Patent ID: 6049422
Filing Date: 2000-04-11
Classification: A61B,G02B

Abstract:
An optical system for non-flexible endoscopes comprising: an illumination optical system and an observation optical system which are disposed in an insert section, wherein said observation optical system comprises, in order from a side of a tip, at least an objective optical system and a single relay cycle type relay optical system, and satisfies the following conditions (1) and (2):L/D1<20 (1)0.7<D2/D3<0.9 (2)wherein the reference symbol L represents a distance as measured from a tip of the objective optical system to an image formed by the objective optical system, the reference symbol D1 designates an outside diameter of a lens component in the objective optical system whichever has a largest outside diameter, the reference symbol D2 denotes an outside diameter of a lens component in the relay optical system whichever has a largest outside diameter and the reference symbol D3 represents an outside diameter of the insert section.