Patent ID: 8502811
Filing Date: 2013-08-06
Classification: G09G

Abstract:
1. A pixel driving device that drives a plurality of pixels, wherein each of the plurality of pixels includes: (i) a light emitting element; and (ii) a pixel driving circuit comprising a driving device having a first end of a current path connected to a first end of the light emitting element and having a second end of the current path to which a power-source voltage is applied, the pixel driving device comprising: a voltage control circuit that sets a voltage of a second end of the light emitting element of each pixel; a plurality of voltage obtaining circuits respectively provided for each of a plurality of data lines, wherein each data line is connected to each pixel, and each voltage obtaining circuit obtains a voltage value of each data line; a plurality of voltage applying circuits respectively provided for each data line, wherein each voltage applying circuit outputs a predetermined voltage; and a correction-data obtaining function circuit that obtains a characteristic parameter including a threshold voltage of the driving device of each pixel based on the voltage value of each data line obtained by each voltage obtaining circuit with the voltage of the second end of the light emitting element of each pixel being set to be a setting voltage by the voltage control circuit, wherein the setting voltage is set based on the voltage value of each data line obtained by each voltage obtaining circuit at a predetermined timing, wherein the predetermined timing is a timing after the voltage of the second end of the light emitting element of each pixel is set to be an initial voltage by the voltage control circuit, a first detection voltage is applied to each data line by each voltage applying circuit, and a current is caused to flow through the current path of the driving device through each data line, wherein the initial voltage is set to be a same voltage as the power-source voltage or a voltage having a lower electric potential than the power-source voltage and having an electric potential difference from the power-source voltage smaller than a light emission threshold voltage of the light emitting element, wherein each voltage applying circuit is connected to each data line when the correction-data obtaining function circuit obtains the characteristic parameter, and applies, to each data line, a second detection voltage that causes a voltage across the first and second ends of the current path of the driving device to be larger than the threshold voltage of the driving device, wherein each voltage obtaining circuit obtains, as a plurality of measurement voltages, a plurality of voltage values of each data line at a plurality of different timings after a connection between each data line and each voltage applying circuit is disconnected, and wherein the correction-data obtaining function circuit obtains, as the characteristic parameter, a first characteristic parameter of the pixel driving circuit including the threshold voltage of the driving device of each pixel and a second characteristic parameter relating to a current amplification factor of the pixel driving circuit based on the voltage values of the measurement voltages obtained by each voltage obtaining circuit.