Display apparatus and operating method thereof
A display apparatus includes a display panel including a plurality of pixels, each pixel of the plurality of pixels having a plurality of light-emitting devices; a storage configured to store a plurality of calibration matrices for each pixel of the plurality of pixels; a processor configured to identify a calibration matrix according to input data of the plurality of pixels and to calibrate modulation data corresponding to the input data based on the identified calibration matrix; and a panel driver configured to drive the display panel by applying a driving signal generated from the calibrated modulation data to the light-emitting devices of the plurality of pixels, wherein the plurality of calibration matrices includes a white calibration matrix and a color calibration matrix.
1. An apparatus for generating a calibration matrix, the apparatus comprising:
a measurer configured to, for each pixel among a plurality of pixels, measure a brightness and a chromaticity for each light-emitting device of a plurality of light-emitting devices within the pixel; and
a calibration matrix generator configured to, for each pixel among the plurality of pixels:
obtain a target brightness for each light-emitting device of the plurality of light-emitting devices corresponding to a white target brightness and a white target chromaticity, and
generate a plurality of pixel specific calibration matrices for the pixel based on the target brightness for each light-emitting device of the plurality of light-emitting devices, a target chromaticity of a light-emitting device on which a chromaticity calibration is to be performed, and the measured brightness and the measured chromaticity for each light-emitting device of the plurality of light-emitting devices,
wherein the calibration matrix is used to correct at least one of a brightness and a chromaticity of at least one light-emitting device included in the pixel so that the light-emitting device included in the pixel has a same color and brightness as a light-emitting device included in other pixels,
wherein the calibration matrix generator is further configured to, for each pixel among the plurality of pixels:
obtain a variable target brightness for each light-emitting device of the plurality of light-emitting devices based on a measured chromaticity of a light-emitting device on which a brightness calibration is to be performed and the target chromaticity of the light-emitting device on which the chromaticity calibration is to be performed,
obtain a fixed target brightness for each light-emitting device of the plurality of light-emitting devices based on a target chromaticity for each light-emitting device of the plurality of light-emitting devices,
generate a pixel specific white calibration matrix from the variable target brightness, and
generate a pixel specific color calibration matrix from the fixed target brightness.
2. The apparatus of claim 1 , wherein the light-emitting device on which the brightness calibration is to be performed corresponds to a blue light-emitting diode (LED).
3. The apparatus of claim 1 , wherein a target chromaticity of a blue light emitting diode (LED) is obtained from measured chromaticities of a plurality of blue LEDs.
4. The apparatus of claim 1 , wherein the measurer is further configured to, for each pixel among the plurality of pixels, measure a plurality of brightnesses in a plurality of gradations including a low gradation and a high gradation, and
wherein the calibration matrix generator is further configured to, for each pixel among the plurality of pixels, generate a pixel specific white calibration matrix and a pixel specific color calibration matrix for each gradation of the plurality of gradations based on the plurality of measured brightnesses in the plurality of gradations.
5. The apparatus of claim 4 , wherein the calibration matrix generator is further configured to, for each pixel among the plurality of pixels:
generate a pixel specific interpolation white calibration matrix by interpolating the pixel specific white calibration matrix generated for each gradation of the plurality of gradations, and
generate a pixel specific interpolation color calibration matrix by interpolating the pixel specific color calibration matrix generated for each of the plurality of gradations.
6. A method of generating a calibration matrix, the method comprising:
measuring, for each pixel among a plurality of pixels, a brightness and a chromaticity for each light-emitting device of a plurality of light-emitting devices within the pixel;
obtaining, for each pixel among the plurality of pixels, a target brightness for each light-emitting device of the plurality of light-emitting devices based on a white target brightness and a white target chromaticity; and
generating, for each pixel among the plurality of pixels, a plurality of pixel specific calibration matrices for the pixel based on the target brightness for each light-emitting device of the plurality of light-emitting devices, a target chromaticity of a light-emitting device on which a chromaticity calibration is to be performed, and the measured brightness and the measured chromaticity for each light-emitting device of the plurality of light-emitting devices,
wherein the calibration matrix is used to correct at least one of a brightness and a chromaticity of at least one light-emitting device included in the pixel so that the light-emitting device included in the pixel has a same color and brightness as a light-emitting device included in other pixels,
wherein the obtaining of the target brightness for each of the plurality of light-emitting devices comprises:
obtaining a variable target brightness for each light-emitting device of the plurality of light-emitting devices based on a measured chromaticity of a light-emitting device on which a brightness calibration is to be performed and the target chromaticity of the light-emitting device on which the chromaticity calibration is to be performed; and
obtaining a fixed target brightness for each of the plurality of light-emitting devices based on a target chromaticity for each of the plurality of light-emitting devices, and
wherein the generating of the plurality of pixel specific calibration matrices comprises:
generating a white calibration matrix from the variable target brightness; and
generating a color calibration matrix from the fixed target brightness.
7. The method of claim 6 , wherein the light-emitting device on which the brightness calibration is to be performed corresponds to a blue light-emitting diode (LED) device.
8. The method of claim 7 , wherein a target chromaticity of the blue LED is obtained from measured chromaticities of a plurality of blue LEDs.
9. The method of claim 6 , wherein the measuring, for each pixel among the plurality of pixels, the brightness for each of the plurality of light-emitting devices comprises measuring a plurality of brightnesses in a plurality of gradations including a low gradation and a high gradation, and
wherein the generating of the plurality of pixel specific calibration matrices, for each pixel among the plurality of pixels, comprises generating a white calibration matrix and a color calibration matrix for each of the plurality of gradations, based on the plurality of measured brightnesses in the plurality of gradations.