Color correcting and ambient light responsive CRT system

• US 6,819,306 B1
• Filed: 04/12/1999
• Issued: 11/16/2004
• Est. Priority Date: 04/12/1999
• Status: Expired due to Fees

• Current Assignee: Sony Corporation (Sony Group Corp.), Sony Electronics Inc. (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.), Sony Electronics Inc. (Sony Group Corp.)
• Inventors: Cooper, Ted J.
• Primary Examiner(s): Tran, Henry N.
• Application Number:
  US09/290,461
• Time in Patent Office: 2,045 Days
• Field of Search: 345/22, 345/150, 345/152, 345/204, 345/207, 345/11, 345/77, 345/88, 345/214, 356/154, 356/389, 356/391, 356/416, 356/419, 356/425, 348/179, 348/210-236, 348/602, 348/325, 348/332, 348/655, 348/657, 348/658
• US Class Current: 345/22
• CPC Class Codes: G01J 3/50 using electric radiation detectors
• CPC Class Codes: G09G 2320/029 by monitoring one or more pixels in the display panel, e.g. by monitoring a fixed reference pixel
• CPC Class Codes: G09G 2320/0666 for control of colour parameters, e.g. colour temperature

Abstract

A light-emitting color display system is provided having an optical sensor system in which a plurality of photosensors are directed towards the light source of the light-emitting color display system to provide outputs proportional to the light energy associated with each color. A processing system responds to the outputs over time with the initial outputs and provides a mechanism to correct color changes in the display system. The color light-emitting display system has a second plurality of photosensors directed away from said light-emitting color display system for providing outputs related to the different illuminants and allowing compensation of the light-emitting color display system for the illuminants.

Claims

1. A light emitting color display system having an optical sensor system comprising:

a plurality of photosensors directed towards and away from said light emitting color display system for respectively providing a plurality of display and ambient color outputs proportional to the light energy applied thereto respectively from and away from said light emitting color display system, each of said plurality of photosensors associated with a color of light respectively from and away from said light emitting color display system;

a control system for controlling each color of light from said light emitting color display system; and

a processing system connected to said plurality of photosensors and said control system, said processing system responsive to said plurality of display and ambient color outputs to compare said plurality of display and ambient color outputs over time with an initial plurality of display and ambient color outputs and including a mechanism for providing information to allow compensation for color differences respectively from and away from said light emitting color display system over time.

2. The display system as claimed in claim 1 wherein:

said plurality of photosensors includes a plurality of bandpass filters for said plurality of photosensors, each of said plurality of bandpass filters having discrimination ability for portions of the color of light from said light emitting color display system and a spectrum of illumination selected from a group consisting of natural light, artificial light, and a combination thereof; and

said processing system responsive to said plurality of ambient color outputs to determine the presence of light energy attributable to illumination from the natural light, the artificial light, and the combination thereof, said processing system including a mechanism for providing information to said control system to allow compensation of color light emitted from said light emitting color display system due to illumination on said light emitting color display system.

3. The display system as claimed in claim 1 wherein:

the color display emits cyan, magenta, yellow, and green light; and

said plurality of photosensors includes one photosensor for each light.

4. The display system as claimed in claim 1 wherein:

the color display emits red, green, and blue light; and

said plurality of photosensors includes one photosensor for each light.

5. A cathode ray tube having a plurality of guns and color phosphors and having an optical sensor system comprising:

a plurality of photosensors directed towards and away from the cathode ray tube and adjacent the phosphors and opposite the guns for respectively providing a plurality of display and ambient color outputs proportional to the light energy applied thereto respectively from and away from the phosphors, each of said plurality of photosensors associated with a different color of light respectively from and away from said phosphors;

a control system for controlling each of said plurality of guns to control the color light energy from the phosphors; and

a processing system connected to said plurality of photosensors and said control system, said processing system responsive to said plurality of display and ambient color outputs to compare said plurality of display and ambient color outputs over time with an initial plurality of display and ambient color outputs and including a mechanism for providing information to allow compensation for color differences respectively from and away from the phosphors over time.

6. The cathode ray tube as claimed in claim 5 wherein:

said phosphors emit red, green, and blue light and said plurality of photosensors includes one photosensor for each light.

7. The cathode ray tube as claimed in claim 5 wherein:

said plurality of photosensors includes a plurality of bandpass filters for said plurality of photosensors, each of said plurality of bandpass filters having discrimination ability for portions of the color of light from said phosphors and a spectrum of illumination selected from a group consisting of natural light, artificial light, and a combination thereof; and

said processing system responsive to said plurality of ambient color outputs to determine the presence of light energy attributable to illumination from the natural light, the artificial light, and the combination thereof, said processing system including a mechanism for providing information to said control system to allow compensation of color light emitted from the phosphors due to illumination on said cathode ray tube.

8. The cathode ray tube as claimed in claim 7 wherein:

said plurality of bandpass filters have discrimination ability for portions of the spectrums of illumination selected from a group consisting of;

daylight,

afternoon light,

fluorescent,

incandescent,

photoflash, and

a combination thereof;

said processing system is responsive to said plurality of ambient color outputs to determine the presence of light energy attributable to illumination from;

daylight,

afternoon light,

fluorescent,

incandescent,

photoflash, and

combination thereof.