PROBLEM TO BE SOLVED: To achieve downsizing and cost reduction in an endoscope.SOLUTION: An endoscope includes an image pickup device 33 whose imaging surface 41 is covered with a device cover glass 43, a lens 93 which forms an image from incident light from a subject on the imaging surface 41, and an adhesive resin 37 for fixing the lens 93 and the device cover glass 43 on a distal end part 15 of an insertion part. The lens 93 is formed into a rectangular shape in an outer shape with four corners of a right angle and comprises a single lens having a flat first surface on a subject side and a convex second surface on an imaging side. The image pickup device 33 is square in the outer shape, and a length of a side is longer than or identical with the longest side of the lens 93. An optical element part having a convex curved surface part bulging in the form of a spherical surface for constituting a lens surface of a convex surface in a central part and an edge part having a flat adhesive surface at an end surface in a peripheral edge part are integrally formed at the imaging side of the lens.SELECTED DRAWING: Figure 24【課題】内視鏡において小型化、コスト低減を図る。【解決手段】内視鏡は、挿入部の先端部１５に、撮像面４１が素子カバーガラス４３によって覆われる撮像素子３３と、被写体からの入射光を撮像面４１に結像するレンズ９３と、レンズ９３と素子カバーガラス４３とを固定する接着用樹脂３７と、を有し、レンズ９３は、外形形状が四隅の直角な四角形に形成され、被写体側の第１面が平面、撮像側の第２面が凸面を有する単一レンズにより構成され、撮像素子３３は、外形状が正方形であり、辺の長さがレンズ９３の最も長い辺よりも長いか又は同一で構成され、レンズの撮像側において、凸面のレンズ面を構成する略球面状に隆起した凸曲面部を持つ中央部の光学素子部と、端面が平面の接着面を有する周縁部のコバ部とが一体的に形成されている。【選択図】図２４
