Timing of fields of video

• US 20020030659A1
• Filed: 02/22/2001
• Published: 03/14/2002
• Est. Priority Date: 02/22/2000
• Status: Active Grant

• Current Assignee: Kopin Corporation
• Original Assignee: Kopin Corporation
• Inventors: Zavracky, Matthew M., Ellertson, David L.
• Granted Patent: US 6,999,057 B2
• Time in Patent Office: Days
• US Class Current: 345/99
• CPC Class Codes: G09G 2320/0204 Compensation of DC component across the pixels in flat panels
• CPC Class Codes: G09G 3/3611 Control of matrices with row and column drivers
• CPC Class Codes: G09G 3/3648 using an active matrix G09G3/367 - G09G3/3696 take precedence

Abstract

An apparatus and method to delay a field of video by one row in a two field frame to reduce DC build-up or stick caused by textual image.

Claims

1. A method of writing a textual image to a liquid crystal display comprising the steps of:

providing a plurality of video frames of video data, each frame as a pair of interlaced video fields;

providing a textual image on at least one row of video data of each of the pair of the interlaced video fields;

determining if a row of textual image on a row of video data of the first video field coincide, lags or leads the row of textual image of the second video field; and

adjusting the timing of one of the video fields based on determination to have the row of textual image on a row of video data of the first video field coincide with the row of textual image of the second video field.

2. The method of claim 1 further comprising the step of:

selecting rows of video data to discard if the video data has an excess number of rows of video for interlace video on the liquid crystal display wherein the same row is selected from each field.

3. A method of selecting portion of video to not write to the display comprising the steps of:

providing video data having an excess number of lines or rows of video for the rows of video for interlace video on the liquid crystal display;

providing the video frames of video data with each frame as a pair of interlaced video fields; and

selecting rows of video data to discard wherein the same row is selected from each field.

4. The method of claim 3 further comprising the step of selecting rows of video data to discard wherein the same row is selected from each field is in the textual areas of the display and non equivalent rows are selected from each field in the non textual areas.