Journal of Institute of Control, Robotics and Systems (제어로봇시스템학회논문지)

Institute of Control, Robotics and Systems (제어로봇시스템학회)
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Pointing position detection of capacitive touch screen panel using phase-difference method

위상차 방식을 사용한 용량방식 터치 스크린 패널의 접촉 위치 검출

  • Jo, Yeong-Cheol (Dept.of Electric Engineering, Seoul National University) ;
  • Jang, Rae-Hyeok (Dept.of Computer Engineering, Seoul National University) ;
  • Gwon, Uk-Hyeon (Dept.of Electric Engineering, Seoul National University)
  • 조영철 (서울대학교 전기공학부) ;
  • 장래혁 (서울대학교 컴퓨터 공학과) ;
  • 권욱현 (서울대학교 전기공학부)
  • Published : 1998.06.01
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Abstract

This paper describes a contact position detection method of a capacitive touch screen panel. The proposed method is composed of a circuited compensating algorithm generating an output signal having phase difference to an input signal associated with contact position, converts both input and output signals into digital waveform (5V logic), and calculates the phase difference. Finally, position information with the phase difference is obtained by using a low-cost microprocessor, which is convenient to compensate non-linearity error. The proposed method, that computes phase difference directly, has advantages in feasibility and cost because it minimizes the use of analog devices; rather, it utilizes, cost effective digital circuit. Analytical results are also given.

Keywords

References

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