Measuring and Correcting MicroLED Display Uniformity

Methods to Measure Subpixel Luminance and Chromaticity for Correction (Demura) and Quality Control

MicroLEDs continue to demonstrate performance advantages for displays, ushering in a new generation of backlit and direct-view illumination technology. These inorganic emissive elements offer many benefits over other display technologies including high brightness and contrast, wide color gamut, longevity, and high pixel density. However, challenges associated with fabricating high-quality microLED panels must be addressed before viable mass production and commercialization can be achieved.

As individual emissive elements, microLEDs commonly exhibit luminance and color variations at the pixel level. These variations require each microLED to be measured and adjusted individually to ensure visual uniformity across the display. Thus, a measurement and correction system for microLED manufacture must be capable of precise quantification of the output of each emissive element (the individual LED or subpixel), with very low takt times to correct the high quantity of emitters in a single display and to support low-waste, high-volume production processes.