Methods for operating electro-optic displays
A method of operating an electro-optic display in which an image is scrolled across the display, and in which a clearing bar is provided between two portions of the image being scrolled, the clearing bar scrolling across in display in synchronization with said two portions of the image, the writing of the clearing bar being effected such that every pixel over which the clearing bar passes is rewritten.
1. A method of operating an electro-optic display in which an image is formed on the display, and in which a clearing bar is provided which travels across the image on the display, such that every pixel over which the clearing bar passes is rewritten, the clearing bar configured to reduce ghosting effects and being located in pixels that are initially on screen or in pixels that are in the software memory but not on the screen, and wherein the clearing bar is patterned and uses a color different from a background color, or two or more clearing bars of different colors or patterns are used.
2. The method of claim 1 , wherein the clearing bar has a form of a frame around an image, the frame being smaller than a display size or larger than a display size.
3. The method of claim 1 , wherein a minimum number of pixels in the clearing bar or a height of the clearing bar in a direction of scrolling is at least equal to the number of pixels by which the image moves at each scrolling image update and the clearing bar height varies dynamically.
4. The method of claim 1 , wherein the clearing bar uses the same gray tones as a striped background and is out of phase with the background by one block.
5. The method of claim 1 , wherein the clearing bar has a form of a series of discrete points across the display strategically placed such that when the discrete points are scrolled across the display the discrete points force every pixel to switch.
6. The method of claim 5 , wherein the clearing bar is in a form of a number of spread out points, the height of the clearing bar accounts for the spacing between the points.
7. The method of claim 1 , wherein a drive scheme having the same or shorter length than that used for the remaining part of the display is used for the clearing bar.
8. The method of claim 1 , wherein when a drive scheme of the clearing bar is longer that used for the remaining part of the display, not all the pixels in the clearing bar will switch at once but rather a wide subsection of the pixels will switch while there are non-switching pixels and regularly switching pixels moving around the clearing bar.