Indicatory one somatotype digitizing tablet

摘要

PURPOSE: To improve the duty ratio of a display and correctly detect the tip coordinates of a detection pen. ;CONSTITUTION: A multiplexer 13, while selecting the side of an input terminal B in a display period, selects the side of an input terminal A in a coordinate detection period. A lower common driving circuit 2L, while operating in the display period in parallel to an upper common driving circuit 2U according to shift data sent out of the multiplexer 13, operates in the coordinate detection period in series with the upper common driving circuit 2U. An upper segment driving circuit 3U and a lower segment driving circuit 3L operate at the same time to drive upper segment electrodes XU and lower segment electrodes XL at the same time in the same direction. Thus, images are displayed on the upper half part 1wU and lower half part 1wL on a display panel 1w in the display period to improve the duty ratio of the display. In the coordinate detection period, on the other hand, the upper half part 1wU and lower half part 1wL of the display panel 1w are scanned in series to correctly detect the (y) coordinates of two points P₁ and P₂.;COPYRIGHT: (C)1993,JPO&Japio