US 7,746,431 B2 · Dual mode display

Abstract

A dual mode Liquid Crystal Display (LCD) capable of functioning in a dual mode, a monochrome reflective mode and a color transmissive mode. The present invention provides an LCD with color filters only over the transmissive part of a pixel, enabling readability in the ambient light. Yet another aspect of the present invention is the elimination of the black matrix mask used typically in color filter creation. Additionally, the present invention provides diagonal pixels to improve the resolution of the LCD in the color transmissive mode. Further, an aspect of the present invention enables the light to switch between two colors, while a third color (typically green) is always on, thereby, decreasing the required frame rate of the LCD, when used in the hybrid field sequential approach. Yet another aspect of the present invention is to create colors from the backlight, eliminating the need for color filters. Yet another aspect of the present invention is use of color filters over only the green pixels, eliminating the need for using additional masks for making the color filter array.

Claims20

Dependent claims

A dual mode Liquid Crystal display, comprising:

a. a light source for illuminating the dual mode display;
b. a first polarizer for aligning the plane of polarization of light from the light source to a first plane
c. a second polarizer for aligning the plane of polarization of the light from the light source to a pre-defined second plane;
d. a first substrate and a second substrate, the first substrate and the second substrate being interposed between the first polarizer and the second polarizer;
and
e. a plurality of pixels, each of the plurality of pixels being positioned at the first substrate, each of the plurality of pixels comprising a reflective part and a transmissive part, wherein the reflective part has no color filter, at least part of the transmissive part comprises one or more color-filters;
wherein each of the one or more color filters imparts one of three different colors, and transmissive parts of pixels imparted with a first color of the three different colors are arranged in a first diagonal stripe, transmissive parts of pixels imparted with a second color of the three different colors are arranged in a second diagonal stripe, and transmissive parts of pixels imparted with a third color of the three different colors are arranged in a third diagonal stripe.

4 more elements

Dependencies are inferred from the claim text.

Dual mode display

Life of this patent

Dual mode display

Life of this patent

Abstract

Claims20