Display medium driving device, driving method, driving program storage medium, and display device

A storage medium storing a program that causes a computer to execute a process of driving a display medium, the display medium including:

• a display substrate that is light-transmissive;
• a rear substrate that is disposed so as to face the display substrate with a gap therebetween;
• a front electrode that is disposed at the display substrate and is light-transmissive;
• a rear electrode that is disposed at the rear substrate;
• a dispersion medium that is disposed between the front electrode and rear electrodes;
• and
• two or more types of particle groups that are dispersed in the dispersion medium and that include a first particle group and a second particle group having different colors and charge polarities, the first particle group and the second particle group migrating independently of each other due to a first potential difference being imparted between the electrodes for a first time period, the first particle group and the second particle group forming aggregates that are charged positive or negative due to the first potential difference being imparted between the electrodes for a second time period that is shorter than the first time period, and the aggregates migrating due to a second potential difference that is smaller than the first potential difference being imparted,
• the process of driving comprising:
• imparting, between the electrodes, a potential difference that forms the aggregates;
• imparting, between the electrodes, a third potential difference that moves, to the display substrate side, a particle group of which a greater amount of particles is needed for gradation display, in an amount of a difference between an amount of particles of the first particle group and an amount of particles of the second particle group needed for the display;
• when the particle group of which a greater amount of particles is needed for the gradation display has an opposite polarity to the aggregates, imparting, between the electrodes, a fourth potential difference that moves an amount of the aggregates needed for the gradation display to the display substrate side;
• and
• when the particle group of which a greater amount of particles is needed for the gradation display has the same polarity as the aggregates, imparting, between the electrodes, a fifth potential difference that moves an amount of the aggregates not needed for the gradation display to the rear substrate side.

A method of driving a display medium, the display medium including:

• a display substrate that is light-transmissive;
• a rear substrate that is disposed so as to face the display substrate with a gap therebetween;
• a front electrode that is disposed at the display substrate and is light-transmissive;
• a rear electrode that is disposed at the rear substrate;
• a dispersion medium that is disposed between the front electrode and rear electrodes;
• and
• two or more types of particle groups that are dispersed in the dispersion medium and that include a first particle group and a second particle group having different colors and charge polarities, the first particle group and the second particle group migrating independently of each other due to a first potential difference being imparted between the electrodes for a first time period, the first particle group and the second particle group forming aggregates that are charged positive or negative due to the first potential difference being imparted between the electrodes for a second time period that is shorter than the first time period, and the aggregates migrating due to a second potential difference that is smaller than the first potential difference being imparted,
• the method comprising:
• imparting, between the electrodes, a potential difference that forms the aggregates;
• imparting, between the electrodes, a third potential difference that moves, to the display substrate side, a particle group of which a greater amount of particles is needed for gradation display, in an amount of a difference between an amount of particles of the first particle group and an amount of particles of the second particle group needed for the display;
• when the particle group of which a greater amount of particles is needed for the gradation display has an opposite polarity to the aggregates, imparting, between the electrodes, a fourth potential difference that moves an amount of the aggregates needed for the gradation display to the display substrate side;
• and
• when the particle group of which a greater amount of particles is needed for the gradation display has the same polarity as the aggregates, imparting, between the electrodes, a fifth potential difference that moves an amount of the aggregates not needed for the gradation display to the rear substrate side.