Patent ID: 8199074

Claim:
A system for reducing mura defects, comprising: a pixel array comprising a plurality of pixels, each of the pixels comprising an organic light emitting element equipped with a sensing unit which is operative to retrieve display information responsive to the organic light emitting element when the organic light emitting unit emits according to a test signal, wherein the test signal is a fixed signal; a conversion circuit operative to determine a display parameter of each organic light emitting element according to the test signal and the display information of each organic light emitting element, wherein the conversion circuit comprises: a comparison device generating the display parameter according to the test signal and the display information of each organic light emitting element; and an analog-to-digital converter converting the display parameter from analog to digital; a memory device operative to store the display parameter of each organic light emitting element; and a compensation circuit operative to modify a video signal to drive the pixel array in accordance with the display parameters stored in the memory device, wherein the compensation circuit comprises: a correcting device modifying the video signal; and a digital-to-analog converter converting the modified video signal; wherein the sensing units monitor real light of the organic light emitting elements to form the display information, wherein the pixel array further comprises: a driving transistor comprising a gate, a first source and a first drain, wherein the first source or the first drain is connected to a power source line and the other to the organic light emitting element; and a switching transistor comprising a gate connected to a first scan line, a second source and a second drain, wherein the second source or the second drain is connected to a first data line and the other connected to the gate of the driving transistor, wherein the conversion circuit does not directly connect to the first data line; and wherein the sensing unit comprises a thin film transistor comprising a gate connected to a second scan line, a third source and a third drain, the third source or the third drain is connected to the organic light emitting element and the other to a second data line.