Title:
CAPACITANCE DETECTION DEVICE
Document Type and Number:
WIPO Patent Application WO/2023/223625
Kind Code:
A1
Abstract:
Provided is a capacitance detection device that can suppress the effects of drift in capacitance value caused by environmental changes in temperature, humidity, and the like. A capacitance detection device according to the present invention includes a sensor electrode, a shield electrode that is arranged near the sensor electrode, a first voltage output unit that outputs a first alternating-current voltage to the sensor electrode, a second voltage output unit that applies a second alternating-current voltage that has the same frequency and phase as the first alternating-current voltage but a greater amplitude than the first alternating-current voltage to the shield electrode, a detection unit that detects a self-capacitance value for the sensor electrode, an adjustment electrode that is arranged near the sensor electrode, and a voltage setting unit that outputs a third alternating-current voltage that has the same frequency and phase as the first alternating-current voltage but a smaller amplitude than the first alternating-current voltage or a third alternating-current voltage that has the same frequency as the first alternating-current voltage but the opposite phase of the first alternating-current voltage to the adjustment electrode or sets the adjustment electrode to a fixed potential.
Inventors:
YAMADA TOMOKI (JP)
Application Number:
PCT/JP2023/007312
Publication Date:
November 23, 2023
Filing Date:
February 28, 2023
Export Citation:
Assignee:
ALPS ALPINE CO LTD (JP)
International Classes:
G06F3/041; G06F3/044
Domestic Patent References:
| WO2018116706A1 | 2018-06-28 |
Foreign References:
| JP2019125218A | 2019-07-25 | |||
| JP2022066900A | 2022-05-02 |
Attorney, Agent or Firm:
ITOH, Tadashige et al. (JP)
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