Touch-and-display device and sensing system

A sensing system comprising:

• an active stylus, comprising a case and a conductive tip;
• and
• a touch-and-display device having a display area and a non-display area, wherein the touch-and-display device comprises:
• a touch-and-display panel, comprising a plurality of sensing electrodes in the display area, wherein the sensing electrodes are electrically insulated with each other;
• a circuit, disposed in the non-display area and electrically connected to the sensing electrodes through a plurality of sensing lines;
• and
• a peripheral electrode, disposed in the non-display area,
• wherein in a display period, the circuit applies a common voltage to the sensing electrodes through the sensing lines,
• wherein in a touch sensing period, the circuit transmits a touch sensing signal to the sensing electrodes through the sensing lines, and determines whether each of the sensing electrodes is touched based on capacitance of the sensing electrodes,
• wherein in a stylus sensing period, the circuit transmits an uplink signal to the sensing electrodes and the peripheral electrode, and receives a downlink signal from the active stylus through the sensing electrodes, and determines a stylus location corresponding to the active stylus according to the downlink signal.