Method for driving a cooling fan within an electronic display

• US 8,700,226 B2
• Filed: 05/25/2010
• Issued: 04/15/2014
• Est. Priority Date: 02/24/2009
• Status: Active Grant

• Current Assignee: Manufacturing Resources International, Inc.
• Original Assignee: Manufacturing Resources International, Inc.
• Inventors: Schuch, John, De Laet, Rick
• Primary Examiner(s): PATEL, RAMESH B
• Application Number:
  US12/787,152
• Publication Number:
  US 20110127026A1
• Time in Patent Office: 1,421 Days
• Field of Search: 700299-300, 349/161, 361/600, 361/679.04, 361/679.06, 361/679.29, 713/320.34
• US Class Current: 700/300
• CPC Class Codes: G02F 1/13312 Circuits comprising photodetectors for purposes other than feedback
• CPC Class Codes: G02F 1/133382 Heating or cooling of liquid crystal cells other than for activation, e.g. circuits or arrangements for temperature control, stabilisation or uniform distribution over the cell
• CPC Class Codes: G02F 1/133385 with cooling means, e.g. fans
• CPC Class Codes: G05D 23/1917 using digital means
• CPC Class Codes: G09G 2320/041 Temperature compensation
• CPC Class Codes: G09G 2360/144 the light being ambient light
• CPC Class Codes: H10K 50/87 Arrangements for heating or cooling
• CPC Class Codes: H10K 59/8794 Arrangements for heating and cooling

Abstract

A system and method for controlling the cooling fan within an electronic display based on the amount of ambient light present. An ambient light sensor is used to measure the amount of ambient light which is contacting the display. To anticipate a temperature rise and lower the thermal inertia of the display, the fan speed is increased when high ambient light levels are measured at the exterior of the display. The ambient light sensor data may be used to apply a temperature correction factor to a temperature sensor within the display. Alternatively, the ambient light sensor data may be used to apply a fan speed correction factor to a desired fan speed (calculated based on a temperature sensor within the display). Multiple systems or methods can be used simultaneously within the display to cool several components which may heat and cool at different rates relative to one another. The various systems can have similar or different logic depending on the amount of cooling needed and the manner in which the cooled-components produce/absorb heat.

Claims

1. A method for driving a cooling fan within an electronic display, the method comprising the steps of:

measuring the ambient light contacting the display;

measuring the temperature within the display;

selecting a temperature correction factor based on the ambient light measurement;

applying the temperature correction factor to the temperature measurement to produce corrected temperature data;

selecting a fan speed based on the corrected temperature data; and

driving the cooling fan at the selected fan speed.

2. The method of claim 1 wherein:

the temperature measurement is performed near a power module which powers the electronic display.

3. The method of claim 1 wherein:

the temperature measurement is performed near a backlight component of the electronic display.

4. A method for driving the cooling fan of an electronic display, the method comprising the steps of:

measuring the temperature within the display;

selecting a desired fan speed based on the temperature measurement;

measuring the ambient light contacting the display;

selecting a fan speed correction factor based on the ambient light measurement;

applying the fan speed correction factor to the desired fan speed to produce a corrected fan speed; and

driving the cooling fan at the corrected fan speed.

5. The method of claim 4 wherein:

the temperature measurement is performed near a power module which powers the electronic display.

6. The method of claim 4 wherein:

the temperature measurement is performed near a backlight component of the electronic display.