LCD PANEL WITH A FUNCTION OF DETECTING PEN POSITIONS

We have developed a new type of LCD panel having a function of detecti ng pen positions for pen entry operation. Until recently, a tablet had to be placed on an LCD panel for the purpose of detecting pen positio ns. In this newly developed type of LCD, however, the combination of m atrix electrodes and driving circuits already co-existing within the L CD panel is used for detecting pen positions by employing time-sharing technique. The present tabletless system has several advantages as fo llows; the weight and thickness of the new LCD panel are kept equal to those of a conventional LCD panel, the deterioration of light transmi ssion and the reflection at a surface are suppressed, and the costly p rocess of combining an LCD panel and a tablet can be eliminated in our system. This paper describes the new LCD system in comparison with a previous tablet-type LCD.