‘Is white (W) pixel that is applied in UHD LCD Panel a valid pixel or no?’

With a meeting to revise international standards of measuring display’s resolution in place soon, Samsung Electronics and LG Display are arguing against each other with this problem. Because if W pixel is not seen as a valid pixel, number of sub-pixels will decrease as well and it will not be categorized as UHD Display.

Source of controversy started when LG Display put out ‘M+’ Panel that uses new RGBW method. M+ is 4K UHD Panel with relatively inexpensive price and 30%-reduced electricity consumption. By applying this product into inexpensive UHD TVs, LG Display has been receiving positive responses from China and others and is expanding it towards middle-level products. As LG Electronics’ products were receiving favoritism, Samsung Electronics’ Video Display Business Department brought up a problem with LG Electronics and LG Display by saying that RGBW Panel is actually not 4K resolution, but only 3K.

Samsung also proposed revision of measurement standards of TV resolution to International Committee for Display Metrology (ICDM) under Society for Information Display (SID). If new standards are introduced, there is a higher chance that RGBW method will not be considered as 4K resolution.

◇Samsung Electronics proclaims that W is not a valid pixel.

Samsung Electronics’ Video Display Business Department, which is in charge of TV business, is voicing its opinion that W pixel is only used to increase brightness and is not a valid pixel that expresses official color.

RGBW method that is commercialized by LG Display adds W sub-pixel and forms pixels in an order of RGB-WRG-BWR-GBW. Samsung is saying that because there are not 3 one kind of colors out of 4 sub-pixels, its color expressiveness is only 75% of current RGB structure and falls short of actual UHD quality.

Samsung Electronics is saying that it does not have to do with technology method, but rather a problem lies on a fact that W cannot be seen as a valid sub-pixel. It is pretty much saying that W pixel does not make color any richer.

It is also criticizing that it is a significant problem that it does not meet ICDM’s defined standards that sub-pixels need to express their own colors.

Samsung Electronics also mentioned that a fact that LG Display’s UHD Panel only received ‘validation’ instead of ‘certificate’ from European standard certificate organization called TUV Rheinland. Instead of receiving an official certificate after going through a screening according to standards, it only received verification by requesting ‘service’ whether or not this new method can be used.

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<Display’s UHD technology ‘M+’ that uses RGBW pixel (Picture = LG Display’s blog)>

◇LGD refutes that if lack of number of pixels is a problem, then all of Samsung’s IT products are fake

LG Display is fully refuting Samsung Electronics’ Video Display Business Department’s opinion that only RGB method, which puts 3 elements of R (red), G (green), and B (blue) into one pixel, is truly UHD resolution.

LG Display is saying that if Samsung’s opinion about how putting all of RGB into a pixel can express true quality, then Samsung Electronics has been applying fake panels all along since Pentile method for Samsung’s Smartphones, certain tablets, and laptops and Diamond Pentile method actually have lesser resolution than RGB method.

Traditionally display technology has 3 sub-pixels of RGB express all of colors and make one pixel. Pentile method, which is in order of RG-BG-RG-BG, has 2 sub-pixels express one pixel.

Pentile method’s number of sub-pixels is two-thirds of RGB method and it cannot wholly express color and brightness compared to RGB method.

Ultimately LG Display is saying that if Samsung Electronics proclaims that RGBW method’s quality is low since it has lesser sub-pixels than current RGB method, then what Samsung has been advertising about its resolution is actually not true since Pentile method has lesser quality since it has lesser number of sub-pixels.

While Samsung Electronics had been using panels with Pentile method for Galaxy S and Galaxy Note, it eventually changed to RGB method for Galaxy S2 and Galaxy Note 2 when there was controversy about Pentile method. Afterwards it introduced Diamond Pixel Pentile technology, which places pixels in a diamond form rather than in a straight line so that it can express curved lines even more smoothly, for Galaxy Note 3. Afterwards Samsung Electronics has been using Pentile method for Galaxy Note Edge, Galaxy S6, tablets, and part of ATIV models.

RGBW is a new technology that solved traditional display problems such as heat, efficiency of electricity and others and it is a new technology that had been developed by universities and industries for more than 10 years. Its strength is that it is more advantageous than traditional RGB method in low electricity and brightness.

LG Display is saying that since overall brightness is not so good when pixels are finely arranged in small area due to UHD’s characteristic, it expressed UHD resolution by adding separate W pixel. It is saying that W is actually a valid pixel since it is placed as a formal pixel rather than a backlight.

“RGBW is a new technology that took a major step forward from a traditional display technology.” said an employee from LG Electronics. “Markets are able to grow when there are new technologies, but our competitor is rather blocking development of technologies.”

On a separate note, RGBW Panels have been receiving positive responses from China, Europe and others in this year. It seems that there will be more new panel competitors that choose RGBW method. Market research company HIS is predicting that about 22% of shipments of UHD panels next year will be based on RGBW method.

Staff Reporter Bae, Okjin | withok@etnews.com