Today’s Display Technologies Explained
Among the most important features of any mobile device is its display. The display is the one part of the device you will spend 99 percent of your time staring at when using it. But not only is it the main source of output, it’s the primary form of input, too. If the display is too big, too small or difficult to see in sunlight, using it becomes more of a chore than anything.
Like televisions, the overall quality of a display can be judged on a handful of specs – not just the size and resolution. Mobile displays are gauged on clarity, color gamut, saturation, contrast, reflectiveness, brightness, viewing angle and various other qualities. Also like televisions, there are a few different types of displays, and each excel or stumble in various categories.
Keep in mind, however, that not all of these categories are black and white. Often, these things are subjective. For example, Samsung’s HD Super AMOLED panels are notorious for supersaturation – colors are far from accurate, but the panel can make even the most dull images extremely vibrant and colorful. Some revel in the supersaturation, others prefer the more accurate colors of LCD panels.
In the search for a new phone, you might come across a handful of different marketing terms, such as PureMotion HD+, Retina Display or ColorBoost. But what do they all mean? Are they important? Should you care? Let’s break it down.
OLED stands for Organic Light-Emitting Diode, and this particular display type comes with its fair share of advantages and disadvantages. OLED panels have very high contrast ratios and supersaturation of colors. These are the two main reasons Samsung’s Super AMOLED (Active-Matrix Organic Light-Emitting Diode) panels are some of the most popular displays on the market. Blacks are very inky and colors pop.
The other notable advantage is power consumption. Unlike other display types, black pixels on an OLED panel are actually off – they have no power running to them – and save energy. Depending on the subpixel layout, though, OLED panels tend to have a blue hue. To be fair, most mobile displays err on the cool side. But OLED, especially Super AMOLED (non-PenTile), have a distinctly more blueish tint.
The problem with OLED panels, though, is lifespan. Blue pixels are the most inefficient subpixels in OLED panels; they draw more power and eventually end up dying sooner than the others. So that blueish hue tends to disappear over time.
If you enjoy an extra pop in colors and inky blacks, OLED (or Super AMOLED) panels are for you. You can find AMOLED displays in some Nokia, Samsung and Motorola smartphones, though more manufacturers are currently jumping on the Super LCD3 bandwagon for its accuracy and higher resolution.
ClearBlack and PureMotion HD+
One of Nokia’s staple terms in display marketing is ClearBlack. The basic function behind ClearBlack is to help the display perform better in direct sunlight, a sore point for practically every mobile display in existence (with the exception of Mirasol).
To fight the brightness of the sun and reflectiveness of the glass covering the display, Nokia gives its displays a few more nits of brightness and adds a couple polarizing layers to the display. Nokia compares ClearBlack to looking at a body of water in bright daylight. Because the light reflecting off the surface of the water, it’s nearly impossible to see beneath the surface. But if you throw on a pair of polarized sunglasses, you can see beneath the surface much more easily since the reflections are eliminated. The result is a display that’s easier to use in daylight (though still not perfect) without having to crank up the brightness and chew through battery life.
Nokia’s other display marketing term is one it introduced with the Lumia 920 in September last year, PureMotion HD+. It has a few tricks in its bag, such as extra fast responsiveness,
running at at WXGA resolution, low reflectiveness, higher luminance and contrast. Nokia also made its PureMotion HD+ display extra sensitive; it can be used with long fingernails or even thin gloves on.
Likely one of the terms you’ve heard more often than any other is Retina Display. is an IPS (In-Plane Switching) LCD display. The term, over time, has become a bit of a misnomer, though. Retina Display is not a display type in itself. Retina is a rating Apple made up, and it’s not an exact science, as it’s based on the display pixel density weighed against the average distance and angle the device will be used. There is some disagreement on what the exact rating of Retina should be, but it varies per distance and angle.
The term Retina is used to indicate the clarity of the display. When it was first introduced on the iPhone 4, it was easily the most dense display on a smartphone yet at 326 pixels per inch. The idea was that its density made it virtually impossible to distinguish individual pixels with the naked eye – that everything, especially text, would look crystal clear.
That said, the iPhone 5’s IPS LCD Retina Display is regarded by AnandTech as being one of the most accurate displays … ever, particularly in its price range. Chris Heinonen of AnandTech found that, by the numbers, the iPhone 5 display rivaled a $20,000 projector in color accuracy and grayscale out of the box. Impressive, to say the least.
True HD IPS+
LG’s recent display marketing term is known as True HD IPS+, and it’s found on the LG Optimus G and Nexus 4. LG boasts its True HD IPS+ display features true, natural colors, automatic color adjustments thanks to LG’s Mobile HD Graphic Engine, great brightness and power efficiency.
Some feel the display on some LG devices, such as the Nexus 4, is washed out, and it certainly looks so beside devices like the Galaxy Note II.
Recently, Motorola abandoned ship on Super AMOLED panels and decided to run with TFT LCD instead, and last year, it brought forward its own marketing buzzword, ColorBoost. Although it now uses LCD displays, the company fine-tuned its panels to match the saturation of OLED displays while maintaining the higher performance of LCD. It’s somewhere in the middle ground. If you prefer LCD but enjoy the saturation of OLED, Motorola’s ColorBoost LCD displays are likely your best option.
Another term that gets thrown around some is PenTile, but more often than not, this term is misunderstood. PenTile Matrix is not a type of display, it is simply a family of subpixel arrangements. Unlike the standard RGB pixel arrangement, which shares three subpixels to each pixel (one red, one green and one blue, PenTile Matrix shares subpixels and only requires two subpixels to each pixel. Red and blue pixels are staples while green pixels are shared between adjacent pixels.
The adversity to PenTile is due to noticeable grain in highly saturated images. For example, an image that has a large area of solid green may look like fabric. But there are various types of PenTile Matrix subpixels arrangements, and some offer advantages over others. For example, some formations incorporate a white pixel (RGBW), which allows backlight to come through, yielding a brighter picture overall with equal power consumption to a comparable RGB arrangement.