US 6,144,359 A · Liquid crystal displays utilizing polymer dispersed liquid crystal devices for enhanced performance and reduced power

Abstract

Disclosed is an avionics display device for use in the cockpit of an aircraft. The display device includes a liquid crystal display adapted for using a source of light to display information to a viewer and a backlight adapted to controllably provide a portion of the source of light for use by the liquid crystal display in displaying the information. A polymer dispersed liquid crystal (PDLC) device is positioned between the liquid crystal display and the backlight. An ambient light sensor adapted to sense a level of ambient light in the cockpit of the aircraft provides a sensor output indicative of the sensed ambient light level. Luminance control circuitry coupled to the ambient light sensor, to the backlight and to the PDLC device, receives the sensor output and generates as a function of the sensed ambient light level control signals for controlling the intensity of the light provided by the backlight and the transmissivity of the PDLC device.

Claims18

Dependent claims

An avionics display device for use in the cockpit of an aircraft, the display device comprising:

a liquid crystal display in a transflective mode adapted for using a source of light to display information to a viewer;
a backlight adapted to controllably provide at least a portion of the source of light for use by the liquid crystal display in displaying the information;
a polymer dispersed liquid crystal (PDLC) device positioned between the liquid crystal display and the backlight;
an ambient light sensor adapted to sense a level of ambient light in the cockpit of the aircraft and to provide a sensor output indicative of the sensed ambient light level;
and
luminance control circuitry coupled to the ambient light sensor, to the backlight and to the PDLC device, the luminance control circuitry receiving the sensor output and generating as a function of the sensed ambient light level control signals for controlling an intensity of the light provided by the backlight and for controlling the transmissivity of the PDLC device.

3 more elements

An avionics display device for use in the cockpit of an aircraft, the display device comprising:

transmissive mode liquid crystal display means for displaying information to a viewer;
backlight means for controllably providing a first source of light for use by the transmissive mode liquid crystal display means in displaying the information;
and
polymer dispersed liquid crystal (PDLC) device means positioned between the transmissive mode liquid crystal display means and the backlight means for controllably transmitting toward the transmissive mode liquid crystal display means a minority of the first source of light from the backlight means during night mode operations;
and
ambient light sensing means for sensing a level of ambient light in the cockpit of the aircraft and providing a sensor output indicative of the sensed ambient light level;
and
luminance control means coupled to the ambient light sensing means, to the backlight means and to the PDLC device means, for receiving the sensor output and automatically generating as a function of the sensed ambient light level control signals for controlling an intensity of the first source of light provided by the backlight means and for controlling a transmissivity of the PDLC device means.

5 more elements

Dependencies are inferred from the claim text.

Liquid crystal displays utilizing polymer dispersed liquid crystal devices for enhanced performance and reduced power

Life of this patent

Liquid crystal displays utilizing polymer dispersed liquid crystal devices for enhanced performance and reduced power

Life of this patent

Abstract

Claims18