Patent attributes
A surveying instrument comprises a distance measuring unit configured to measure a distance to an object to be measured, an optical axis deflector configured to deflect a distance measuring light, a measuring direction image pickup module configured to acquires an observation image and an arithmetic control module, wherein the arithmetic control module is configured to continuously cut out sighting images around a tracking point set in the observation image, to set a first cutout sighting image as a reference sighting image, to calculate a movement amount of the sighting image with respect to the reference sighting image by an image matching of the reference sighting image and the sighting image and to control the optical axis deflector based on a calculation result in such a manner that the tracking point is positioned at a center of the sighting image.
