Image retention (also called burn-in when it is permanent) happens when an image gets imprinted on screen after being displayed for a long period. Once the image retention occurs, you will notice it after a change of content or input. After a change of content, the imprinted image will appear as a faint remnant, visible through the new content. As an example, this is most obvious when elements from a video game such as life meters are still visible on top of a TV show after playing a video game for a long period. This is really more an issue for people playing video games, using their TV as a PC monitor, or watching sports and 24 hour news channels due to static banners or logos.
When testing for image retention we take photos at predetermine times, to analyze the amount of the original image that get retained after being displayed for a specific time.
When it matters
The image retention test is relevant when some parts of the screen are static, like when playing video games, using the TV as a PC monitor or using the TV as a display during an office meeting. It is also important when watching long sporting events or news coverage due to static graphics. It tends not to be a problem for people who only watch normal TV shows or movies, since in those cases it is very rare to have static image displayed on the screen for a long amount of time.
It takes a while of displaying a static image before image retention begins to be visible, so depending on your use it may not be noticeable. This is why it is usually going to be gamers or PC users who experience it the most as they often have parts of the screen that are static, like a progress bar or the start menu from a PC. While the static image is being displayed the retention won't be visible, as it is only when changing content such as watching a movie that the image retention is going to be noticed.
Image retention test video
Our image retention test video is made to test the resistance of the TV panel to image retention. It is made up of 3 different specific scenes:
- 15% gray scene: These scenes are used as a pause to take the test pictures needed to analyze the image retention. There are 7 pictures in total, the first one is the reference picture taken before the 10 minute burn-in scene and 6 more, taken at 2 minutes interval to document the recovery. The 15% gray makes any retention as visible as possible. On other colors or saturation the retention is usually less visible.
- 10 minutes burn-in scene: This is the scene that really tests the TVs which are prone to image retention. It tests specific colors and backgrounds to make it most obvious which are most effected. Note that a moving white square is used on each side to try to mitigate the dimming that some TVs apply when there is a static image for a long period.
- RGB recovery scene: This is made up a 3 full screen red, green and blue alternating images, and is intended to get each of the 3 sub colored pixels to return to their usual performance.
To evaluate the image retention and stay consistent across all TVs, we adjust the backlight on the 15% gray scene to 2 cd/m², with the TV at calibration settings and with any local dimming features disabled. We play the video and take pictures of each 15% gray scene.
IR after x min recovery
To determine the amount of image retention, we compare our reference image taken before the static logos with pictures taken after the 10 minute burn-in scene. These recovery photos are taken at 2 minute intervals, to provide an idea of the amount of image retention over time. We can then determine how much image retention is left.
TVs which continue to display image retention after a longer period of time (such as 10 minutes) generally present more of an issue, as the retention continues throughout normal content. This is worse than a TV which recovers quickly.
- Contrast: Maxing out the 'Contrast' setting will generally increase the risk of image retention and burn-in on both LCD and OLED TVs.
- OLED Light: The brigher you set the luminosity of the screen on an OLED TV, the more image retention there will be.
Not all TVs suffer from image retention. Here is the information about the different type of TVs:
- IPS TVs: IPS TVs are the most common type of TV that suffer from image retention. Not all IPS TVs have the same degree of image retention though. See our table above for comparisons.
- VA TVs: VA TVs are practically all free of image retention. During our testing, none showed up image retention and none were even noticed in our everyday work.
- OLED TVs: OLED TVs are another type of TV that suffer from temporary image retention. OLED image retention does not look the same as that seen on IPS TVs, since the display technology is not the same. Unlike IPS TVs, OLED TVs come with a special function in the TV operating system specially aimed at getting rid of more durable image retention.
In any case, whatever the type of TV, image retention is not a permanent problem but more a temporary annoyance.