Display device and control method thereof

A display device, comprising:

• a casing having an opening;
• a display unit configured to be inserted into and withdrawn from the casing through the opening;
• a display mover connected to the display unit and configured to move the display unit;
• a sensor configured to measure a distance between a lower portion of the casing and a lower end of the display unit, the distance being in a direction parallel to the direction of insertion and withdrawal of the display unit;
• and
• a controller configured to transfer a signal to the display mover and the display unit,
• wherein the display unit moves according to a mode so that an area exposed to an outside of the casing differs according to the mode, the mode being determined based on the distance measured by the sensor,
• wherein:
• the display unit includes a display driver configured to control a plurality of horizontal pixel lines included in a display,
• the controller transfers a screen control signal to the display driver, and
• the display driver controls image output of the horizontal pixel lines based on the screen control signal,
• wherein:
• the screen control signal includes an active period and an inactive period,
• the display driver applies a voltage to a horizontal pixel line based on the screen control signal of an active state,
• a starting point of the active period differs according to the mode, and
• a duration of the active period of the screen control signal differs based on the mode and is calculated based on a product of a scan rate for each line of pixels and a number of lines of pixels corresponding to the mode, and
• wherein:
• the active period or the inactive period of the screen control signal is based on a synchronization signal, and
• the synchronization signal is a signal indicating an order of image data, such that the screen control signal is activated upon receiving the synchronization signal indicating first image data and deactivated upon receiving the synchronization signal indicating last image data.