Method and apparatus for fast heating cold cathode fluorescent lamps
AssigneeVisteon Global Technologies, Inc.
InventorPaul F. L. Weindorf
Life of this patent
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Abstract
A method and apparatus are provided for fast heating cold cathode fluorescent lamps (CCFL). Specifically, values corresponding to the actual luminance of a CCFL are compared to a desired luminance level and, if it is determined that the CCFL is operating under start-up conditions, a boost power supply is applied to the CCFL until either the CCFL outputs the desired luminance level, or a timer determines that start-up conditions no longer exist.
Claims24
A system for controlling luminance output from a backlight usable in combination with an illuminated vehicular display, the system comprising:
- a sensor configured to receive actual signals indicating an actual luminance level of said backlight;
- a first integrator configured to compare said actual luminance signals to predetermined desired signals and output the integration of the difference thereof;
- and
- a second integrator configured to receive said output of said first integrator and supply a boost power level to said backlight when 1) it is determined that said backlight is in a start-up period and 2) said actual luminance level has been less than said desired luminance level for a predetermined amount of time.
A method for dynamically controlling luminance output from a backlight of a vehicular display comprising, said backlight providing illumination to said display, the method comprising:
- (A) inputting a first power level to said backlight from a first power source, wherein said first power level varies over a range including a predetermined control range;
- (B) sensing a first signal corresponding to an actual luminance level of said backlight;
- (C) comparing said first signal to a second signal corresponding to a desired luminance level of said backlight;
- (D) adjusting said first power level when said actual luminance level is not equal to said desired luminance level;
- and
- (E) automatically inputting a boost power level to said backlight when said first power level exceeds said control range.
A method for controlling the luminance of a backlight configured for operation in combination with an illuminated vehicular display, the method comprising:
- (A) supplying a first power level to said backlight, wherein said backlight is configured to output an actual luminance level;
- (B) sensing a signal corresponding to said actual brightness level;
- (C) based on said signal, determining whether said actual luminance level is equal to a predetermined desired luminance level;
- and
- (D) adjusting said power when it is determined that said actual luminance level is not equal to said desired luminance level for a predetermined amount of time.
Dependencies are inferred from the claim text.