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MD4 Screen burn-in time without screensaver

David Parkinson 5 years ago in Master modules / MD4 updated by Gustav Widén (System support) 4 years ago 5

How long does a static image need to remain displayed on an MD4-7 screen before image burn-in is noticeable?

Assume worst case. (Worst case being probably full brightness with high contrast graphics??)

What is the recommended time-out for when a screensaver should start? Would just dimming it for the screensaver avoid burn-in? How much should it be dimmed?


The MD4 instruction book (rev 2015-12-02) says:

Burn-in

The IQAN-MD4 TFT display, like other computer screens can have a ghost picture

occur if a static image is left on the display for extended periods of time. For the best

viewing over the life of the product we recommend using the screensaver functionality.

NOTICE

To avoid burn-in, use the screensaver on the display

GOOD, I'M SATISFIED

Thanks for digging further into it, providing a work-around, and an expected path forward for IQAN.

Satisfaction mark by David Parkinson 4 years ago
+1
Answered

I did some reading, and also checked what the component supplier of the LCD has to say.

In the documentation for the LCD we use in the IQAN-MD4, there is the statement:

"The use of screen saver or sleep mode is recommended when static images are likely for long periods of time. This is to avoid the possibility of image sticking."


But there is no specific limit on how long an image can stay on before this effect is noticeable.

As this is a possibility for any LCD display, it is interesting to also read this article about the phenomena:

https://en.wikipedia.org/wiki/Image_persistence


One interesting point here is that in the wiki article, the term "burn-in" is used for the permanent problem old CRT type displays, while "image persistence" is the word used for the temporary effect that can happen on LCD displays (like the MD4 or MD3).



For the IQAN-MD4, the default option in the display preferences menu is to just dim the backlight. As this does not switch to a different image, this would most probably not have any effect on the possibility of getting image persistance on the MD4 (or MD3).

Thanks so much!


The conclusions I draw from this are as follows:

  • The risk of damage is less than I thought: a “ghost image” (or “image persistence”) should go away if left un-powered for several hours or days. It doesn’t look like “image persistence” would be permanent.
  • There is no use in using the built-in screensaver options: Dim or going to black won’t prevent “image persistence”.
  • If we want to prevent “image persistence”, we’d need some other screen saver that either goes
    • All white screen: not really what a user would like probably
    • Or a constantly changing image: maybe displaying the important information/gauges moving around the screen or something. Is the MD4/IQAN capable of displaying a screensaver like this?
  • Parker should change the wording in the manual to not use the term "burn-in" and also point out that the "image persistence" is temporary.
  • There should be some other built-in screensaver options in IQAN that would prevent "image persistence".

Thoughts? Agree/Disagree?

+1

Attached is an example of how to make an automatic display page switching:

Automatic switch page.ids4


It runs a timer that is automatically resetting itself at a fixed interval, every time it reaches its maximum value, an IDC is activated. This is connected to the "Show" property on a separate display page.

On that display page, I a button that covers the entire screen area, the action of this button is to close the page.

On this page, I have placed some smaller images that switch on and off, controlled from the same timer.


I agree that it would be good to have one of the built-in screen saver option for the MD4 designed so that using it minimize the risk of image persistence. On the MDL, MDL2 and MD3, the screen saver option "black" switches to a black image. On the MDL, MDL2 and the MD3 versions predating the MD3-M15 this was necessary to make the screen completely black, as the LCD:s used on those modules were transflective. On the MD4, bringing it to 0% backlight already makes the screen completely black without changing the image, but we could probably change that.


For the question How long would it take for image persistence to show up?, I am sorry to say we don't know. The LCD component supplier do not specify this, they only state that it is a possibility. What I am quite sure of is that the majority of IQAN users are just dimming the backlight, and I have never heard of any reports of image persistance on MDL/MDL2 or MD3 over the years. But then most applications have at least a couple of hours every day or week when the machine is switched off, so that may be why we have never heard of it.


We are updating the IQAN-MD4 instruction book.