A color display device in which each pixel can display four high-quality color states. More specifically, an electrophoretic fluid is provided which comprises four types of particles, dispersed in a solvent or solvent mixture, wherein each type of particle has a different charge profile (polarity and magnitude) and a different optical characteristic. When driven with a two-step process, the particles of lower charge magnitude can be driven to the viewing surface while the particles with higher charge magnitude are not viewable at the viewing surface.

A method for secure updating of a static state display, the method comprising: sending (102) data from an updating device (400) to the static state display (300), wherein the data comprises a security key and update data pertaining to an update (302) to be displayed by the static state display (300); authenticating (104) the data sent by the updating device (400) at the static state display by comparing the security key with one or more reference security keys stored in a database accessible by the static state display (300); and upon successful authentication updating (106) the static state display (400) with the update (302). A system (200) comprising a static state display (300) and an updating device (400) is further provided.

There are provided display controllers and driving methods related to those described in US Published Patent Application No. 2013/0194250. These include (a) a display controller having an update buffer, means for removing from the update buffer pixels not requiring updating, and means to ensure that pixels having certain special states are not removed from the update buffer; (b) a method of driving a bistable display wherein, in a pixel undergoing a white-to-white transition and lying adjacent another pixel undergoing a visible transition, there is applied to the pixel one or more balanced pulse pairs and at least one top-off pulse; (c) a method of driving a bistable display by overlaying a non-rectangular item over a pre-existing image content and then removing the item, where only pixels in the region of the item perform transitions (including self-transitions); and (d) a method of driving a bistable display in which a proportion of background pixels not undergoing an optical change are subjected to a refresh pulse to correct optical state drift.

A color display device in which each pixel can display four high-quality color states. More specifically, an electrophoretic fluid is provided which comprises four types of particles, dispersed in a solvent or solvent mixture, wherein each type of particle has a different charge profile (polarity and magnitude) and a different optical characteristic. When driven with a two-step process, the particles of lower charge magnitude can be driven to the viewing surface while the particles with higher charge magnitude are not viewable at the viewing surface.

The present invention provides a solution for a highlight or multicolor display device, in which each display cell can display high quality color states. More specifically, an electrophoretic fluid is provided which comprises three types of pigment particles, having different levels of size, threshold voltage or charge intensity.

The present invention provides driving methods for a color display device in which each pixel can display four high-quality color states. More specifically, an electrophoretic fluid is provided which comprises four types of particles, dispersed in a solvent or solvent mixture.

The present invention provides a solution for a highlight or multicolor display device, in which each display cell can display high quality color states. More specifically, an electrophoretic fluid is provided which comprises three types of pigment particles, having different levels of size, threshold voltage or charge intensity.

A method of fabricating a display comprising a plurality of autonomous pixels is described. Each autonomous pixel comprises a display element and a control element. The control element is configured to sense an external stimulus and to generate, entirely within the autonomous pixel, a control signal to drive the display element based, at least in part, on the magnitude of the sensed external stimulus.

A display device which includes an electronic paper display additionally comprises power harvesting hardware and display update hardware which is configured to control the updating of the electronic paper display based on a sensed power harvesting level which may, in various embodiments, be a current incoming power level as generated by the power harvesting hardware or a stored power level in a power storage device within the display device.

The present invention provides driving methods for a color display device in which each pixel can display four high-quality color states. More specifically, an electrophoretic fluid is provided which comprises four types of particles, dispersed in a solvent or solvent mixture.