Adjusting subpixel intensity values based upon luminance characteristics of the subpixels in liquid crystal displays

Abstract

The viewing angle characteristics of a liquid crystal display (LCD) (112) are improved by reducing the number of sub-pixels in an image having half-tone luminance. In a preferred embodiment, the entries of the first table relate sub-pixel luminance values ​​and sub-pixel luminance values ​​in at least one viewing angle direction in the LCD. The second table associates target luminance values ​​with luminance values ​​above and below the target value. The luminance values ​​of adjacent sub-pixels are corrected according to the second table, thereby reducing the number of sub-pixels with halftone luminance.

Description

technical field [0001] The present invention relates to liquid crystal displays (LCDs), and more particularly to improvements in viewing angles of liquid crystal displays. Background technique [0002] Most modern liquid crystal display panels suffer from poor viewing angle characteristics (color shift and level inversion as a function of viewing angle) over the range of subpixel luminance values ​​between light and dark states. Among the various liquid crystal modes used in these displays, the most commonly used is the twisted nematic mode (TN mode), which has worse viewing angle characteristics than other modes. Generally, a normally white mode is adopted, the fully bright state corresponds to the applied low voltage, and the fully dark state corresponds to the applied high voltage. The elements of a displayed image are usually called pixels, and each pixel is usually composed of three sub-pixels, namely red, green, and blue sub-pixels. A typical LCD has striped pixels, ...

AI Technical Summary

Problems solved by technology

The main disadvantage of this approach is that it requires a special sub-pixel structure in the array on the glass plate

A disadvantage of this technology is that it requires a special on-glass structure, the double-row structure

Another problem is that a constant difference between pixel column voltages does not result in light emission, which is consistent with both columns having the same pixel voltage for all levels

Also, many of the above approaches generally do not scale to high-density pixel arrays since special pixel structures require a large portion of the total usable area for improved viewing angles

The remaining area limits the achievable aperture area in the design as the pixel area shrinks

Complex pixel structures can also make it difficult to achieve high yield

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