Method of driving a light source, method of displaying an image using the same, and display apparatus for performing the same

1. A method of driving a light source, comprising:

converting a reference luminance value of the light source to a first just noticeable difference (JND) value, JND values representing a minimum noticeable difference between two stimuli;

determining a second JND value by subtracting a JND reference value from the first JND value, the JND reference value being determined based on a time required for a human to notice a luminance change according to a JND value;

determining a target luminance value using the second JND value, the target luminance value being lower than the reference luminance value; and

generating a first driving signal using the target luminance value, the first driving signal to be applied to the light source.

2. A method of driving a light source, comprising:

converting a reference luminance value of the light source to a first lust noticeable difference (JND) value, JND values representing a minimum noticeable difference between two stimuli;

determining a target luminance value using the first JND value, the target luminance value being lower than the reference luminance value;

generating a first driving signal using the target luminance value, the first driving signal to be applied to the light source;

generating a second driving signal using the reference luminance value, the second driving signal to be applied to the light source; and

outputting the first driving signal and the second driving signal according to a power source mode.

3. The method of claim 2 , wherein the first driving signal is outputted when the power source mode is a battery mode, the second driving signal is outputted when the power source mode is an external power source mode, and a level of the second driving signal is greater than a level of the first driving signal.

4. The method of claim 3 , wherein the first driving signal and the second driving signal are alternately outputted in response to the battery mode.

5. The method of claim 4 , wherein the first driving signal is continuously outputted in response to a user input signal to output the first driving signal, and the first driving signal is outputted in response to the user input signal or when a reference interval expires without receiving the user input signal.

6. A method of displaying an image, comprising:

analyzing an input image to compensate a color temperature of the input image;

displaying the compensated input image on a display panel;

converting a reference luminance value of a light source to a first just noticeable difference (JND) value, the light source configured to provide light to the display panel, and JND values representing a minimum noticeable difference between two stimuli;

determining a second JND value by subtracting a JND reference value from the first JND value, the JND reference value being determined based on a time required for a human to notice a luminance change according to a JND value;

determining a target luminance value that is less than the reference luminance value using the second JND value;

generating a first driving signal using the target luminance value and applying the first driving signal to the light source; and

providing the light to the display panel in response to the first driving signal.

7. A method of displaying an image, comprising:

analyzing an input image to compensate a color temperature of the input image;

compensating a color temperature of the input image by increasing the color temperature of an achromatic color image comprising a grayscale greater than or equal to a reference grayscale when a ratio of the achromatic color image in the input image is greater than a reference ratio;

displaying the compensated input image on a display panel;

converting a reference luminance value of a light source to a first lust noticeable difference (JND) value, the light source configured to provide light to the display panel, and JND values representing a minimum noticeable difference between two stimuli;

determining a target luminance value lower than the reference luminance value using the first JND value;

generating a first driving signal using the target luminance value and applying the first driving signal to the light source; and

providing the light to the display panel in response to the first driving signal.

8. A method of displaying an image, comprising:

analyzing an input image to compensate a color temperature of the input image;

displaying the compensated input image on a display panel;

converting a reference luminance value of a light source to a first just noticeable difference (JND) value, the light source configured to provide light to the display panel, and JND values representing a minimum noticeable difference between two stimuli;

determining a target luminance value lower than the reference luminance value using the first JND value;

generating a first driving signal using the target luminance value and applying the first driving signal to the light source;

generating a second driving signal using the reference luminance value, the second driving signal to be applied to the light source;

outputting the first driving signal and the second driving signal according to a power source mode; and

providing the light to the display panel in response to the first driving signal and the second driving signal.

9. The method of claim 8 , wherein the first driving signal is outputted when the power source mode is a battery mode, the second driving signal is outputted when the power source mode is an external power source mode, and a level of the second driving signal is greater than a level of the first driving signal.

10. The method of claim 9 , wherein the first driving signal and the second driving signal are alternately outputted in response to the battery mode.

11. The method of claim 10 , wherein the first driving signal is continuously outputted in response to a user input signal to output the first driving signal, and the first driving signal is outputted in response to the user input signal or when a reference interval expires without receiving the user input signal.

12. A display apparatus, comprising:

a display panel to display an image;

a light source part comprising a light source configured to provide light to the display panel;

a luminance determining part to convert a reference luminance value of the light source to a first just noticeable difference (JND) value, to determine a second JND value by subtracting a JND reference value from the first JND value, and to determine a target luminance value using the second JND value, the target luminance value being lower than the reference luminance value, and the JND values representing a minimum noticeable difference between two stimuli; and

a light source driver to generate a first driving signal corresponding to the target luminance value and to apply the first driving signal to the light source,

wherein the JND reference value is determined based on a time required for a human to notice a luminance change according to a JND value.

13. A display apparatus comprising:

a display panel to display an image;

a light source part comprising a light source configured to provide light to the display panel;

a luminance determining part to convert a reference luminance value of the light source to a first lust noticeable difference (JND) value and to determine a target luminance value using the first JND value, the target luminance value being lower than the reference luminance value, and JND values representing a minimum noticeable difference between two stimuli; and

a light source driver to generate a first driving signal corresponding to the target luminance value and to apply the first driving signal to the light source; and

a light source controller to output the reference luminance value and the target luminance value to the light source driver according to a power source mode,

wherein the light source driver generates a second driving signal corresponding to the reference luminance value.

14. The display apparatus of claim 13 , further comprising:

a color temperature compensator to compensate a color temperature of an achromatic color image comprising a grayscale greater than or equal to a reference grayscale when a ratio of the achromatic color image in the input image is greater than a reference ratio.

15. The display apparatus of claim 13 , wherein the light source controller outputs the target luminance value when the power source mode is a battery mode, and the light source controller outputs the reference luminance value when the power source mode is an external power source mode.

16. The display apparatus of claim 13 , wherein the light source controller alternately outputs the reference luminance value and the target luminance value when the power source mode is a battery mode.

17. The display apparatus of claim 16 , wherein the light source controller continuously outputs the target luminance value in response to a user input signal to output the target luminance value, and the light source controller continuously outputs the target luminance value in response to the user input signal or when a reference interval expires without receiving the user input signal.