Display driving apparatus having Mura compensation function and method of compensating for Mura of the same
The present disclosure discloses a display driving apparatus having a mura compensation function and a method of compensating for mura of the same. To this end, the display driving apparatus may include a mura memory in which compensation data corresponding to coefficient values of a mura compensation equation is stored, and a mura compensation circuit configured to perform mura compensations on display data by using the mura compensation equation to which the compensation data has been applied.
1. A display driving apparatus having a mura compensation function, comprising:
a mura memory in which compensation data corresponding to coefficient values of a mura compensation equation is stored; and
a mura compensation circuit configured to perform mura compensations on display data by using the mura compensation equation to which the compensation data has been applied,
wherein the coefficient values are set so that the mura compensation equation has been fit to have a curve that satisfies known difference values of selected gray levels, a first estimation difference value of a first estimation gray level higher than the selected gray levels, and a second estimation difference value of a second estimation gray level lower than the selected gray levels, and
wherein the compensation data comprises the coefficient values of the mura compensation equation in which all of the known difference values of the selected gray levels, the first estimation difference value, and the second estimation difference value have a difference within a preset error range.
2. The display driving apparatus of claim 1 , wherein the first estimation difference value and the second estimation difference value are values generated through extrapolation which uses the known difference values of the selected gray levels and which is performed by using a multilayer perceptron method.
3. The display driving apparatus of claim 1 , wherein:
the first estimation difference value is a value generated through first extrapolation,
the second estimation difference value is a value generated through second extrapolation,
the first extrapolation is configured to:
set a first difference value of a first selection gray level that is highest, among the selected gray levels, as a first target value, and calculate a first training value of the first selection gray level based on the known difference values of remaining selected gray levels by using a multilayer perceptron method,
store first weights for nodes for each layer of the multilayer perceptron method of generating the first training value close to the first target value in a way to satisfy the first target value, and
generate the first estimation difference value of the first estimation gray level by using the multilayer perceptron method to which the first weights have been applied, and
the second extrapolation is configured to:
set a second difference value of a second selection gray level that is lowest, among the selected gray levels, as a second target value, and calculate a second training value of the second selection gray level based on the known difference values of remaining selected gray levels by using a multilayer perceptron method,
store second weights for nodes for each layer of the multilayer perceptron method of generating the second training value close to the second target value in a way to satisfy the second target value, and
generate the second estimation difference value of the second estimation gray level by using the multilayer perceptron method to which the second weights have been applied.
4. The display driving apparatus of claim 3 , wherein:
the first training value close to the first target value in a way to satisfy the first target value has a difference within a preset first error range on the basis of the first target value, and
the second training value close to the second target value in a way to satisfy the second target value has a difference within a preset second error range on the basis of the second target value.
5. The display driving apparatus of claim 1 , wherein:
the first estimation gray level is a maximum gray level in a gray level range, and
the second estimation gray level is a minimum gray level in the gray level range.
6. A mura compensation method of a display driving apparatus, comprising:
a first step of performing first extrapolation for calculating a first estimation difference value of a first estimation gray level higher than selected gray levels by using known difference values of the selected gray levels;
a second step of performing second extrapolation for calculating a second estimation difference value of a second estimation gray level lower than the selected gray levels by using the known difference values of the selected gray levels; and
a third step of generating, as compensation data, coefficient values of a mura compensation equation which has been fit to have a curve that satisfies the known difference values of the selected gray levels, the first estimation difference value, and the second estimation difference value,
wherein the compensation data comprises the coefficient values of the mura compensation equation in which all of the known difference values of the selected gray levels, the first estimation difference value, and the second estimation difference value have a difference within a preset error range.
7. The mura compensation method of claim 6 , wherein the first estimation difference value and the second estimation difference value are calculated by using the known difference values of the selected gray levels and are calculated by using a multilayer perceptron method.
8. The mura compensation method of claim 6 , wherein:
the first extrapolation is configured to:
set a first difference value of a first selection gray level that is highest, among the selected gray levels, as a first target value, and calculate a first training value of the first selection gray level based on the known difference values of remaining selected gray levels by using a multilayer perceptron method,
store first weights for nodes for each layer of the multilayer perceptron method of generating the first training value close to the first target value in a way to satisfy the first target value, and
generate the first estimation difference value of the first estimation gray level by using the multilayer perceptron method to which the first weights have been applied, and
the second extrapolation is configured to:
set a second difference value of a second selection gray level that is lowest, among the selected gray levels, as a second target value, and calculate a second training value of the second selection gray level based on the known difference values of remaining selected gray levels by using a multilayer perceptron method,
store second weights for nodes for each layer of the multilayer perceptron method of generating the second training value close to the second target value in a way to satisfy the second target value, and
generate the second estimation difference value of the second estimation gray level by using the multilayer perceptron method to which the second weights have been applied.
9. The mura compensation method of claim 8 , wherein:
the first training value close to the first target value in a way to satisfy the first target value has a difference within a preset first error range on the basis of the first target value, and
the second training value close to the second target value in a way to satisfy the second target value has a difference within a preset second error range on the basis of the second target value.
10. The mura compensation method of claim 6 , wherein:
the first estimation gray level is a maximum gray level in a gray level range, and
the second estimation gray level is a minimum gray level in the gray level range.