| 摘要 |
<p>PURPOSE:To prevent erroneous detection of coordinates from occurring due to an external noise in a coordinate reader which performs coordinate detection by an induced voltage. CONSTITUTION:Scan control means 5 issues an instruction to read the induced voltage to scanning means 4a, 4b by selecting the sense line of a window centering the position of the sense line at which a coordinate indicator 3 is located. Peak detecting means 6 finds the maximum peak voltage vp from a read induced voltage. Mean voltage calculation means 7 finds the means voltage va of the read induced voltage age. External noise decision means 8 decides whether or not the induced voltage is generated by the external noise by differential quantity vs between the peak voltage vp and mean voltage va.</p> |
