Measuring OLED displays in production environments

Measuring OLED displays in production environments

Displays are being integrated in more devices than ever. Nowadays displays are used in cars, phones, tablets, laptops, watches, household appliances, etc.

LCD has been the dominant display technology for many years, during which the technology matured and reached its limits with respect to resolution, brightness, contrast, color saturation and speed. There have been multiple display technologies aiming to replace LCD of which only a few seem capable to actually challenge it. And now, nearing the end of this decade, OLED technology is on its way to push LCD aside.

Major mobile phone and tablet manufacturers are already using OLED displays in their top-tier product lines because of their superior contrast and color saturation. These properties give manufacturers a competitive advantage, but they also create challenges when measuring these displays in their existing measurement systems. These measurements need to be done to accurately calibrate every display, so color performance is constant for each device.

Need for highly sensitive and accurate colorimeters

The colorimeters used for LCD technology performed very well for many years in mass production environments.

However, when re-using these systems for OLED display technology they will be relatively slow. The internal sensors need a minimum amount of light for accurate measurements, and the deep OLED black levels offer less light to measure. This will result in longer measurement times during which more light is collected to compensate. Sensor technology and electronics will need to improve so measurement time can be shortened for measuring the black level of OLED displays.

Furthermore, re-used systems may be less accurate on OLED displays as well because the emitted light has other spectral characteristics than LCD. Within the colorimeter, the transmissive filters which create the XYZ tristimulus functions have spectral imperfections and will need to improve so the color measurement will be more accurate.

To optimise tact times while still maintaining high measurement accuracy in mass production environments the OLED display and device manufacturers need more sensitive and more accurate measurement equipment.

Article Source : https://www.admesy.com/zh/articles/measuring-oled-displays-in-production-environments/