Liquid crystal lens and display device

A liquid crystal lens, comprising:

• a first electrode electrically connected with a voltage source;
• a second electrode arranged opposite to the first electrode;
• a liquid crystal layer located between the first electrode and the second electrode;
• a third electrode, located at a side of the first electrode away from the liquid crystal layer;
• and
• a switch element electrically connected with the voltage source,
• wherein the switch element has a first terminal electrically connected to the first electrode via the voltage source, a second terminal electrically connected with the second electrode, and a third terminal electrically connected with the third electrode,
• wherein the switch element is configured to:
• in a 3D display mode, connect the first terminal with the second terminal so as to apply voltages to the first electrode and the second electrode to generate an electric field, such that liquid crystal molecules in the liquid crystal layer are deflected to a first state and form a plurality of lens units, and
• when switching from the 3D display mode to a 2D display mode, connect the first terminal with the third terminal so as to apply voltages to the first electrode and the third electrode to generate an electric field, such that the liquid crystal molecules in the liquid crystal layer are deflected to a second state and form no lens unit,
• wherein the first electrode comprises a plurality of first strip sub-electrodes arranged in parallel with each other in a first direction, the second electrode comprises a plurality of second strip sub-electrodes arranged in parallel with each other in the first direction, and a width of each of the first strip sub-electrodes in the first direction is smaller than a width of each of the second strip sub-electrodes in the first direction.