Patent ID: 6365888
Filing Date: 2002-04-02
Classification: G06K

Abstract:
A method for capacitive image acquisition, which comprises:a) dividing an area to be acquired as an image in a grid-shaped array into pixels assigned an assembly of electrical conductors comprising, for each pixel, a measuring conductor and a shielding conductor; b) placing the area to be acquired as an image opposite the measuring conductors, so that a capacitance is present between the pixels and the measuring conductors in each case dependent on the relevant pixel; c) at each pixel, connecting the measuring conductor and the shielding conductor to the same electrical potential and disconnecting from the potential; d) at each pixel, discharging a charge present on one of the measuring conductor and the shielding conductor onto a respective collecting capacitor, and simultaneously compensating a potential difference between the measuring conductor and the shielding conductor; and e) repeating steps c and d until the charges collected on the collecting capacitors have at least a value predetermined to be sufficient for a separate measurement of each collecting capacitor.