PROBLEM TO BE SOLVED: To provide an optical scanning device which is not negatively affected by reduction in mechanical strength of a mirror surface caused by recesses evenly distributed on a back surface of a mirror.SOLUTION: An optical scanning device has a first beam extending in a first direction and a first reflective part coupled with one end of the first beam and configured to be rotatable about the first beam. The first reflective part has a reflective surface for reflecting light and a back surface on a side opposite the reflective surface, and recesses formed by selectively removing portions of the back surface, and is configured such that volume of the recesses gradually increases from a first axis of the first reflective part, extending in the first direction through the first beam, toward edges of the first reflective part that are farthest from the first axis.SELECTED DRAWING: Figure 4COPYRIGHT: (C)2017,JPO&INPIT【課題】ミラー裏面に一様に凹部を設けてもミラー面の機械的強度の低下が問題とならない光走査装置を提供する。【解決手段】第1方向に延伸する第1の梁部と、第1の梁部の一端に接続され、第1の梁部を回転軸として回転することができる第1の反射部とを備える光走査装置において、第1の反射部は、光を反射する反射面と、反射面の反対側に位置する裏面と、裏面の一部が選択的に除去された凹部とを有し、第1の梁部を通過して第1方向に伸びる第1の反射部の第1の軸部から、第1の軸部から最も離れた第1の反射部の端部にかけて、凹部の体積が増加するように構成する。【選択図】図4
