Compact Flat Panel Color Calibration System

• US 20090051711A1
• Filed: 07/29/2008
• Published: 02/26/2009
• Est. Priority Date: 12/08/2000
• Status: Active Grant

• Current Assignee: RPX Corporation
• Original Assignee: Silicon Graphics Incorporated (Graphics Properties Holdings, Inc.)
• Inventors: Meng, Alice T., Ingulsrud, Joel, Granger, Ed, Evanicky, Daniel
• Granted Patent: US 8,179,405 B2
• Time in Patent Office: Days
• US Class Current: 345/690
• CPC Class Codes: G09G 2320/0606 Manual adjustment
• CPC Class Codes: G09G 2320/0626 for control of overall brightness
• CPC Class Codes: G09G 2320/0666 for control of colour parameters, e.g. colour temperature
• CPC Class Codes: G09G 2320/0673 for control of gamma adjustment, e.g. selecting another gamma curve
• CPC Class Codes: G09G 2320/0693 Calibration of display systems
• CPC Class Codes: G09G 2340/0407 Resolution change, inclusive of the use of different resolutions for different screen areas
• CPC Class Codes: G09G 2360/145 the light originating from the display screen
• CPC Class Codes: G09G 3/006 Electronic inspection or testing of displays and display drivers, e.g. of LED or LCD displays testing individual LED's G01R31/2635; testing lamps G01R31/44; testing of optical features of LCD displays G02F1/1309
• CPC Class Codes: G09G 3/20 for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
• CPC Class Codes: G09G 3/3648 using an active matrix G09G3/367 - G09G3/3696 take precedence
• CPC Class Codes: G09G 5/005 Adapting incoming signals to the display format of the display terminal
• CPC Class Codes: G09G 5/006 Details of the interface to the display terminal specific for a display terminal using a CRT G09G1/167; using a flat panel G09G3/2096; circuits for interfacing with colour displays G09G5/04
• CPC Class Codes: H04N 17/02 for colour television signals
• CPC Class Codes: H04N 17/04 for receivers
• CPC Class Codes: H04N 9/30 using solid-state colour display devices

Abstract

A compact flat panel color calibration system includes a lens prism optic able to pass a narrow, perpendicular, and uniform cone angle of incoming light to a spectrally non-selective photodetector. The calibration system also includes a microprocessor operable to determine the luminance of the display based upon the information gathered by the photodetector. A software module included in the calibration system is then operable to process the luminance information in order to adjust the flat panel display.

Claims

1. A method of calibrating a display, comprising:

instructing a sensor system to measure a luminance level of a splash screen generated on a display;

receiving the luminance level of the splash screen; and

providing control information to a backlight driver to set the luminance level on a backlight of the display.

2. The method of claim 1 wherein the splash screen is a gray scale splash screen.

3. The method of claim 1 wherein the display includes a liquid crystal module.

4. The method of claim 1 wherein the control information is provided through to the backlight driver through a backlight application programming interface.

5. The method of claim 1 further comprising:

providing control information to the backlight driver to set a white balance level on the backlight of the display.

6. The method of claim 1 further comprising:

calculating a gamma value to load into a lookup table for the display.

7. A method of calibrating a display, comprising:

setting an illumination level of a first illumination lamp to its minimum illumination level and recording a first minimum input signal from a power source to the first illumination lamp;

setting an illumination level of a second illumination lamp to its minimum illumination level and recording a second minimum input signal from the power source to the second illumination lamp;

increasing the illumination level of the first illumination lamp to its maximum illumination level and recording a first maximum input signal from the power source to the first illumination lamp;

increasing the illumination level of the second illumination lamp to its maximum illumination level and recording a second maximum input signal from the power source to the second illumination lamp;

determining the difference between the first and second minimum input signals;

determining the difference between the first and second maximum input signals; and

using the differences in the minimum and maximum input signals to map the illumination levels of the first and second illumination lamps as functions of the input signals.