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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