Patent ID: 9697771
Date: 2017-07-04
CPC Classifications: G09G

Claim:
1. A method of determining at least one characteristic of an organic light emitting device (OLED) in a selected pixel in an array of pixels in a display in which each pixel includes a supply voltage source, a drive transistor coupling said supply voltage source to an OLED for controlling the supply of current to the OLED from said supply voltage source, said display system including a plurality of monitor lines each of which is controllably coupled to two pixels at a node between said drive transistor and said OLED in each of said two pixels, said method comprising measuring a first current in a monitor line for a selected pair of said pixels while turning on both the drive transistors in the selected pair of pixels coupled to said monitor line and while the supply voltage of one of said two pixels is set to the voltage level at the node between said drive transistor and said OLED of said one pixel, measuring a second current in said monitor line for said selected pair of pixels while the drive transistor of said one of said two pixels is turned off so that the OLED in said one pixel is controlled by said monitor line, and determining a characteristic of the OLED in said one pixel, from the first and second measured currents.