BACKLIGHT ADJUSTMENT SYSTEM

• US 20160037606A1
• Filed: 10/15/2015
• Published: 02/04/2016
• Est. Priority Date: 05/21/2008
• Status: Active Grant

• Current Assignee: Manufacturing Resources International, Inc.
• Original Assignee: Manufacturing Resources International, Inc.
• Inventors: DUNN, William, Schuch, John, Williams, David
• Granted Patent: US 9,867,253 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G09G 2320/041 Temperature compensation
• CPC Class Codes: G09G 2330/021 Power management, e.g. power saving
• CPC Class Codes: G09G 3/36 using liquid crystals
• CPC Class Codes: H05B 45/12 using optical feedback
• CPC Class Codes: H05B 45/14 using electrical feedback from LEDs or from LED modules
• CPC Class Codes: H05B 45/18 using temperature feedback
• CPC Class Codes: H05B 47/11 by determining the brightness or colour temperature of ambient light
• CPC Class Codes: Y02B 20/40 Control techniques providing energy savings, e.g. smart controller or presence detection

Abstract

A preferred embodiment relates to controlling the amount of backlight power in an electronic display to account for the temperature in the backlight cavity. Another embodiment relates to a system for controlling the amount of backlight based on both the temperature of the backlight and the amount of ambient light.

Claims

1. A system for lighting an electronic display, the system comprising:

an electronic display with a viewing surface and a backlight;

a power source operatively connected to said backlight such that as power to said backlight is increased the amount of illumination output from the backlight is increased, and as power to said backlight is decreased the amount of illumination output from said backlight is decreased;

a sensor which measures ambient light;

a sensor which measures light emitted by said backlight; and

software in operative communication with said sensors and said power source; and

wherein the software is configured to access a database indicating a range of a preferred amount of backlight illumination for a given amount of ambient light, and

automatically increase the power of said power source when the amount of backlight illumination falls below said preferred illumination range for the sensed amount of ambient light at a given time, and

decrease the power of said power source when the amount of backlight illumination is above said preferred illumination range for the sensed amount of ambient light at a given time.

2. The system of claim 1 further comprising a power measurement device operatively connected between said power source and said backlight and providing power data to said software.

3. The system of claim 1 wherein said software is driven by an eeprom.

4. The system of claim 1, wherein the backlight comprises:

a mounting element;

a reflective element covering one surface of the mounting element; and

one or more illuminating devices fixedly attached to the mounting element on the surface containing the reflective element.

5. The system of claim 4, wherein said mounting element comprises a printed circuit board.

6. The system of claim 4, wherein said one or more illuminating devices comprise any one of the following:

LED'"'"'s and fluorescent lights.

7. The system of claim 1 wherein said electronic display is a liquid crystal display.

8. A method for lighting an electronic display device having a viewing surface and backlight, the steps comprising:

setting a maximum operating temperature for said backlight;

storing a range of a preferred amount of backlight illumination for a given amount of ambient light;

measuring a temperature of the backlight;

measuring an amount of ambient light;

calculating a light ratio; and

dimming the backlight slightly when the temperature of the backlight exceeds the maximum operating temperature or the amount of backlight illumination is too high for the amount of ambient light.

9. The method of claim 8 further comprising the steps of:

measuring an amount of light generated by the backlight; and

increasing power to the backlight when the amount of light generated by the backlight is too low for the amount of ambient light.

10. A method for controlling the backlight in an electronic display device, the steps comprising:

providing an electronic display device having a viewing surface and a backlight;

providing a power source which sends power to the backlight;

providing a sensor which measures an operating temperature of said display device;

providing software which is operatively in communication with said power source and said sensor;

storing a preferred operating temperature range for said display device; and

providing electrical signals to the power source through said software to decrease the power to the backlight when said operating temperature exceeds said preferred operating temperature range until the operating temperature returns to within the preferred operating temperature range.

11. The method of claim 10 further comprising the steps of:

measuring the power sent from the power source to the backlight;

comparing the power measurement to a desired amount of power for the power source; and

modifying the amount of power sent from the power source if said power measurement does not match the desired amount of power for the power source.

12. The method of claim 10 further comprising the steps of:

measuring the amount of ambient light;

measuring the amount of light generated by the backlight;

storing a preferred amount of backlight illumination for a given amount of ambient light;

increasing the power of said power source when the amount of backlight illumination is too low for the amount of ambient light; and

decreasing the power of said power source when the amount of backlight illumination is too high for a given amount of ambient light.