| 主权项 |
1. A display layer comprising an electrophoretic fluid sandwiched between a common electrode and a layer of pixel electrodes and having first and second surfaces on opposed sides thereof, the electrophoretic fluid comprising a first type of particles, a second type of particles and a third type of particles, all dispersed in a solvent or solvent mixture, the first, second and third types of particles having respectively first, second and third optical characteristics differing from one another, the first type of particles having a charge of one polarity and the second and third types of particles having charges of the opposite polarity, and the second type of particles having an electric field threshold, such that:
(a) application of an electric field between the common electrode and a pixel electrode, which electric field is greater than the electric field threshold and having the same polarity as the second type of particles, causes an area corresponding to the pixel electrode to display the second optical characteristic at the first surface; (b) application of an electric field between the common electrode and a pixel electrode, which electric field is greater than the electric field threshold and having the same polarity as the first type of particles, causes an area corresponding to the pixel electrode to display the first optical characteristic at the first surface; or (c) once the first optical characteristic is displayed at the first surface, application of an electric field between the common electrode and a pixel electrode, which electric field is the same as, or lower than, the electric field threshold and having the same polarity as the third type of particles, causes an area corresponding to the pixel electrode to display the third optical characteristic at the first surface. |
