Display device supporting a partial driving mode, and method of operating a display device

A method of operating a display device that includes a display panel that includes a first display region, a second display region, and an intermediate display region located between the first display region and the second display region, the method comprising:

• storing first degradation information for a first edge region within the first display region that is adjacent to the intermediate display region;
• storing second degradation information for a second edge region within the second display region that is adjacent to the intermediate display region;
• extracting first edge information for the first edge region from first partial image data for the first display region in a first partial driving mode in which the first display region is driven;
• extracting second edge information for the second edge region from second partial image data for the second display region in a second partial driving mode in which the second display region is driven;
• generating, in the first partial driving mode, first gradation data for the intermediate display region based on the first edge information and the second degradation information;
• generating, in the second partial driving mode, second gradation data for the intermediate display region based on the first degradation information and the second edge information;
• driving, in the first partial driving mode, the first display region and the intermediate display region based on the first partial image data and the first gradation data;
• and
• driving, in the second partial driving mode, the second display region and the intermediate display region based on the second partial image data and the second gradation data.