PROBLEM TO BE SOLVED: To provide an endoscope capable of reliably and easily guiding a treatment instrument, which is passed through a treatment instrument insertion channel and led out from a distal end opening, to the central part of an observation object.SOLUTION: The endoscope comprises: an insertion part extended to the distal side of an operation part a distal end component member 20 arranged in the distal side of the insertion part an imaging optical system 30 with an effective angle of view θ set thereto, the imaging optical system being arranged so as to be orthogonal to a surface 31f of a most distally positioned observation window 31 relative to a longitudinal central axis 20a of the distal end component member 20, and the observation window being arranged in a hole for imaging optical system 23 having a central axis 23a parallel to the longitudinal central axis 20a and a treatment instrument insertion channel hole 24 which includes a first hole 25 having a first axis 24a parallel to the longitudinal central axis 20a and a second hole 26 having one side crossing the first axis 24a and the other side having a second axis 24b extending to within an observation depth 30L of an observation optical system 30, and which has a distal end opening 26m, an opening of the second hole 26 to be used as a lead-out opening for a treatment instrument, the distal end opening being more distally provided than the surface 31f of the observation window 31.SELECTED DRAWING: Figure 4COPYRIGHT: (C)2016,JPO&INPIT【課題】処置具挿通チャンネルを通過して先端開口から導出される処置具を確実且つ容易に観察対象中心部に導ける内視鏡を提供する。【解決手段】内視鏡は、操作部の先端側に延設された挿入部と、挿入部の先端側に設けられた先端構成部材20と、先端構成部材20の長手中心軸20aに平行な中心軸23aを有する撮像光学系用孔23に配設される、最先端に位置する観察窓31の表面31fを長手中心軸20aに対して直交する位置関係に配置した、有効画角を角度θに設定した撮像光学系30と、長手中心軸20aに平行な第1軸24aを有する第1孔25及び第1軸24aに交差する一方側と他方側が観察光学系30の観察深度30L内に向かう第2軸24bを有する第2孔26を備え、観察窓31の表面31fより先端側に第2孔26の開口であって処置具導出口となる先端開口26mを有する処置具挿通チャンネル孔24と、を具備する。【選択図】図4
