Darkness level and contrast:
As we know, contrast is the difference between the darkest part of a picture and the brightest part. If a display delivers a truly black dark portion, it does not have to make the bright parts quite as bright to achieve good levels of contrast. In this term, OLED is best because it has ability to generate completely black or dark when it needs to. On the other side, QLED contrast is forced to dim their LED backlights and block the remaining light, which is not much perfect. From this viewpoint, OLED is the winner.
This decision is going to QLED, you will find the reason soon. QLEDs have good brightness because they use separate backlights instead of creating their own light. These backlight LEDs can be made very bright. On the other side, OLED panels are not able to compete on a pure brightness basis. Their individual light-emitting pixels simply cannot produce the same amount of light. In the darkroom, brightness was not an issue but in daylight, room brightness becomes a considerable property.
Response time refers to the time it takes for a pixel to switch from one state to another (means color change). The less response time creates crisper picture quality, especially in moving picture technology. Though human eyes cannot differentiate the response time of QLED and OLED. Typically QLED provides 2 to 8 milliseconds response time which seems to be good but waits it is not better than OLED. OLED response time is approx 0.1 milliseconds, which is much better than QLED. In the matter of response time, OLEDs are fast.
OLED display screens, by comparison, can be viewed with no luminance degradation even at drastic viewing angles – up to 80 degrees. Some QLED displays have improved their viewing angles with anti-reflective layers, but there is no comparison with OLED.
OLEDs have come with a long process and it becomes costly whereas QLED technology is easier and less expensive to produce at larger sizes.