Abstract: A method and apparatus for replacing a fluorescent lighting system with a light emitting diode (LED) system. By connecting the LEDs in accordance with the described embodiment, the fluorescent lamp driving circuit can be reused without modification. The current rating of the LEDs must be equal to or less than the current output of the fluorescent lamp driving circuit. The LED replacement lamp may consist of as few as two LEDs but multiple LEDs may be used as long as the power consumed by the LEDs does not exceed the power rating of the fluorescent lamp driving circuit.

Abstract: An apparatus and method for controlling contrast for a liquid crystal display (“LCD”), especially active-matrix LCDs, while receiving large dynamic range video data to be displayed to the user by the LCD. Contrast settings of the LCD correspond to a single look-up table from a set of different and multiple look-up tables rather than using the contrast setting of the LCD to select different voltage values from a single look-up table. The values of the reference voltages of the LCD are varied so that all shades of gray are available with each contrast selection resulting in a high image quality and a high contrast.

Abstract: Methods of and apparatuses for reducing the solar or infrared loading on display devices. A reflective material is positioned between a radiant energy source and the absorptive material of a display device to reflect wavelengths of radiant energy in the infrared or near-infrared range. The reflective material allows visible radiant energy to be transmitted, while reflecting the infrared radiant energy to reduce the infrared loading on the display device. The present invention reduces the temperature rise of the display device due to infrared loading by reflection rather than absorption of the radiant energy, while preserving the integrity of the visible wavelength range. The reflective material reduces the infrared loading on the display device by up to 50%.

Abstract: A temperature sensor for the liquid crystal portion of a liquid crystal display assembly which includes a thin layer of transparent conductive material which is spread across the viewing area of the display. This layer of transparent conductive material can provide heat to warm up the display when a large voltage is put across it, and can also be used to measure liquid crystal temperature. It is known that the resistance of materials such as indium tin oxide (ITO) changes at a known rate with respect to temperature. By using this transparent layer of material in the stacked elements of a liquid crystal display assembly, an accurate reading of the liquid crystal temperature can be made.

Abstract: A control circuit for providing a common electrode voltage for a liquid crystal display dynamically controls the voltage applied to the common electrode according to various factors that affect the capacitance across the liquid crystal layer. The common electrode control circuit dynamically adjusts the common electrode voltage according to the current maximum and minimum display voltages. In addition, the common electrode control circuit adjusts the common electrode voltage according to the gate-to-source parasitic capacitance, as well as temperature fluctuations. Thus, the control circuit compensates for the most significant factors which may cause he inadvertent accumulation of a charge across the liquid crystal layer.

Abstract: The disclosure is directed to a color liquid crystal display backlight system for daytime and nighttime use. Night vision imaging system retirements are met so that light emissions from the 630 nm to 930 nm range are substantially reduced or eliminated. Separate daytime and nighttime light sources are utilized. The NVIS compatible nighttime source is positioned to be out of sight of a user and produces an appropriately filtered, substantially collimated beam which diffusively reflects from the inside walls and base of the display housing before it illuminates the display surface. Intensities of both daytime and nighttime light sources can be controlled.

Abstract: A remote registration and calibration system for a hybrid video display. The registration and calibration functions are performed by a computer. Display mounted switches are advantageously employed. The computer system samples the state of an array of switches and then performs calibration functions based on the state of the switches.