CRT calibration device for calibrating display color of a CRT to a color standard

• US 5,619,349 A
• Filed: 12/19/1994
• Issued: 04/08/1997
• Est. Priority Date: 12/27/1993
• Status: Expired due to Term

• Current Assignee: Brother Kogyo Kabushiki Kaisha (Brother Industries Limited)
• Original Assignee: Brother Kogyo Kabushiki Kaisha (Brother Industries Limited)
• Inventors: Ueda, Masashi, Komiya, Ryohei
• Primary Examiner(s): BRINICH, STEPHEN M
• Application Number:
  US08/358,256
• Time in Patent Office: 841 Days
• Field of Search: 358/504, 358/514-521, 358/296, 358/298, 355/77, 355/83, 355/88
• US Class Current: 358/521
• CPC Class Codes: H04N 1/4078 using gradational references, e.g. grey-scale test pattern analysis
• CPC Class Codes: H04N 1/6011 with simulation on a subsidiary picture reproducer H04N1/622 takes precedence; matching two or more picture reproducers H04N1/6052
• CPC Class Codes: H04N 17/02 for colour television signals
• CPC Class Codes: H04N 17/04 for receivers
• CPC Class Codes: H04N 9/69 for modifying the colour signals by gamma correction controlling camera response for colour signals H04N23/83

Abstract

In a CRT calibration device, gradation signals of plural colors displayed on a CRT are determined in a gradation signal calculator based on a γ value input from a keyboard and data from a luminance value storage unit storing a plurality of relative luminance values on the CRT. If a user wants to correct the γ value while seeing the plural colors displayed on the CRT, he inputs a correct γ value through the keyboard.

Claims

1. A CRT calibration device for calibrating display colors of a CRT to a color standard, the device comprising:

input means for inputting a gradation reproduction characteristic value of the CRT;

storage means for storing relative luminance data of the CRT;

determining means for determining a gradation signal value of the CRT based on the gradation reproduction characteristic value input by said input means and the relative luminance data stored in said storage means; and

display control means for controlling a color display based on the gradation signal value determined by said determining means, the color display indicating when an actual CRT gradation reproduction characteristic value approximately equals the gradation reproduction characteristic value input by said input means.

2. The CRT calibration device of claim 1, wherein the data stored in said storage means comprises values indicating a gradation of an achromatic color which varies from white to black.

3. The CRT calibration device of claim 1, wherein the data stored in said storage means comprises values for varying a gradation level of at least one of a plurality of primary colors of the CRT.

4. The CRT calibration device of claim 1, wherein the data stored in said storage means comprises values representative of a gradation in at least one of a light portion and a dark portion of a gradation reproduction range displayable on the CRT.

5. The CRT calibration device of claim 4, wherein the data stored in said storage means comprises values representative of the gradation in both the light portion and the dark portion of the gradation reproduction range displayable on the CRT.

6. The CRT calibration device of claim 1, further including:

color conversion means for performing color conversion on image data displayed on the CRT based on the color standard; and

color-conversion correcting means for correcting the color-conversion of said color conversion means based on the gradation reproduction characteristic input by said input means.

7. A CRT calibration device for calibrating display colors of a CRT to a color standard, the device comprising:

an input device inputting a gradation reproduction characteristic value of the CRT;

a memory storing relative luminance data of the CRT;

a gradation signal calculator determines a gradation signal value of the CRT based on the gradation reproduction characteristic value input by said input device and the relative luminance data stored in said memory; and

a display controller controlling a color display based on the gradation signal value generated by said gradation signal generator, the color display indicating when an actual CRT gradation reproduction characteristic value approximately equals the gradation reproduction characteristic value input by said input device.

8. The CRT calibration device of claim 7, wherein the data stored in said memory comprises values indicating a gradation of an achromatic color which varies from white to black.

9. The CRT calibration device of claim 7, wherein the data stored in said memory comprises values for varying a gradation level of at least one of a plurality of primary colors of the CRT.

10. The CRT calibration device of claim 7, wherein the data stored in said memory comprises values representative of a gradation in at least one of a light portion and a dark portion of a gradation reproduction range displayable on the CRT.

11. The CRT calibration device of claim 10, wherein the data stored in said memory comprises values representative of the gradation in both the light portion and the dark portion of the gradation reproduction range displayable on the CRT.

12. The CRT calibration device of claim 7, further including:

a color converter converting color of image data displayed on the CRT when the image data are transmitted to a printer; and

a color-conversion corrector correcting the color-conversion of said color converter based on the gradation reproduction characteristic input by said input device.

13. A method for calibrating display colors of a CRT to a color standard, the method comprising the steps of:

inputting a gradation reproduction characteristic value of the CRT;

storing relative luminance data of the CRT;

determining a gradation signal value of the CRT based on the input gradation reproduction characteristic value and the stored relative luminance data; and

controlling a color display based on the determined gradation signal value, the color display indicating when an actual CRT gradation reproduction characteristic value approximately equals the input gradation reproduction characteristic value.

14. The CRT calibration method of claim 13, wherein the stored at least one relative luminance value comprises values indicating a gradation of an achromatic color which varies from white to black.

15. The CRT calibration method of claim 13, wherein the stored at least one relative luminance value comprises values for varying a gradation level of at least one of a plurality of primary colors of the CRT.

16. The CRT calibration device of claim 13, wherein the stored at least one relative luminance value comprises values representative of a gradation in at least one of a light portion and a dark portion of a gradation reproduction range displayable on the CRT.

17. The CRT calibration method of claim 13, further comprising the steps of:

performing color conversion on image data displayed on the CRT based on the color standard; and

correcting the color-conversion of said color conversion means based on the input gradation reproduction characteristic.

18. The CRT calibration method of claim 17, further comprising the step of transmitting the image data to one of a printer, another display device, and a memory.