Methods of operating display devices and apparatus for performing the methods.

摘要

A method and means for creating the display illusion of 'roughness' or 'texture' in patterns suitable for an electrochromic display surface by assigning different colour values to pels (picture elements) in adjacent positions and then replicating the patterns automatically using the recurrent and sequential accessing of a concordance table. The real colour of each pel of a textured pattern is a joint function of a colour number stored in a refresh buffer driving the display surface for any given display matrix array pel position and the value of a predetermined subset of address bits which describe that pel position. The use of preselected pel position address bits for regulating texture is shown as applied to video lookup tables and refresh buffers as a single level control and additionally to two or more video lookup tables for achieving a pattern hierarchy.

In the drawing the colour number is obtained from refresher buffer 9 and applied, together with the most significant bits of the address applied to the buffer, to i the store 19 containing the required colour values. The colour values are converted to analogue signals and used I to drive the electrochromic display device 29.