| 摘要 |
PROBLEM TO BE SOLVED: To acquire an image having an excellent aberration correction performed even when an image rotator is arranged on an imaging side.SOLUTION: A relay optical system 1 is provided that has: a prism; a front group lens; an intermediate image formation position; an image rotator R1; and a rear group lens that, in order from an object side to an image side, are arranged between an objective optical system provided at a tip part of an insertion part of an endoscope 2 and imaging means photographing an image to be sent from the objective optical system, and regarding an aberration correction amount of the front group lens satisfies the following conditional expression (1)... 0.0138<|(AXCf-AXCc)/D|≤0.0313, where AXCf denotes a longitudinal chromatic aberration amount (mm) on a F-line, AXCc denotes a longitudinal chromatic aberration amount (mm) on a C-line, and D denotes an optical path length (mm) of the image rotator. |
