Display controller system

• US 9,390,661 B2
• Filed: 03/14/2013
• Issued: 07/12/2016
• Est. Priority Date: 09/15/2009
• Status: Active Grant

• Current Assignee: E Ink Holdings Incorporated
• Original Assignee: E Ink California, LLC (E Ink Corporation)
• Inventors: Chiu, Wen-Pin, Lin, Craig
• Primary Examiner(s): BEUTEL, WILLIAM A
• Application Number:
  US13/828,370
• Publication Number:
  US 20130222404A1
• Time in Patent Office: 1,216 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: G06T 1/60 Memory management
• CPC Class Codes: G09G 2340/16 Determination of a pixel data signal depending on the signal applied in the previous frame
• CPC Class Codes: G09G 3/344 based on particles moving in a fluid or in a gas, e.g. electrophoretic devices electrophoretic devices per se G02F1/167
• CPC Class Codes: G09G 5/399 using two or more bit-mapped memories, the operations of which are switched in time, e.g. ping-pong buffers

Abstract

A display controller system with a memory controller and buffers is described.

The system enables transferring data from the main memory of the CPU to the image memory without interfering the image updating. As a result, the present invention may allow continuously updating the display image and continuously writing new image data from CPU to the image memory which improves overall system performance.

Claims

1. A method of transferring image data for a display device assembly, which comprises

a CPU memory;

a display controller comprising two buffers, a memory controller and a look-up table;

an image memory; and

a display device;

wherein new image data are transmitted from the CPU memory to the buffers as determined by the memory controller,

which method comprises;

(A) (i) accessing current and next image data from the image memory and comparing the two images,

(ii) finding appropriate driving wave forms, one for each of the pixels in a given line, from the look-up table,

(iii) forwarding to the display device voltage data of the appropriate driving waveforms to be applied to each of the pixels in the given line;

(B) during an idle time transferring image data from one buffer of the two buffers which is full to the image memory and simultaneously transferring image data from the CPU memory to another buffer of the two buffers, wherein the idle time is after voltages for a line of pixels have been sent to the display device and before waveforms of a next line of pixels are processed, wherein both steps A and B are completed within a line updating time period, and

(C) repeating steps A and B in an alternating manner and step B is present only when one of the buffers is full.

2. The method of claim 1, wherein step C is carried out in more than one frame period.

3. The method of claim 1, wherein step C is carried out in more than one waveform driving period.

4. The method of claim 1, wherein said display device is an electrophoretic display.

5. The method of claim 1, wherein said line updating time period is calculated from a frame period divided by the number of lines of pixels.

6. The method of claim 1, wherein the two buffers operate as ping-pong buffers.

7. The method of claim 1, wherein said image memory has at least three spaces.

8. The method of claim 1, wherein a size of the buffers is about 0.001% to about 10% of a size of data of a single image being displayed by the display device.