Noise reduction method and system for touch detection device

Patent metadata

Field	Value
Publication number	US-9946378-B2
Application number	US-201314038791-A
Country	US
Kind code	B2
Filing date	Sep 27, 2013
Priority date	Mar 28, 2011
Publication date	Apr 17, 2018
Grant date	Apr 17, 2018

Abstract

Noise reduction method and system for a touch detection device are disclosed. The noise reduction method includes: 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 to screen out 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 from each detection data.

First claim

What is claimed is:

1. 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 41 , setting a plurality of mutually exclusive data ranges each having a preset upper limit and a preset lower limit;
step C 42 , comparing each detection data of a group of detection data obtained at step B with the preset upper limit and the preset lower limit of each of the plurality of mutually exclusive data ranges to determine which data range each detection data of the group of detection data falls in;
step C 43 , calculating the number of detection data in each data range to identify a most concentrated data range in which the number of the detection data fall is greatest; and
step C 44 , calculating an average of all the detection data in the most concentrated data range, the obtained average being considered as a DC offset component; and
step D, obtaining noise-filtered detection data by subtracting the DC offset component obtained at step C 44 from each detection data obtained at step B.

Assignees

• Shenzhen Goodix Tech Co Ltd

Inventors

• Deng Gengchun
• Chen Xiaoxiang

Classifications

• G06F3/0412 Primary

  Digitisers structurally integrated in a display · CPC title

• G06F3/044

  by capacitive means · CPC title

• G06F3/0418

  for error correction or compensation, e.g. based on parallax, calibration or alignment · CPC title

• G06F3/04182 Primary

  Filtering of noise external to the device and not generated by digitiser components · CPC title

• G06F3/0445

  using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer · CPC title