Patent ID: 8570293

Claim:
A noise reduction method for a touch detection device, wherein touch detection nodes of the touch detection device are divided into one or more groups and the noise reduction method comprises: step A, performing a synchronous sampling on the touch detection nodes in one same group and storing the sampling data; step B, comparing each sampling data against a corresponding reference data to calculate a differential data which, as a detection data, replaces a corresponding original sampling data; step C, calculating statistics of the replacing detection data obtained at step B to screen out, according to a predetermined screening condition, valid data to calculate a DC offset component indicative of a noise ingredient; and step D, obtaining noise-filtered detection data by subtracting the DC offset component obtained at step C from each detection data obtained at step B; wherein step C further comprises: step C21, setting a threshold value to determine the validity of a data; and setting distribution scales for statistics of detection data distribution; step C22, calculating the distribution statistics of a group of detection data obtained at step B; step C23, identifying a most concentrated data distribution scale and a second most concentrated data distribution scale; step C24, determining whether the amplitude of an average of the data in the most concentrated data distribution scale is larger than the threshold value; step C25, if the determination result of step C24 is yes, further determining whether the amplitude of an average of the data in the second most concentrated data distribution scale is less than the amplitude of the average of the data in the most concentrated data distribution scale; step C26, if the determination result of step C25 is yes, considering the average of the data in the second most concentrated data distribution scale as the DC offset component; and step C27, if either the determination result of step C24 or the determination result of step C25 is no, considering the average of the data in the most concentrated data distribution scale as the DC offset component.