| 摘要 |
PROBLEM TO BE SOLVED: To provide an input device of electrostatic type for detecting that foreign matter such as coins or water droplets, etc. have been removed.SOLUTION: An input device 100 includes: an input operation unit 1 having a plurality of capacitance detection unit 1a, and on which an operation medium 60 performs proximity operation; a capacitance measurement unit for measuring an electrostatic capacitance value for each capacitance detection unit, and outputting the measured electrostatic capacitance value as a measurement signal (ADi); and a control unit for acquiring the measurement signal (ADi) in association with the capacitance detection unit, and updating a base value (BASEi) using the measurement signal (ADi), as well as finding a capacitance change value (ΔCi) from a difference between the measurement signal (ADi) and the base value (BASEi), and determining whether or not the capacitance change value (ΔCi) has exceeded a first threshold (THt) and detecting the presence of operation. The control unit determines that foreign matter has been removed by comparing an aggregate value (ΣΔC) that is the sum total of capacitance change values (ΔCi) assuming negative values and a second threshold (THw).SELECTED DRAWING: Figure 2 |
