Aiming at centering deviation problem

the effect law of theodolite’s centering deviation on azimuth measurement error is analyzed

and the error compensation model is setup.The value and direction of centering deviation are detected by CCD fixed on the surface below theodolite

and the azimuth measurement error by centering deviation can be compensated by the error model.The error of the model itself is studied.It reveals that the model precision can meet the need of high-precision angle measurement of theodolite.The presented compensation method

the measuring distance limitation is reduced for the same precision compared with the traditional method

and the automation degree of azimuth angle measurement of theodolite is also improved and the operation time is reduced.