Dubai: The 4K or ultra high-definition (UHD) TVs are growing very fast, driven by strong demand and fall in prices, despite the scarcity of native 4K content.
The UHD TVs boast a pixel format of 3840 x 2160 resolution, four times that of the current 1920 x 1080p Full HD TVs.
Even though many of the brands are selling their boxes as 4K, some are really not 4Ks and it is only 3K. Some manufactures have increased the production of low-cost 4K TV sets to drive demand and make it less expensive to compete with Taiwanese panel makers in China, world’s largest TV market.
Linda Lin, senior analyst for large displays at research firm IHS, told Gulf News that the low-cost 4K TVs are really targeted at emerging markets, especially China, and it will not give a pure 4K resolution and will provide around three quarters of the 4K resolution (2880 x 2160), But they are counted as 4K TVs are far as shipments go.
She said that the panel makers add white pixels to cheaply create RGBW (Red, Green, Blue and White) panels with a high pixel density but low quality images.
The industry is disputing whether RGBW should qualify for the 4K standard. One group says it is not while other says it should be considered as 4K TV.
The RGBW panels were launched since manufacturers wanted to reduce a cost of 4K TVs.
China Household Electrical Appliances Association in 2014 has stated that there have been so-called “near 4K” TV on the market, the panel cannot reach a resolution 3840 × 2160, and thus sparked a debate within the industry.
The 3K TVs are less expensive and offers only three times more resolution than a Full HD. It is around 60 per cent less than the pure 4K panel prices and 25 per cent less definition and a duller colour spectrum as one of the RGB is missing in 75 per cent of the pixels.
Display industry professionals have pointed out that RGBW mode increases colour unevenness and the white is not a valid colour pixel, so, it will undoubtedly affect the performance of the panel colour purity and picture detail performance. Such a TV should be called ‘3K TV’.
The US and Europe adhere to strict UHD TV regulations but other countries like China, Southeast Asia and other regions do not have strict UHD regulations.
In bid to provide consumers with accurate product information, CEA and DE-IT organisations in the US and Europe have started a 4K UHD logo programme. Only TVs that meet the strict 4K definition and requirements are allowed to use a 4K UHD logo from CEA and DE on the package.
Paul O’Donovan, principal research analyst at Gartner, said that in a LCD TV, three colours — red, green and blue — sub pixels make one pixel but in a RGBW technology, four colours — red, green, blue and white sub pixels make one pixel. So, naturally the resolution will be lower as it cuts down on actual red, green and blue sub pixels.
Right now, the low-cost 4K TV will not create troubles as there is only a handful of 4K broadcasting. Once broadcasters launch 4K content across the globe, the images will be little blurred on a 3K TV.
The 4K broadcasters are offering 4K content in 50 frames per second compared to 25 frames per second since 1960s.
Mathew Mathai, Sony’s regional general manager for marketing and communications, told Gulf News, that the 4K (UHD) TV standard that is used for broadcast today is called UHD-1 phase 1 and operates at 3840 x 2160 resolution up to a maximum of 60 frames per second. As an example from Europe, BT Sport is using the 50 frame per second rate for their BT Sport UHD service.
“For the future, broadcasters are looking to UHD-1 phase 2 which will support 3840 x 2160 at up to 120 frames per second. But on-air systems operating at this rate are still some time off,” he said.
Industry experts and industry reports have said that Samsung Display, China’s BOE Technology and LG Display have developed RGBW UHD panels aimed at the Chinese TV market.
But Samsung claims to have stopped producing RGBW panels and uses only RGB technology for its own TVs while LG and some Chinese panel makers are still producing in China.
Paul Gray, principal analyst at IHS DisplaySearch, said that 4K is about offering a completely different video experience rather than just throwing more pixels at it. Ultra HD needs to be something completely different to conventional HD.
“You can use RGBW and get the same number of pixels and there is a way of doing it. You can get the same resolution in illuminance but not the same in colour by using a PentTile pixel layout. What we are seeing right now is a format war where there is a lot of briefing going on to change sides. It all depends on how you drive the panel as to what resolution you get in illuminance,” he said.
He said that LG Display is making panels with RBGW and Samsung is making RGB panels. This is like a kind of format battle between the Korean firms.
“The battle is on for how many pixels and how many sub pixels,” Gray said.
The disadvantage of RGBW, he said is that the colour saturation is “very slightly less” than RGB, which is unacceptable by some companies.
He said that Samsung is trying to confuse things by saying that resolution is lower and, at the same time, they are using diamond PenTile matrix structures in their AMOLED (active-matrix organic light-emitting diode) smartphones.
In the RGB stripe display, the sub pixels are of uniform size and order, providing accurate colours and a very sharp picture.
In the PenTile screen technology, some sub pixels are bigger and have fewer sub-pixels overall than RGB structure. It is favoured for several reasons, but primarily for two — it consumer less power compared to RGB stripe displays and achieves higher resolution due to the combined effect of increased aperture ratio and improved light transmission through the white (clear) subpixel.
The Korean giants are feeling the pressure as Chinese and Taiwanese manufacturers have ramped up production of cheap 4K panels.
“It’s true that Samsung applied the PenTile method on its AMOLED smartphones, but mobile device panel is completely different from a TV panel in terms of usage, size and so on. Additionally TV display standard is distinctly defined by 1:1 pixel aspect ratio, but mobile standard defines various formats,” said Vinod Nair, general manager of Samsung Gulf Electronics’ CTV Business.
He said in the TV format, the pixel aspect ratio should be 1:1 and it holds true for RGB panel while the aspect ratio in RGBW is 1.33:1.
According to the ITU (International Telecommunication Union), UN-affiliated organisation, ITU-R BT/2020 defined that pixel structure should be 1:1 square pixels for pixel aspect ratio and more than 3,840 pixels.
Therefore, Vinod said that RGBW is not 4K but only 3K, since it has “1.33:1” pixel aspect ratio and 2,880 x 2,160 pixels.
“We have RGB pixels and not RGBW,” he said.
In pseudo UHD, Nair said that they are arranged as RGBW and then they switch it around. What happens is that the size of the white cells is increased.
The 4K TV has 8.3 million RGB pixels (3840 x 2160) while a Full HD has 2.1 million pixels. For pseudo UHD (3K), you get only 6.2 million pixels instead of 8.3 million.
“We might look into it to fight the pseudo UHD vendors. It is not going to work in the future when UHD standard is finalised. It is more or less getting standardised and the frequency of 120 GHz is expected to be standardised by broadcasters,” he said.
Vinod said that all of its 2015 UHD TV models, encompassing Series 9 to Series 6 models, qualify for, and will display, the “4K Ultra HD” logos developed by the US Consumer Electronics Association (CEA).
“The CEA logos are only eligible to be used on UHD TVs that satisfy the ‘level of picture quality’ defined by the CEA. This definition distinguishes true 4K UHD TV models from other models employing RGBW pixel structure,” he said.
“Consumers are also being deceived by low prices. In tests run by German association Verband Deutscher Elektrotrchniker (VDE), low-priced UHD TVs did not meet the definition of UHD,” he said.
LG is using the RGBW as well as RGB technologies on its TVs but J.D. Lee, general manager of TV department at LG Electronics Gulf, said that adding ‘White’ to the sub-pixel rendering technology does not reduce the pixel count while the TV becomes brighter and consumes less power.
“RGBW technology is cleared by many external technical institutes like Intertek (UK), TUV (Germany), UL (US), CESI (China), and JEITA (Japan) and it gives 8.3 million pixels,” Lee claims.
Brian Chen, senior industry analyst with Taipei-based Market Intelligence & Consulting Institute, said that LG Display’s RGBW panels provide true 4K resolution. And aside from shipping to the Chinese market, LG Display has been selling RGBW panels to other markets but DE and CEA haven’t approved 3K as UHD and 3K TVs embracing RGBW panels cannot be sold in the United States and Eurozone.
LG also said its RGBW structure allows for the same colour reproducibility as a RGB structure, as well as the same picture quality as RGB UHD when upscaling from Full HD to 4K.
According to Sigmaintell Consulting, LG has been focusing mainly on production and sales of 49 and 55 inch 4K TVs with RGBW technology. This technology has accounted for 28 per cent of the shipments of 4K TV panels in the second quarter and this percentage is expected to grow to 35 per cent for the whole year of 2015, largely due to demand from Chinese sellers like Konka, Skyworth, Changhong and LG Electronics itself.
“Sony does not make TVs using the sub-pixels RGBW method. We are designing 4K TVs which are complaint with the TV broadcasting regulations in each region. Almost all regulations specify the screen resolution at 3840 x 2160 pixels. So we have not used sub-pixel rendering technology that can realise apparent 4K resolution with less pixels,” Mathew Mathai, Sony’s regional general manager for marketing and communications, told Gulf News.
Anthony Peter, director of corporate communications and operations division at Panasonic Marketing Middle East & Africa FZE, said that Panasonic does not produce 3K TVs and adheres to industry spec 3840 x 2160 pixels for its 4K TV technology.
Lin said the RGBW sub-pixel technology is now widely accepted in the Chinese TV market and has even begun to penetrate the global market.
Sharp has added a yellow sub-pixel technology to its Quattron Pro TVs to enhance yellow and green colours. It is a Full HD TV but Sharp had divided the subpixels to double the number of addressable subpixels by giving a ‘near UHD’ TV resolution.
Industry experts said that a magnifying glass or a smartphone camera can be used to check the white pixels between the RGB colour pixels in the pictures.
