I've bought a used Waveshare IPS LCD and it has a ghosting issue, were as if you turn it on after about 30 seconds it starts to have ghosting and also burning on the edges effects, I am 90% sure that there is a problem with the LCD panel not the Driver board. Diagnosis steps that I've done:

  1. Turning on the LCD and driver board at the same time: It behaved as I described

  2. Turning on the driver board for 5min then connecting the LCD panel: things started to appear after connecting the panel

  3. Turning on the LCD and driver board at the same time while LCD back-light is off the turning the back-light on after 5min: It was already ghosting and wasn't related to back-light

  4. After being turned on for a while I had to keep it off for hours to all the ghosting get removed

  5. Different back-light levels didn't made a difference

  6. Different ambient temperatures didn't made a difference

I'm not an electrical engineer but as I researched I thought it might be a problem from a PCB part like capacitors, also if I leave it on for more than 20min it starts to flicker and the Faraday coil on the PCB starts to make noise. You can see the display model and the condition and also the PCBs below (sorry in advance for the image quality, didn't had a better camera):

enter image description here enter image description here https://mega.nz/#!TVFAjQ5Q!cSdygakuAvUJBQfzu2favwnQ_lEb7XdRMcdfsXHNJYQ https://mega.nz/#!SBNSQapC!YSgl0yqac-tyU5eqvx9nIODA84SO47L-URM6HgNCXCI https://mega.nz/#!LNM0HCoT!P2OCXkQDQckWi1lpIV3kp-2x_GTM1cEUVvoC9BdiFN

I can give you voltage read outs on the LCD panel's PCB pins if needed.

The other problem I have is with a Sony Z Ultra display panel. It has ghosting issue too, but it is not permanent and it is temperature sensitive:

  1. Being in a ambient hotter than 18c starts the ghosting and small amount of flickering
  2. Tried to eliminate all the parameter that could make noise on the signal by electrical taping over the display's flex cable parts, placing the battery distant from the flex cable and removing all the antenna parts near it and also spacing between the touch and display panel

  3. The issue happens more when LCD's back-light is on lower values

  4. Only 1/4 bottom part of the display has this issue and also it happens more when the display tries to refresh the image. Some time there are some black lines between the problematic part and healthy part

  5. After using it for a month or two the problem got to all the display but bottom parts the issue was more intense
  6. After being turned off for 6 months then turning it on I had no issue, then after a day of use, it got to the 1/3 bottom part

  7. The phone's display had been broken and been replaced with a used one then the issues started to show up

You can see the images below: enter image description here enter image description here https://mega.nz/#!zUd0WIZB!CLLIk1Ggb2nchPBoORpwLGKn2XXDyu2fXkCncHlbGBY

As both display panel were bought as used condition, I don't know the original cause and time of occurring this issues. If your solution is to buy a new one, I am aware of that. But I want to find out the reason and learn new things and if possible fix the problem and thinker with it. Thanks for your help and patience.

  • \$\begingroup\$ Ghosting, if lateral, can result from adjacent pixel-drivers interacting. Consider improving various bypass capacitors. Is the ghosting at bright regions, or in dark regions? There may be tap-drivers to shape the GAMMA curve, and the tap-driver opamps are mis-behaving. \$\endgroup\$ – analogsystemsrf Jul 18 '19 at 2:57
  • \$\begingroup\$ Thanks for your response. In the Z Ultra ghosting is more noticeable when in bright images but it happens in dark ones too. It mainly occurs in 1/3 of the display from bottom, although last year it grow more as I used it for a month. The Waveshare ghosting happens every where and it starts too black out from the edges. How can I improve the bypass capacitors? As in Waveshare one there is a changeable resistor, as I turned it the burning gets inverted in terms of brightness or darkness not color... @analogsystemsrf \$\endgroup\$ – Mohammadreza Souzandeh Jul 18 '19 at 3:12

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