OPTICAL DEVICE, AND METHOD OF MEASURING THE DIMENSION OF OBJECT USING OPTICAL DEVICE

摘要

A device and a method for measuring the dimensions of a remote object, for example concrete crack, without using a high-place work vehicle or a ladder. An optical device (e.g. a distance measuring device (10)) used for this is provided with a telescope (16) having a projection plate (46). The projection plate (46) is provided with a plurality of reference scales (52) used for comparison with the size (W) of the image (C') of an object (C) projected onto the projection plate (46). The size of the object can be measured using the size of the object image measured with the reference scales (52) and a distance (a distance from a reference point P0 to the object) measured with the distance measuring unit (20) of the optical device.