A pointing device comprises a substrate having a fixed pivoting hole area defined by a hole through a conductive surface that is coated with electrically conductive material and comprises four segments of patterned resistive materials. Each segment includes a plurality of spaced thick film pieces that...http://www.google.com.tw/patents/US6236034?utm_source=gb-gplus-share專利 US6236034 - Pointing device having segment resistor subtrate
