The final speaker in a long day was Don Gyou Lee of LG Display who talked about future technology challenges in new displays and the issues of metrology of these innovations. He works in transparent displays and also VR. He is involved with ICDM, the IEC and ISO.
There are new products such as flexible displays and it’s not clear how to measure these. HDR is a big topic, but is undefined. He said that the best way is to look at the level of HDR coverage. For example, you could deliver a metric based on the percentage coverage of the ST.2084 range.
In VR and AR, there are two big metrics – latency (including whole system and display) and the ‘screen door effect’. He is also trying to find a metric for the screen door effect that can be very visible when there are optics to show the display.
Lee is also looking at transparent display. One factor that is often measured is transparency, but another is haze. If you use a transparent display close to a real object, then there is no problem, but if the object is in the distance, the pixel causes a diffraction effect (which makes a transparent display unusable in a car window, for example). This is why transparent displays are only used for close objects such as fridges. The use of different LC materials, such as TN vs VA vs IPS, also makes a difference. He has a proposal for a measurement of the diffraction effect and he will propose it to the ICDM as he has already proposed it to the IEC.
He has tested the metric and it seems to match the subjective result.
Hmmm, the comment about diffraction looks like a ‘guilty little secret’ for transparent displays based on pixelated displays. (BR)