US 9,541,794 B2 · High dynamic range liquid crystal display

Abstract

A display may have a first stage such as a color liquid crystal display stage and a second stage such as a monochromatic liquid crystal display stage that are coupled in tandem so that light from a backlight passes through both stages. The dynamic range of the display may be enhanced by using the second stage to perform local dimming operations. The pixel pitch of the second stage may be greater than the pixel pitch of the first stage to ease alignment tolerances and reduce image processing complexity. The color stage and monochromatic stages may share a polarizer. A color filter in the color stage may have an array of red, green, and blue elements or an array of white, red, green, and blue elements. The color stage may be a fringe field display and the monochrome stage may be an in-plane switching display or a twisted nematic stage.

Claims10

Dependent claims

A display, comprising:

a color stage having pixels with a first pitch;
a monochromatic stage having pixels with a second pitch that is greater than the first pitch;
backlight structures that include a light source, that include a quantum dot structure that receives light from the light source, and that include a light guide plate that receives light from the quantum dot structure and provides backlight, wherein the color stage and monochromatic stage are coupled in tandem so that the backlight passes through both the color stage and the monochromatic stage;
and
display circuitry that receives red-green-blue image data, converts the red-green-blue image data into white-red-green-blue image data, computes a brightness setting to be supplied to a backlight controller based on the red-green-blue image data, and splits the white-red-green-blue image data into a first channel supplied to the color stage and a second channel supplied to the monochromatic stage.

2 more elements

A display, comprising:

a color stage having a first layer of liquid crystal material and having pixels with a first pixel pitch;
a monochromatic stage having a second layer of liquid crystal material and having pixels with a second pixel pitch that is greater than the first pixel pitch;
a backlight that produces light using a light source, wherein the color stage and monochromatic stage are coupled in tandem so that the light from the backlight passes through both the color stage and the monochromatic stage, wherein the color stage has a first polarizer, and wherein the monochromatic stage has a second polarizer;
a common polarizer that is shared by the color stage and the monochromatic stage;
a white-red-green-blue converter that is configured to receive red-green-blue image data and convert the red-green-blue image data into white-red-green-blue image data, wherein the white-red-green-blue converter is configured to compute a brightness setting for the backlight based on the red-green-blue image data;
a backlight controller configured to receive the brightness setting from the white-red-green-blue converter and adjust the output of the light source in the backlight based on the brightness setting;
a color space converter configured to convert the white-red-green-blue image data into a color space;
and
an image splitter configured to split the white-red-green-blue image data into a first channel supplied to the color stage and a second channel supplied to the monochromatic stage.

6 more elements

Dependencies are inferred from the claim text.

High dynamic range liquid crystal display

Life of this patent

High dynamic range liquid crystal display

Life of this patent

Abstract

Claims10