Patent ID: 6462810
Filing Date: 2002-10-08
Classification: G01C

Abstract:
A surveying system, comprising a collimation target for projecting a guide light, a survey instrument main unit for receiving and detecting said guide light projected from said collimation target, a horizontal rotating mechanism for rotating the survey instrument main unit in a horizontal direction in order to direct said survey instrument main unit to said collimation target, a control unit for controlling said horizontal rotating mechanism, a rough direction detecting unit capable to detect said guide light from all horizontal directions, and a precise direction detecting unit for detecting said guide light from the collimating direction of said survey instrument main unit, wherein said precise direction detecting unit comprises a photodetection sensor, a photodetection limiting means for limiting a photodetection range in a horizontal direction of said photodetection sensor in a range of a predetermined angle, and a cylinder lens curved in an arcuate shape in a vertical direction for making the photodetection range larger in a vertical direction and for converging said guide light at a position of said photodetection limiting means, and wherein said control unit controls said horizontal rotating mechanism so that a direction of said survey instrument main unit is approximately aligned to said collimation target based on a result of a detection from said rough direction detecting unit, and so that the direction of said survey instrument main unit precisely collimates said collimation target based on a result of a detection from said precise direction detecting unit.