| 摘要 |
A capacitive position sensor for detecting the position of an object, typically an operator's finger (105), relative to a resistive sensing element (207), wherein the sensing element comprises a sensing path that has terminals (201, 202, 203) connected along it that subdivide the sensing path into multiple sections (204, 205, 206). Each terminal (201, 202, 203) is coupled to its own sensing channel (301-305), each of which generates a signal that is sensitive to the capacitance between its terminal and a system ground (107). The signals are fed to a processor for analysis. The processor determines over which section the object is positioned by comparing the signals from the sensing channels, and determines the position of the object within that section by comparing the signals from the terminals spanning that section. In this way, the sensing path can be formed in a closed loop, such as a circle for a scroll dial, in which the operator's finger position and movement can be uniquely determined in a straightforward manner. |
