VELOCITY SENSOR AND ITS ELECTRODE STRUCTURE AND ITS SIGNAL DETECTION METHOD AND ITS PRODUCTION METHOD

PURPOSE:To realize an ultrasmall velocity detector which has high detection accuracy and is very stable for environmental temperature and shock and easy for production. CONSTITUTION:A velocity sensor utilizes a torsion tuning fork type crystal vibrator 12 and has a special cut angle and special dimensions and structure with common or separated exciting electrode and velocity detection electrode. A signal detection circuit is constituted of an oscillation circuit, a phase comparison circuit, a recovery circuit and a differential signal circuit. The sensor is produced with a photolithography technique The conventional photolithography technique production line can be used as it is and detection circuit is realized with C-MOS IC and thus, a velocity sensor with high accuracy, low power consumption and low price with the small size like a tuning fork type crystal vibrator for a wrist watch can be realized.