Pen detection system

A pen detection system that detects a pen signal transmitted from a pen to detect a position of the pen, the pen detection system comprising:

• a sensor pattern in which a column electrode group including first and second partial column electrode groups and a row electrode group including first and second partial row electrode groups are placed on top of each other in a two-dimensional region;
• a first integrated circuit,
• that is connected to the first partial column electrode group to acquire a first column level distribution indicating a level distribution of the pen signal in the first partial column electrode group;
• and
• that is connected to the first partial row electrode group to acquire a first row level distribution indicating a level distribution of the pen signal in the first partial row electrode group;
• and
• a second integrated circuit,
• that is connected to the second partial column electrode group to acquire a second column level distribution indicating a level distribution of the pen signal in the second partial column electrode group;
• and
• that is connected to the second partial row electrode group to acquire a second row level distribution indicating a level distribution of the pen signal in the second partial row electrode group, wherein
• the pen detection system,
• derives a column direction position of the pen in the two-dimensional region, based on the first and second column level distributions;
• and
• derives a row direction position of the pen in the two-dimensional region, based on the first and second row level distributions,
• wherein,
• a predetermined number of at least 4 boundary column electrodes positioned near a boundary between the first partial column electrode group and the second partial column electrode group among a plurality of column electrodes included in the column electrode group are connected to both of the first and second integrated circuits, and
• one of the first or second integrated circuits sets a terminal connected to the boundary column electrode to high impedance when the other of the first or second integrated circuits detects a level of the pen signal in the boundary column electrode.