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Why 8K TV is Going to Develop

I’ve already been at IFA a couple of days as the show opens to the public today. I have been in the Samsung Innovation room where the firm and a number of independent specialists have been talking about developments. There were six topics covered and today I’ll cover one of them – the one that I presented.

I was the first speaker in the session and covered the development of 8K TVs. There has been some negativity about 8K since some comments by Omdia at NAB a couple of months ago and I know that my good friend, Paul Gray of Omdia has quite negative views on 8K. I understand his reasoning, but I disagree as I think he is looking mainly from one perspective.

Author pose procThe author in a characteristic pose! Image: courtesy Samsung Electronics

I often get the impression from people in and out of the display industry that they think that somehow 20/20 vision is ‘perfect’. The phrase is often used in general speech as meaning perfect sight, but, at best, it means average visual acuity – the 20/20 means that the person can see at 20′ what an average person sees at 20′. However, many people, not just fighter pilots, and many young people can see down to 20/10 vision. And testing vision with a standard eye chart does not take into account issues such as vernier acuity – the ability of humans to notice when two lines don’t meet. We have way better acuity on this kind of measure.

The work behind the decision to develop 8K was partly based on work by Dr Masaoka of NHK who undertook some really, really good scientific work to try to understand what resolution you need for people to be unable to distinguish the dotty images on their screens from reality. He set up elaborate and carefully controlled tests that presented research subjects with a real object and an image of that same subject. He found that almost everyone, was able to detect the real object from the image up to around 60 cycles per degree (CPD). CPD is a really good way of understanding acuity as it takes the measurement away from particular display sizes or viewing distances. It’s as useful on a big LED as it is on a TV or a notebook.

60 cpd is approximately the same as 20/10 vision. Masaoka found that above that level of resolution the number of subjects who could differentiate the real from the image fell away quite fast, although some could still see the difference at >150 cpd!

TV Size and Viewing Distance

Now, high resolution TVs are designed and intended to be used at closer viewing distances than traditional standard definition because occupying more of the visual field gives a more immersive experience. NHK also studied that. The recommendation is that the viewer should be 1.5 times the height of the display away from the set. That’s a bit closer than has been typical in the past, but I think that the increasing trend to gaming on TVs via the cloud or using consoles will encourage more people to sit closer to the set.

The size of TVs has also been growing and is likely to continue to grow. Here is the DSCC forecast for TV sizes, presented at the DSCC/SID Business Conference this year. It shows a continuing trend.

TV size

However, another factor is going to be the challenges with oversupply in the TV LCD business. At the moment, there is a huge surplus in TV panel production and panel prices are at an all time low. The TV market is not going to grow very much in the next few years, so the only way that the panel makers can get the market to absorb more glass is to promote larger sets. 75″ panel costs have been higher (per sq, metre of glass) but DSCC recently reported (registration required) that the premium has now gone. We may seen even cheaper prices for bigger panels in the future.

CPD is a function of viewing distance and increasingly, TVs are being used for cloud and console gaming. Gaming is a ‘lean-in’ experience so gamers like to be closer to the screen. If you are close to a big screen you see the pixels and 8K can make a big difference. Watching Netflix or a film is much more of a ‘lean back’ experience.

Display Industry Dynamics

Most of the TV panel industry is based on LCD and the industry is going to basically stay that way for some time. There is a premium segment for OLED TVs (WOLED or QD-OLED), but the investment to build the fabs for this segment has been more than $10 billion. The industry is not going to invest in a lot of fabs for big OLEDs when the investment is so high, the technical risk is high and the market for TVs is not growing.

Panel DemandPanel Demand for TV – Source: DSCC – DSCC/SID Business Conference

LCD makers know that making OLEDs is very difficult. First, as OLEDs are current driven, you need more than one transistor per subpixel (which you use for LCD) – typically three to five. That massively complicates the manufacture of OLED panels and with the increase in subpixels for 8K, makes a big difference in the ease of manufacture. Further, all the energy has to pass through the transistors and that means that the mobility of the silicon has to be higher. So, 8K OLEDs are really tough to make which is why LG Display only has one 8K panel and the sets using it are very expensive. It’s also why, I think, SDC only makes 4K QD-OLEDs at the moment.

For the LCD makers, as David Barnes used to say ‘Pixels are free’ (8K is Closer than You Think). The LCD business, he used to say, looks to an economist like a material resale business – with low margins over the cost of the materials. Making an 8K panel uses the same amount of glass, polariser, liquid crystal and metalwork. The filter is a bit more detailed, but not much more. With 8K the drivers cost more (although Hyphy thinks it has a solution to that (HYPHY Eases Pain Points for 8K Displays) and you are likely to get lower yield with the more complex backplane and you need more backlighting. So the LCD makers can make 8K panels where they know the OLED makers will struggle. That alone will provide impetus in the supply chain.

Content – Delivery – Display

If we look again to the enablers, for any display system you need content, you have to deliver it and then you have to display it. There has been much talk of ‘there’s no 8K content’ – but that is a classic chicken and egg situation and I remember the same point being made when FullHD and UltraHD were launched. There is 8K content being created – the tools, including cameras, and workflows are developing. But it will take time to get a lot of native 8K content.

In terms of delivery – better codecs are being developed and you can already deliver good 8K at 50 Mbps. 8K content is going to be distributed by streaming. Broadcasters are not going to do much – even satellite broadcasters, who do not have spectrum issues to deal with, are still mostly transmitting SD channels, with less than half in HD and with only a handful of 4K (Eutelsat Organises a Webinar on UHD). Blu-ray or other packaged media is not going to be developed for 8K. The cinema industry, it can be argued, is in an existential crisis, so will not develop 8K (DCI only currently goes up to 4K as far as I am aware).

But streamers will deliver content and it can be delivered directly to the set as Prime video and Samsung are demonstrating (Samsung Electronics and Prime Video Bring ‘The Lord of the Rings: The Rings of Power’ to Life in 8K). Prime joined the 8KAssociation last December (8K Association Announces Certified 8K TV Specification Update & New Members Including Prime Video).

Faster broadband is coming – I have a Gigabit at home now – 50Mbit streams are not a challenge. Not everybody has this yet, but many will in the future.

Disrupting the Chicken & Egg Challenge

One of the big differences between the development of HD and UltraHD and the growth of 8K is that in the last few years, upscaling has really developed very dramatically. Given the best AI-based upscaling and good quality 4K content, I don’t think that I could tell if I was watching upscaled 4K or native 8K unless I had a side by side comparison (although image quality experts might!). That means that if you have a big TV and you are close enough to it to get an immersive experience, you can use an 8K set with upscaled 4K content and still get a better experience than with a 4K set.

That is especially true with gaming and it might be argued that the best way to get a 4K 120Hz gaming experience with a TV might be to use an 8K TV – as long as it has HDMI 2.1 with VRR support.

The Best Sets

Finally, 8K resolution is only one factor. The ISF teaches that contrast, colour and detail are the key attributes of a great image. However, 8K sets are likely to be the ‘top of the line’ sets, so the 8K panel is unlikely to be put on a poor platform. 8K panels are typically combined with other important image quality features such as miniLEDs, Quantum Dot colour and the best processors and audio. That should make an 8K set a good choice! (BR)

Thanks to HYPHY for moving this article outside the paywall on Display Daily. It does not get counted as one of your two free articles per month if you are not a paying subscriber.