Display device and driving method thereof

1. A display device comprising:

a display panel which displays an image;

a light source unit which provides light to the display panel; and

a light source controller which transmit a control signal to the light source unit,

wherein the light source unit includes a light source including a plurality of light emission blocks,

wherein the light source controller includes:

a first reference determining unit which determines first references for the plurality of the light emission blocks based on an input image signal,

a reference difference calculator which calculates at least one reference difference for neighboring light emission blocks by using first references for corresponding neighboring light emission blocks,

a parameter generator which generates at least one parameter by using the at least one reference difference, and

a second reference determining unit which determines a second reference for a corresponding light emission block by using the first references for the plurality of light emission blocks and the at least one parameter, and

wherein

the at least one reference difference is determined as an absolute value of a difference between the first references of the neighboring light emission blocks, or an n square (n is a natural number larger than 1) of the difference between the first references of the neighboring light emission blocks.

2. The display device of claim 1 , wherein

the parameter generator normalizes the at least one reference difference for the neighboring light emission blocks to generate the at least one parameter corresponding to the neighboring light emission blocks.

3. The display device of claim 1 , wherein the second reference determining unit

determines a first value by multiplying a parameter, which corresponds to a first light emission block and a second light emission block neighboring the first light emission block, by the first reference of the first light emission block,

determines a second value as the first reference of the second light emission block, and

compares the first value and the second value to determine the second reference of the second light emission block.

4. The display device of claim 1 , wherein

the parameter generator includes at least one of,

a weight value look-up table which stores at least one weight value respectively corresponding to the neighboring light emission blocks, and

a multiplier which multiplies the at least one reference difference by a corresponding weight value to obtain at least one weighted reference.

5. The display device of claim 4 , wherein

the parameter generator normalizes the at least one weighted reference calculated for the neighboring light emission blocks to generate the at least one parameter corresponding to the neighboring light emission blocks.

6. The display device of claim 1 , wherein the second reference determining unit

determines a first value by multiplying a parameter, which corresponds to a first light emission block and a second light emission block neighboring the first light emission block, by the first reference of the first light emission block,

determines a second value as the first reference of the second light emission block, and

compares the first value and the second value to determine the second reference of the second light emission block.

7. The display device of claim 4 , wherein

the parameter generator further includes an adding unit which adds the at least one weighted reference.

8. The display device of claim 7 , wherein

the parameter generator generates one single parameter by using an output of the adding unit.

9. The display device of claim 1 , wherein the second reference determining unit

determines a first value by multiplying the single parameter by the first reference of a first light emission block,

determines a second value as the first reference of a second light emission block neighboring the first light emission block, and

compares the first value and the second value to determine the second reference of the second light emission block.

10. The display device of claim 1 , wherein

the plurality of the light emission blocks are arranged in an n×m matrix.

11. The display device of claim 10 , wherein

the parameter generator includes at least one of,

a weight value look-up table which stores at least one weight value respectively corresponding to the neighboring light emission blocks, and

a multiplier which multiplies the at least one reference difference by a corresponding weight value to obtain at least one weighted reference, and wherein

two light emission blocks neighboring in a row direction or a column direction in a 2×2 matrix have an identical weight value.

12. A method of driving a display device, the method comprising:

determining first references for a plurality of light emission blocks based on an input image signal;

calculating at least one reference difference for neighboring light emission blocks by using first references for corresponding neighboring light emission blocks;

generating at least one parameter by using the at least one reference difference;

determining a second reference for a corresponding light emission block by using the first references for the plurality of the light emission blocks and the at least one parameter; and

providing a driving signal to the plurality of the light emission blocks based on the second reference,

wherein

the display device includes a light source including the plurality of the light emission blocks and a display panel which is provided with light by the light source, and

the at least one reference difference is determined as an absolute value of a difference between the first references of the neighboring light emission blocks or an n square (n is a natural number larger than 1) of the difference between the first references of the neighboring light emission blocks.

13. The method of claim 12 , wherein

the generating the at least one parameter includes normalizing the at least one reference difference for the neighboring light emission blocks to generate the at least one parameter corresponding to the neighboring light emission blocks.

14. The method of claim 12 , wherein

the generating the at least one parameter includes:

multiplying the at least one reference difference for the neighboring light emission blocks by at least one weight value corresponding to the neighboring light emission blocks to calculate at least one weighted reference; and

normalizing the at least one weighted reference to generate at least one parameter corresponding to the neighboring light emission blocks.

15. The method of claim 14 , wherein

the generating the at least one parameter further includes:

adding the at least one weighted reference; and

generating one single parameter by using an addition result.

16. The method of claim 12 , wherein

the determining the second reference includes,

determining a first value by multiplying the at least one parameter by the first reference of a first light emission block,

determining a second value as the first reference of a second light emission block neighboring the first light emission block, and

comparing the first value and the second value to determine the second reference of the second light emission block.