Automatic image rotation compensation circuit and method

摘要

An automatic image rotation compensation circuit includes: a terrestrial magnetic field detecting unit for detecting horizontal and vertical terrestrial magnetic fields of a place where a display device is installed; an amplifying unit for amplifying the horizontal and vertical terrestrial magnetic field values detected by the terrestrial magnetic field detecting unit; an analog-to-digital converting unit for converting the analog terrestrial magnetic field values amplified by the amplifying unit into digital signals; a memory for storing image compensation reference values corresponding to various terrestrial magnetic field values; a microcomputer for receiving the digital terrestrial magnetic field values from the analog-to-digital converting unit and reading compensation values corresponding to the terrestrial magnetic field values; a digital-to-analog converting unit for converting the digital signals from the microcomputer into analog signals; and a deflection controller for performing a differential amplification on the signals transmitted from the digital-to-analog converting unit and changing a current flowing through rotation coils to control a tilt.