Liquid crystal display device

A liquid crystal display device, comprising:

• a display substrate including a first transparent substrate and a touch sensing line provided on the first transparent substrate and extending in a first direction;
• an array substrate including a second transparent substrate, a plurality of polygonal pixel apertures on the second transparent substrate, a common electrode provided in each of the plurality of pixel apertures and having a constant potential, a first insulating layer provided under the common electrode, a pixel electrode provided under the first insulating layer in each of the plurality of pixel apertures, a second insulating layer provided under the pixel electrode, a conductive line electrically connected to the common electrode under the second insulating layer and extending in a second direction orthogonal to the first direction to cross the plurality of pixel apertures, a third insulating layer provided under the conductive line, first and second active elements provided under the third insulating layer and electrically connected to the pixel electrode, a first gate line extending in the second direction and establishing electrical linkage with the first active element, a second gate line extending in the second direction and establishing electrical linkage with the second active element, a first source line extending in the first direction in plan view to establish electrical linkage with the first or second active element, and a second source line extending in the first direction in plan view to establish electrical linkage with the second or first active element;
• a liquid crystal layer sandwiched between the display substrate and the array substrate;
• and
• control circuitry configured to supply a negative first video signal to the first source line and a positive second video signal to the second source line, drive the liquid crystal layer by applying a liquid crystal driving voltage across the pixel electrode and the common electrode in synchronization with supply of the negative first video signal and the positive second video signal to display an image, and detect a change in capacitance between the common electrode and the touch sensing line to carry out touch sensing.