Patent ID: 8593396

Claim:
A method for driving an electro-optic display having a plurality of pixels, each of which is capable of achieving at least two different gray levels, the method comprising: (a) providing a final data buffer arranged to receive data defining a desired final state of each pixel of the display; (b) providing an initial data buffer arranged to store data defining an initial state of each pixel of the display; (c) providing a target data buffer arranged to store data defining a target state of each pixel of the display; (d) determining when the data in the initial and final data buffers differ, and when such a difference is found updating the values in the target data buffer by (i) when the initial and final data buffers contain the same value for a specific pixel, setting the target data buffer to this value; (ii) when the initial data buffer contains a larger value for a specific pixel than the final data buffer, setting the target data buffer to the value of the initial data buffer plus an increment; and (iii) when the initial data buffer contains a smaller value for a specific pixel than the final data buffer, setting the target data buffer to the value of the initial data buffer minus said increment; (e) updating the image on the display using the data in the initial data buffer and the target data buffer as the initial and final states of each pixel respectively; (f) after step (e), copying the data from the target data buffer into the initial data buffer; and (g) repeating steps (d) to (f) until the initial and final data buffers contain the same data.