PROBLEM TO BE SOLVED: To provide an endoscope for achieving a configuration capable of surely blocking light from an illumination unit to an observation optical system at a distal end face on a distal end part and supplying illumination light from the distal end part to an adapter without light quantity loss, while reducing a diameter of the distal end part.SOLUTION: An endoscope comprises: a distal end face 11s an observation optical system 30 in which an observation lens 30a is exposed at the distal end face 11s so as to be flush with the distal end face 11s a light guide 35 whose emission end face 35s is exposed at the distal end face 11s so as to be flush with the distal end face 11s and observation lens 30a a recessed groove 20 which is positioned between the observation lens 30a and emission end face 35s at the distal end face 11s, and is linearly formed so as to connect two parts on the outer periphery of the distal end face 11s and a rod-like light shielding member 25 which is fitted into the recessed groove 20, and has an open shape for blocking incidence of illumination light emitted from the emission end face 35s on the observation lens 30a, when an adapter 1 is attached to a distal end of an insertion part.COPYRIGHT: (C)2015,JPO&INPIT【課題】先端部の先端面における照明ユニットから観察光学系への遮光を確保でき、さらには先端部からアダプタに光量ロス無く照明光を供給できる構成を先端部の小径化とともに実現できる内視鏡を提供する。【解決手段】先端面11sと、観察用レンズ30aが先端面11sに該先端面11sと同一面となるよう露出する観察光学系30と、出射端面35sが先端面11sに該先端面11s及び観察用レンズ30aと同一面となるよう露出するライトガイド35と、先端面11sにおいて、観察用レンズ30aと出射端面35sとの間に位置するとともに先端面11sの外周間を繋ぐよう直線状に形成された凹溝20と、凹溝20に嵌入された、挿入部の先端にアダプタ1が装着された際、出射端面35sから照射された照明光が観察用レンズ30aに入光するのを遮光する開形状を有する棒状の遮光部材25とを具備している。【選択図】図5
