NOISE REDUCTION METHOD AND SYSTEM FOR TOUCH DETECTION DEVICE

• US 20140028620A1
• Filed: 09/27/2013
• Published: 01/30/2014
• Est. Priority Date: 03/28/2011
• Status: Active Grant

• Current Assignee: Shenzhen Goodix Technology Co., Ltd.
• Original Assignee: Shenzhen Huiding Technology Co., Ltd.
• Inventors: DENG, Gengchun, CHEN, Xiaoxiang
• Granted Patent: US 9,946,378 B2
• Time in Patent Office: Days
• US Class Current: 345/174
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/04182 Filtering of noise external to the device and not generated by digitiser components
• CPC Class Codes: G06F 3/0445 using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer

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.

Claims

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, 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 C41, setting distribution scales for statistics of detection data;

step C42, calculating the distribution statistics of a group of detection data obtained at step B;

step C43, identifying a most concentrated detection data distribution scale; and

step C44, calculating an average of the data in the most concentrated scale, the obtained average being considered as the desired DC offset component.

2. A noise reduction system for a touch detection device, touch detection nodes of the touch detection device being divided into one or more groups, the noise reduction system comprising:

a sampling unit configured to perform a synchronous sampling on the touch detection nodes belonging to the same group and store the sampling data;

a differential value calculating unit configured to compare each sampling data against a corresponding reference data to calculate a differential data to replace a corresponding original sampling data;

a noise calculating unit configured to calculate statistics of the replacing detection data obtained by the differential value calculating unit to screen out, according to a predetermined screening condition, valid data to calculate a DC offset component indicative of a noise ingredient; and

a noise filtering unit configured to obtain noise-filtered detection data by subtracting the DC offset component obtained by the noise calculating unit from each detection data calculated by the differential value calculating unit;

wherein the noise calculating unit comprises;

a distribution scale setting module configured to set distribution scales for statistics of detection data;

a distribution scale statistics module configured to calculate the distribution statistics of a group of replacing detection data obtained by the differential value calculating unit; and

a DC offset component determining module configured to calculate an average of data in a most concentrated data distribution scale obtained by the distribution scale statistics module, the average obtained being considered as the desired DC offset component.

3. A touch terminal comprising a touch detection device, the touch detection device comprising:

a touch sensor unit; and

a touch controller unit coupled to the touch sensor unit, wherein the touch controller unit comprises a noise reduction system, touch detection nodes of the touch detection device being divided into one or more groups, the noise reduction system comprising;

a sampling unit configured to perform a synchronous sampling on the touch detection nodes belonging to the same group and store the sampling data;

a differential value calculating unit configured to compare each sampling data against a corresponding reference data to calculate a differential data to replace a corresponding original sampling data;

a noise calculating unit configured to calculate statistics of the replacing detection data obtained by the differential value calculating unit to screen out, according to a predetermined screening condition, valid data to calculate a DC offset component indicative of a noise ingredient; and

a noise filtering unit configured to obtain noise-filtered detection data by subtracting the DC offset component obtained by the noise calculating unit from each detection data calculated by the differential value calculating unit;

wherein the noise calculating unit comprises;

a distribution scale setting module configured to set distribution scales for statistics of detection data;

a distribution scale statistics module configured to calculate the distribution statistics of a group of replacing detection data obtained by the differential value calculating unit; and

a DC offset component determining module configured to calculate an average of data in a most concentrated data distribution scale obtained by the distribution scale statistics module, the average obtained being considered as the desired DC offset component.