| 摘要 |
An electric optical distance meter is provided that makes an input power level of a reference light entering a light receiving device via an internal optical path comparable between low and high reflectivity targets. The electric optical distance meter has a shutter 50 for switching between an external optical path Po, through which a distance measuring light emitted by a light source is placed to and from a target, and the internal optical path Pi is placed from the light source to the light receiving device, where the shutter has: a rotating axis 55; blocking plates 56 which are arranged at two locations symmetric with respect to the rotating axis, and alternately block the respective distance measuring lights L entering the external optical path and the internal optical path; and an attenuation plate 57 which is placed at one of the two locations where the blocking plates are not arranged and between the blocking plates, and attenuates the distance measuring light entering the internal optical path when the target is of a low reflectivity.
|
