MEASURING DEVICE

To provide a measuring device with which it is possible to facilitate assembling and adjustment without the need for an elaborate adjustment of the fitted position of a light source and the axis alignment of an enlargement lens.SOLUTION: Provided is a measuring device comprising a light source for emitting measurement light, a light receiving unit for receiving reflected light of the measurement light from the object to be measured, the measuring device measuring the distance to the object to be measured, on the basis of the reflected light received by the light receiving unit. The measuring device includes an aperture member for narrowing the beam of measurement light from the light source, the aperture member including a center light permeable part arranged on the optical axis of the light source and a light permeable band part for forming a plurality of light permeable bands arranged in the periphery of the center light permeable part. The emitted beam of measurement light is expanded to a desired angle of aperture by interference due to diffraction at the time measurement light passes through the center light permeable part and the light permeable band part.SELECTED DRAWING: Figure 4 【課題】光源の取付位置や拡大レンズ系の軸合わせ等の細かな調整をする必要がなく、組立や調整を簡易なものにできる測定装置を提供する。【解決手段】測定光を発する光源と、測定光の被測定物からの反射光を受ける受光部とを備え、受光部が受光した反射光に基づいて被測定物までの距離を測定する測定装置において、光源からの測定光の光束を絞る絞り部材を備え、絞り部材は、光源の光軸上に配置された中央透光部、及び中央透光部の周囲に配置された複数の透光帯部を形成する遮光帯部を備え、測定光が中央透光部及び透光帯部を透過するときの回折による干渉により、射出する測定光の光束を所望の開き角に拡大する。【選択図】図４