SURVEYING INSTRUMENT AND PLUMBING DEVICE FOR PLUMBING SURVEYING INSTRUMENT

Disclosed is a surveying instrument and a plumbing device for plumbing the surveying instrument. The plumbing device is capable of calculating dislocations x and y of the surveying instrument from a datum point, and the instrument height H of the surveying instrument. The plumbing device comprises optical means for forming an image of a target placed at a survey station to indicate the survey station, photoelectric means for receiving an image of the target and providing an image signal, and processing means for calculating instrument height corresponding to distance between a reference point on the surveying instrument and the target, and dislocations of the reference point from the survey station.