Method of adjusting white balance, white balance adjustment apparatus, and display device

1. A method of adjusting white balance, comprising:

a) acquiring a measurement value of a color value of white color, in a display device performing a white balance correction of correcting first to n th gradation values before a correction to be first to n th gradation values after the correction and displaying a displayed color in accordance the first to n th gradation values after the correction, n indicating an integral number of three or larger, in a case where the first to n th gradation values after the correction are first to n th specific gradation values for making the display device display white color, respectively, and the displayed color is white color;

b) calculating a shift amount between the measurement value of the color value of white color and a calculation value of a color value of white color derived from the first to n th specific gradation values;

c) performing a generation of a math formula for deriving a calculation value of a color value of a displayed color from the first to n th gradation values after the correction, the reflection of the shift amount being performed on the math formula so that the calculation value of a color value of a displayed color is brought close to a measurement value of a color value of a displayed color;

d) calculating first to n th gradation values after a white balance adjustment which the first to n th gradation values after the correction take, respectively, in a case where the calculation value of the color value of the displayed color is a target color value of white color in the math formula; and

e) adjusting contents of the white balance correction so that the first to n th gradation values after the correction are adjusted to the first to n th gradation values after the white balance adjustment, respectively, in a case where the first to n th gradation values before the correction are the first to n th specific gradation values, respectively.

2. The method of adjusting white balance according to claim 1 , wherein

the shift amount includes contribution of all the first to n th specific gradation values,

the math formula includes first to n th coefficients respectively indicating degrees of contribution of the first to n th gradation values after the correction to the calculation value of the color value of the displayed color, and

the reflection is performed by dividing the shift amount into first to n th correction amounts, respectively corresponding to contribution rates of the first to n th specific gradation values contributing to the correction amount, and respectively setting the first to n th correction amounts to be factors included in the first to n th coefficients.

3. The method of adjusting white balance according to claim 2 , wherein

the generation is performed by estimating an estimated shift amount between a measurement value of a color value of white color after the step e) is executed and a calculation value of a color value of white color derived from the first to n th specific gradation values, and then reducing the estimated shift amount.

4. The method of adjusting white balance according to claim 1 , wherein

the generation is performed by estimating an estimated shift amount between a measurement value of a color value of white color after the step e) is executed and a calculation value of a color value of white color derived from the first to n th specific gradation values, and then reducing the estimated shift amount.

5. A white balance adjustment apparatus, comprising:

a white color measurement value acquisition unit to acquire a measurement value of a color value of white color, in a display device performing a white balance correction of correcting first to n th gradation values before a correction to be first to n th gradation values after the correction and displaying a displayed color in accordance the first to n th gradation values after the correction, n indicating an integral number of three or larger, in a case where the first to n th gradation values after the correction are first to n th specific gradation values for making the display device display white color, respectively, and the displayed color is white color;

a shift amount calculation unit to calculate a shift amount between the measurement value of the color value of white color and a calculation value of a color value of white color derived from the first to n th specific gradation values;

a math formula generation unit to perform a generation of a math formula for deriving a calculation value of a color value of a displayed color from the first to n th gradation values after the correction, the reflection of the shift amounts being performed on the math formula so that the calculation value of a color value of a displayed color is brought close to a measurement value of a color value of a displayed color;

a gradation value calculation unit to calculate first to n th gradation values after a white balance adjustment which the first to n th gradation values after the correction take, respectively, in a case where the calculation value of the color value of the displayed color is a target color value of white color in the math formula; and

a white balance adjustment unit to adjust contents of the white balance correction so that the first to n th gradation values after the correction are adjusted to the first to n th gradation values after the white balance adjustment, respectively, in a case where the first to n th gradation values before the correction are the first to n th specific gradation values, respectively.

6. A display device, comprising:

a display mechanism performing a white balance correction of correcting first to n th gradation values before a correction to be first to n th gradation values after the correction and displaying a displayed color in accordance the first to n th gradation values after the correction, n indicating an integral number of three or larger;

a white color measurement value acquisition unit to acquire a measurement value of a color value of white color in a case where the first to n th gradation values after the correction are first to n th specific gradation values for making the display mechanism display white color, respectively, and the displayed color is white color;

a shift amount calculation unit to calculate a shift amount between the measurement value of the color value of white color and a calculation value of a color value of white color derived from the first to n th specific gradation values;

a math formula generation unit to perform a generation of a math formula for deriving a calculation value of a color value of a displayed color from the first to n th gradation values after the correction, the reflection of the shift amounts being performed on the math formula so that the calculation value of a color value of a displayed color is brought close to a measurement value of a color value of a displayed color;

a gradation value calculation unit to calculate first to n th gradation values after a white balance adjustment which the first to n th gradation values after the correction take, respectively, in a case where the calculation value of the color value of the displayed color is a target color value of white color in the math formula; and

a white balance adjustment unit to adjust contents of the white balance correction so that the first to n th gradation values after the correction are adjusted to the first to n th gradation values after the white balance adjustment, respectively, in a case where the first to n th gradation values before the correction are the first to n th specific gradation values, respectively.