Samsung Display XCR

The convention in the past 100 years of colorimetry has been to solely measure the response of the achromatic visual pathway when discussing brightness and human visual sensitivity. – Samsung Display

“Samsung Display argues that ‘perceived brightness’ should be used rather than ‘luminance’ due to how our eyes and brain work. Samsung Display’s XCR measurement method has now been officially implemented by SEMI (Semiconductor Equipment and Materials Institute), an institute representing over 2,500 semiconductor and display companies around the world. SEMI is responsible for reviewing and establishing international standards. According to Samsung Display, XCR was “almost twice as accurate as mean luminance in predicting which one of two HDR displays observers would find brighter for a variety of HDR images.”

“Even when two screens have the same luminance value, the human eye will still be able to see a clear difference in perceived brightness. This is because human perception of brightness is affected not only by luminance, but also by the type of color and its saturation.” – Samsung Display. This phenomenon is known as the Helmholtz-Kohlrausch (H-K) effect.

Source: flatpanelshd

While not disputing that more saturated colors appear brighter, in their review of the Panasonic MZ2000, the Italian tech website DDay.it says that the superior color volume coverage of QD OLED is more a theoretical than practical advantage, writing:

“As we have already seen with the test of the new LG G3 always with new MLA panel, the greatest contribution in image brilliance is always made mainly by the white subpixel, which results in a reduction in color volume on high lights compared to RGB displays. It therefore increases the peak luminance, which is certainly positive, but not the overall color volume (as with the LG G3 around 70% of the DCI-P3 space compared to an ideal screen of equal peak luminance measured on the CIELAB space), which therefore continues to be lower than screens based on mini LED or QD-OLED technology. As we always emphasize when it comes to color volume, it is a more theoretical than practical “inferiority”, since then with real content the differences are only noticeable in infrequent situations and with marginal results.”