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Samsung Galaxy SII SAMOLED display burn in - OLED screen persistence, retention S2

It is well known that the Samsung Galaxy S suffered screen burn-in on its AMOLED (Super Active-Matrix Organic Light-Emitting Diode) display. The most prominent area to suffer burn-in (or image retention) is the status bar. Early models with older firmware (e.g. Android 2.1) used a grey or white status bar, causing icons such as the clock and battery symbols to be clearly burnt in (and becomes very evident when the phone is showing a full-screen solid colour such as a grey background).

The Samsung Galaxy S II with its new Super-AMOLED display, released in early 2011, is yet to yield any reports on screen burn (as of August 2011) - but then again, it has been less than six months since its release. The Galaxy S has been around for about one year, and thus has had more opportunities for burn-in to occur.

The SGS2 runs Android 2.3, and by design, has dark menu bars and a black status bar. The darkness probably originated from the need to reduce power consumption on the Samsung/Google Nexus S, which also features an AMOLED display.

Ways to prevent / reduce screen burn-in

You can mitigate the possibilities for screen burn in by adhering to these simple rules:

• Always try to set the display as dark as practical. Running the display at full brightness will aggrevate the potential for burn in. Organic LEDs, especially the blue ones, tend to degrade in brightness more rapidly when display intensity is increased.
• Disable the auto-brightness. Quite often, an AMOLED display set to low brightness is more than bright enough for nearly all indoor environments, and there is little or no need to increase the brightness. When outdoors, you can easily increase the brightness on the SGS2 by holding and sliding on the status bar (which acts as a hidden display brightness slider). Just remember to slide it back to dim when you no longer need the added brightness.
• Set a shorter display time-out. A 30 second or 1 minute timeout is very effective at reducing the time the screen is 'on' when the phone is idle. Only set a longer time-out (such as 5 minutes) when you really need it, although such occasions should be rare.
• Use dark wallpapers. A solid black wallpaper is even more effective. The other upside to having dark wallpapers is that it saves battery power. Organic LED displays don't use a constant backlight (such as with LCDs), and will actually consume less energy when showing a dark image. If you must use a non-black or other artistic/photographic wallpaper, change them every once in a while so the same image isn't constantly being displayed.
• Try not to show static content. This applies especially to the home screens. Change or re-arrange your icons and widgets so nothing is ever constantly in the same place more more than a few weeks at a time.
• Try not to expose the screen to strong sunlight. Organic LEDs will break down and degrade rapidly when exposed to ultraviolet light. Fortunately, the glass covering on the phone stops most of the UV from direct sunlight, but the heat and light can still cause some degredation.
• Occasionally change the way icons appear on the status bar. This can be as simple as changing the clock format from 12-hour (AM/PM) to 24-hour. When in 12-hour format, the AM/PM symbols don't change much and pose a real risk to burn-in (particularly the 'A'). By switching to 24-hour format, the AM/PM symbols are not shown, and the digits of the clock actually get shifted to the right to take up the space originally occupied by the AM/PM. This has the side effect of shifting other icons that constantly show, such as the battery status. If you do this every month or so, it can be an effective way to prevent burn-in on the status bar area.
• Install the Screen Filter app. There is an application by that name on the Google Android App Market. Screen Filter allows you to further dim the screen below the minimum available setting via the normal means. It will also help to further reduce power consumption on (S)AMOLED screens. Dimming the screen can make it easier on your eyes when using the Galaxy S / SII at night, because even the normal minimum settings can still be blindingly bright. It can even dim the screen until it's completely black if you want, but they say if that happens accidentally, the app will need to be uninstalled (e.g. via Kies) to restore the brightness.

Diagnosing screen burn or image persistence

You can activate the diagnostics on the Galaxy S2 by keying in *#0*# into the dialler keypad. A menu will appear, and there are buttons to fill the entire display with red, green or blue. With a solid colour being displayed, you should be able to discern whether screen burn has taken place or not.

You can also create an image on your PC with a dark or solid grey colour. The image dimensions should be 480 x 800 pixels. Save it as a GIF or PNG and copy it to your phone, and display it using the gallery app. Using the same technique, you can create a solid black wallpaper to use on your home screen and/or lock screens.

Temporary image persistence

It has been noted that after displaying white text and certain icons for 30 seconds to a minute, then switching to a different image or menu, a very faint shadow imprint of the previous text/icons can be seen. This seems to be normal and the persistence will gradually go away after 20 to 30 seconds. It can be unsettling at first, but reassuring once the imprint dissapears.

SAMOLED display technology still in its infancy?

Commercially available organic LED displays have only been around for about half a decade, and high-resolution OLED smartphone displays for only a small number of years. Unlike LCD technology, which has had more than 20 years of perfection, organic LED displays still have a long way to go. The fact that they use 'organic' dyes and semiconducting materials means they have a limited lifespan. No one really knows just how long these displays will last. On the other hand, LCD displays manufactured 20 years ago are still going strong.

What can you do about it?

Unfortunately, not very much, apart from the points listed above. LED displays have a lifetime that specifies the time to half brightness (similar to the half-life of radioactivity). The light output will gradully become dimmer the more the display is used. So, things such as the clock and battery symbol will cause the areas of the screen they occupy to reduce in intensity, thereby leaving a sort of a darkened 'imprint' when the screen is showing a solid colour when the said icons are not displayed. Hopefully, the time to half brightness will be much longer than the useful lifespan of the phone itself. This may not please some purists and those who like to hold onto a handset for a long time, but is an unavoidable fact of this new display technology.

Unlike LCDs, OLED burn-in cannot be 'washed out' by displaying a complete white screen for an hour or two. A white image on an LCD causes the crystals to relax, thereby alliviating the problem of image retention when showing constant items such as desktop icons or status / task bars. But on an OLED screen, a white picture will cause more wear and degredation of the light emitting diodes.

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