Display device and method of displaying image

A display device, comprising:

• a display panel having a passive matrix structure having a plurality of cathode rays, which are disposed in parallel, a plurality of anode rays which are disposed in parallel and are perpendicular to the cathode rays and a plurality of light emitting diodes disposed at each intersection of the cathode and anode rays, the display panel producing luminescence by the drive current flowed from each anode ray to a selected cathode ray via the light emitting diodes;
• a memory storing image data inputted, which includes a plurality of display data, each of which indicates one-line image data of the image data, and outputting one of the display data to be displayed at the display panel, the display data corresponding to one of the cathode rays;
• a column driver supplying drive current or voltage having a stipulated value or the less from power sources, which are commonly controlled by a control signal, to one or more anode rays, which are intended to be activated in response to the display data outputted from the memory;
• a row driver connecting one of the cathode rays, which is designated by the display data, to a power supply voltage;
• and
• a controller detecting a black line, in which all light emitting diodes in one line are non-luminescence, counting a number of times (S) that the display data indicating the black line is sent to the display panel in serial, halting a scanning operation to the display data indicating the black line, applying the time period for halting the scanning operation to another time period for displaying display data, which are next to the display data indicating the black line and which is not the display data indicating the black line, whereby the another time period for displaying display data is set to “S+1” times longer than a stipulated time period, and sending the control signal to the column driver, which controls the column driver to set the drive current or voltage applied from the power source to a “1/(S+1)” of the stipulated value for the “S+1” time period.