Zoom Lens and Image Pickup Apparatus Using the Same

• Main Authors: YOKOYAMA KEITARO, TAKAHASHI TOSHIO, KAWAMURA KAZUTERU, NAITO AKIKO
• Format: Patent
• Language: English
• Published: 07.01.2016
• Subjects: ELECTRIC COMMUNICATION TECHNIQUE; ELECTRICITY; OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS; OPTICS; PHYSICS; PICTORIAL COMMUNICATION, e.g. TELEVISION

A zoom lens comprises four lens unit, and at the time of zooming, each of a distance between a first positive lens unit and a first negative lens unit and a distance between a second negative lens unit and a second positive lens unit changes, and a distance between the first positive lens unit and the second negative lens unit widens more at the telephoto end than at the wide angle end, and the first positive lens unit includes an object-side sub-lens unit and an image-side sub-lens unit, and an aperture stop is disposed between the object-side sub-lens unit and the image-side sub-lens unit, and the first negative lens unit includes a negative lens and a positive lens, and a refracting surface nearest to an image in the first negative lens unit is concave toward the image side, and a refracting surface nearest to an object in the second positive lens unit is concave toward the object side, and a refracting surface nearest to the image in the second positive lens unit is convex toward the image side, and the zoom lens satisfies predetermined conditional expressions.