发明授权
- 专利标题: Error compensation for multi-touch surfaces
- 专利标题(中): 多点触摸表面的误差补偿
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申请号: US11650204申请日: 2007-01-03
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公开(公告)号: US07692638B2公开(公告)日: 2010-04-06
- 发明人: Brian Richards Land , Steve Porter Hotelling
- 申请人: Brian Richards Land , Steve Porter Hotelling
- 申请人地址: US CA Cupertino
- 专利权人: Apple Inc.
- 当前专利权人: Apple Inc.
- 当前专利权人地址: US CA Cupertino
- 代理机构: Morrison & Foerster LLP
- 主分类号: G09G5/00
- IPC分类号: G09G5/00
摘要:
Normalization of the built-in DC offset error in each analog channel is disclosed to reduce image distortion in multi-event (multi-touch or multi-hover) sensor panels. By eliminating the component-dependent offset error from each analog channel, each analog channel will generate approximately the same output value for a given dynamic input signal. Normalization can include “phantom row” compensation, which involves measuring the static output value of each analog channel when no stimulus is applied to any row of a multi-event sensor panel, and subtracting this value out of any subsequent output value generated by the analog channel. Normalization can also include DAC offset compensation, which involves setting the offset compensation voltage of each analog channel to some fraction of its normal value, measuring the output of the analog channel over temperature, determining a temperature coefficient, and adjusting any subsequent output value generated by the analog channel to account for this drift.
公开/授权文献
- US20080158184A1 Error compensation for multi-touch surfaces 公开/授权日:2008-07-03
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