Bright relay optical system, and optical system for rigid endoscope and rigid endoscope using the same

摘要

A relay optical system includes an object-side lens which is disposed nearest to an object, an image-side lens which is disposed nearest to an image, and a cemented lens having a positive refractive power. The object-side lens has a positive refractive power and is disposed such that a convex surface is directed toward an object side. The image-side lens has a positive refractive power and is disposed such that a convex surface is directed toward an image side. A plurality of the cemented lenses is disposed between the object-side lens and the image side lens and the following conditional expression (1) is satisfied:0.04I>Gce/Drel<0.4  (1)where,Gce denotes the smallest of intervals of adjacent cemented lenses, andDrel denotes a distance from an object plane up to an image plane of the relay optical system.