SIZE CONVERSION ADAPTER, LENS FOR CAMERA AND CAMERA BODY USING SAME SIZE CONVERSION ADAPTER, AND CAMERA

摘要

PROBLEM TO BE SOLVED: To uses a lens, used for a camera equipped with a 1/3-inch type imaging device, for a camera equipped with a 1/2-inch type imaging device by using a conversion adapter composed of two negative and positive lenses. SOLUTION: The size conversion adapter 2 has a negative lens 21 and a positive lens L22 in order from an object side and satisfies a conditional inequality (1) of 0.3<¾F1/F2¾<1 (where F1 is the focal length of the negative lens and F2 is the focal length of the positive lens). The size conversion adapter 2 is arranged on the image side of a lens body 1 detachably or in one body to satisfy a conditional inequality (2) of 0.01f<1 (where L is the air gap from the image-side surface peak of the lens body to the object-side surface peak of the size conversion adapter and Bfis the composite back focus of the lens body and size conversion adapter) to obtain a lens for camera. Here, the size conversion adapter 2 and camera body 3 may be constituted mutually detachably or in one body. COPYRIGHT: (C)2005,JPO&NCIPI