Patent ID: 8648830

Claim:
A method for noise reduction in a digitizer, the digitizer comprising a plurality of detecting elements spread over a sensing surface for detecting an electromagnetic signal and finger touch, the method comprising: sampling at least two detecting elements from the plurality of detecting elements substantially simultaneously to obtain output from each of the at least two detecting elements; selecting as a candidate carrier of mere noise, at least one detecting element from the at least two detecting elements providing output above a defined threshold in at least one frequency used for finger touch detection; selecting at least one other detecting element of the at least two detecting elements as a candidate carrier of a stylus signal providing output in a known frequency of emission of a stylus; selecting a frequency for estimating a noise level at the known frequency of emission of the stylus; determining an output level provided by each of the at least two detecting elements in the selected frequency and in the known frequency of emission of a stylus; and reducing the output level provided by the at least one other detecting element selected as the candidate carrier of the stylus signal in accordance with the output level on the at least one detecting element selected as the candidate carrier of mere noise.