Patent ID: 6541986
Filing Date: 2003-04-01
Classification: G01B,G01D

Abstract:
A sensor for the capacitive measurement of film thicknesses, comprising:a rotating drum which rolls along a film and has several measuring capacitors which are distributed in a circumferential direction of the drum, each measuring capacitor including plates of which are disposed in a peripheral surface of the drum, so that capacitance of each said measuring capacitor is effected by a thickness of the film, and each measuring capacitor has its own oscillator assigned to itself in such a manner, that geometry of an oscillating circuit, formed by the measuring capacitor and the respective oscillator, is the same for all measuring capacitors, a transmitter for transmitting a measurement signal from the rotating drum to a stationary part, and oscillators which are integrated in the drum and each of which generates a frequency signal which depends on the capacitance of the respective measuring capacitor.