# US 8,465,335 B2 · Color calibration system for a video display

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 8,465,335 B2
- Document ID: US8465335B2
- Status: Granted
- Kind: B2
- Application number: 13/588,788
- Filed: 2012-08-17
- Published: 2012-12-06
- Granted: 2013-06-18
- Earliest claimed: 2008-06-13
- Assignees: Barco N.V.
- Applicants: Grant Arthur John Elliott
- Inventors: Grant Arthur John Elliott
- Web page: https://patentgrep.com/patent/US8465335B2

## CPC

- G06F 3/1446: {display composed of modules, e.g. video walls}
- F21S 2/005: {of modular construction}
- F21V 21/088: Clips; Clamps
- G01J 3/28: Investigating the spectrum (using colour filters G01J3/51)
- G06F 1/00: Details not covered by groups G06F3/00 - G06F13/00 and G06F21/00 (architectures of general purpose stored program computers G06F15/76)
- G06F 3/017: {Gesture based interaction, e.g. based on a set of recognized hand gestures (interaction based on gestures traced on a digitiser G06F3/04883)}
- G06F 3/0304: {Detection arrangements using opto-electronic means (constructional details of pointing devices not related to the detection arrangement using opto-electronic means G06F3/033; optical digitisers G06F3/042)}
- G09F 9/3026: {Video wall, i.e. stackable semiconductor matrix display modules (video wall control systems G06F3/1446, G09G2300/026)}
- G09F 9/33: being semiconductor devices, e.g. diodes
- Y10T 29/49826: Assembling or joining
- G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N)
- F21S: NON-PORTABLE LIGHTING DEVICES; SYSTEMS THEREOF; VEHICLE LIGHTING DEVICES SPECIALLY ADAPTED FOR VEHICLE EXTERIORS
- F21V: FUNCTIONAL FEATURES OR DETAILS OF LIGHTING DEVICES OR SYSTEMS THEREOF; STRUCTURAL COMBINATIONS OF LIGHTING DEVICES WITH OTHER ARTICLES, NOT OTHERWISE PROVIDED FOR
- G01J: MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY (light sources F21, H01J, H01K, H05B; investigating properties of materials by optical means G01N)
- G09F: DISPLAYING; ADVERTISING; SIGNS; LABELS OR NAME-PLATES; SEALS
- Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION

## Abstract

Large digital displays for entertainment, architectural and advertising displays have interconnected display panels with pluralities of light emitting elements. To solve calibration problems, each of the display panels stores measured luminance and chromaticity data for each of the light emitting elements of the panel. The luminance data is independent of the chromaticity data. A central controller can then perform calibration procedures so that the light emitting elements are matched across the entire display.

## Claims

### Claim 1

A method of calibrating a light emitting element within a display, the method comprising:
measuring a normalized power spectral density (NPSD) of the light emitting element and storing the measured NPSD in the display;
measuring a luminance of the light emitting element;
storing the measured luminance in the display;
determining a transformation matrix for the light emitting element based on the measured NPSD, the measured luminance of the light emitting element, and a target color space; and
adjusting an output signal of the light emitting element based on the transformation matrix.

### Claim 2 (depends on 1)

The method of claim 1 further comprising:
adjusting the gain of the light emitting element based on the measured luminance in order to normalize a white point of the display.

### Claim 3 (depends on 1)

The method of claim 1 further comprising:
verifying the calibration of the light emitting element.

### Claim 4 (depends on 1)

The method of claim 1 wherein the light emitting element comprises an LED.