Patent ID: 8561455

Claim:
A sensor head for measurement of a film, comprising: a guide surface for the film, at least one sensor element integrated in the guide surface for measuring a property of the film, and a generator for generating an air cushion between the guide surface and the film, said generator comprising: a system for supplying a pressure medium, and a guide member made of a porous material and forms at least a part of the guide surface and is adapted to distributedly discharge the pressure medium into the air cushion, the guide member having a channel system formed by at least one channel that is recessed relative to the guide surface, that opens to an outside of said guide member, and that divides the guide surface into a plurality of fields in a manner such that the pressure medium discharged into the air cushion is separated into divided flow rates which substantially eliminates accumulation of the pressure medium in the air cushion to prevent distortion of the film, and the plurality of fields being one of: disconnected, and connected only by narrow lands, said channel system being configured for draining the pressure medium from the air cushion.