Pixel unit, method for sensing touch of an object, and display apparatus incorporating the same

A display apparatus, comprising:

• a data line;
• a driving circuit;
• and
• a pixel unit for receiving pixel data transmitted by the driving circuit, comprising:
• a liquid crystal capacitor;
• a fixed capacitor;
• a switch circuit electrically connected to the data line;
• and
• a sensing circuit, electrically connected to the switch circuit, having a variable capacitor electrically connected to the data line via the switch circuit, a capacitance of the variable capacitor being changed in response to a touch of an object, the variable capacitor generating a signal in response to the capacitance thereof;
• wherein the signal comprising an output current generated in response to the touch of the object is transmitted through the data line with the switch circuit being turned on.

A display apparatus for sensing touch of an object, comprising:

• a plurality of data lines;
• a plurality of scan lines;
• and
• a plurality of pixel units, each of the pixel units comprising a liquid crystal capacitor, a fixed capacitor and a variable capacitor electrically connected to a switch circuit and electrically connected to one of the data lines via the switch circuit;
• wherein the variable capacitors of the pixel units generate a plurality of signals in response to the touch of the object, the scan lines are orderly electrically connected to the pixel units to orderly turn on the switch circuits of the pixel units, and the signals comprising output currents generated in response to the touch of the object are transmitted through the data lines by orderly turning on the switch circuits of the pixel units.

A method for sensing touch of an object on a pixel unit, the pixel unit comprising a first switch circuit, a second switch circuit, a fixed capacitor, a liquid crystal capacitor, and a variable capacitor electrically connected to the first switch circuit and the second switch circuit and electrically connected to a data line via the first switch circuit, the method comprising the following steps of:

• turning on the first switch circuit in a first time period and inputting a reference voltage through the data line by the first switch circuit into the variable capacitor;
• generating a signal, by the variable capacitor, in response to a touch of the object according to the reference voltage;
• and
• turning on the second switch circuit in a second time period and transmitting the signal through a readout line by the second switch circuit.

A pixel unit for use in a display apparatus for sensing touch of an object, the display apparatus comprising a data line and a readout line, the pixel unit comprising:

• a first switch circuit electrically connected to the data line;
• a second switch circuit electrically connected to the readout line;
• a fixed capacitor;
• a liquid crystal capacitor;
• and
• a variable capacitor electrically connected to the first switch circuit and the second switch circuit and electrically connected the data line via the first switch circuit;
• wherein the variable capacitor receives a reference voltage from the data line by the first switch circuit in a first time period and generates a signal in response to the touch of the object according to the reference voltage, and the signal is transmitted through the readout line by the second switch circuit in a second time period.

A display apparatus, comprising:

• a data line;
• a driving circuit;
• a readout line;
• and
• a pixel unit for receiving pixel data transmitted by the driving circuit, comprising:
• a first switch circuit electrically connected to the data line;
• a second switch circuit electrically connected to the readout line;
• a fixed capacitor;
• a liquid crystal capacitor;
• and
• a variable capacitor electrically connected to the first switch circuit and the second switch circuit and electrically connected to the data line via the first switch circuit;
• wherein the variable capacitor receives a reference voltage from the data line by the first switch circuit in a first time period and generates a signal in response to a touch of an object according to the reference voltage, and the signal is transmitted through the readout line by the second switch circuit in a second time period.