Comet lines inside LCD panel - Page 1
Forum section: electronics / repair

author: sdancer75
author_rank: Frequent Contributor
timestamp: January 22, 2023, 11:03:01 pm
content: This is LG 49UH850v European model which is an alias for the 49UH8500 American model.The TV displayed some irregular white spots. This model has edge led strips. Can someone explain what are these white marks?

author: AndyBeez
author_rank: Frequent Contributor
timestamp: January 23, 2023, 12:17:55 am
content: Maybe some of the diffuser sheet has torn?

author: sdancer75
author_rank: Frequent Contributor
timestamp: January 23, 2023, 06:40:08 am
content: Quote from: AndyBeez on January 23, 2023, 12:17:55 amHow can this happen? I read it for the 1st time. Is that repairable? Can I use the diffuser from another 49 inch LCD Panel but from another brand ie Samsung?

author: Gyro
author_rank: Super Contributor
timestamp: January 23, 2023, 10:30:19 am
content: You haven't given the history of the TV, but it's the type of damage that can occur if somebody has tried to improve the generally uneven backlight illumination.

author: sdancer75
author_rank: Frequent Contributor
timestamp: January 23, 2023, 11:33:50 am
content: Quote from: Gyro on January 23, 2023, 10:30:19 amHi,There is no history at all. The TV was never opened for any type of service. The only thing I can think of is that the backlight warmed enough to tear off the diffuser. So the questions are a) Can this be fixed with clear glue? b) Can any other diffuser (ie another brand of the same size with an edge-lit feature) work if it is replaced?

author: Kleinstein
author_rank: Super Contributor
timestamp: January 23, 2023, 11:38:51 am
content: Depending on the construction the diffuser could be relatively easy accessible. One could try patching it with glue, clear tape. Spots with reduced light are usually less obvious and disturbing.

author: timenutgoblin
author_rank: Regular Contributor
timestamp: January 23, 2023, 12:49:51 pm
content: Quote from: sdancer75 on January 22, 2023, 11:03:01 pmHave you tried posting this question on the AVS Forum? Maybe they can help.https://www.avsforum.com/threads/official-lg-55-60-65-75-uh8500-thread.2326849/page-188The discussion thread is dated February, 2022. Also, there is an identical looking photo on the AVS Forum.Image URL:https://www.avsforum.com/attachments/20220213_022718-jpg.3239533/

author: sdancer75
author_rank: Frequent Contributor
timestamp: January 23, 2023, 01:25:07 pm
content: Quote from: timenutgoblin on January 23, 2023, 12:49:51 pmYes, I tried. The original photo is not mine but I have the same symptoms.I believe that now I have the basic direction of what is going wrong in this case.

author: sdancer75
author_rank: Frequent Contributor
timestamp: February 13, 2023, 07:48:29 am
content: Hi,I returned to my previous post since I found the time to open my tv. Indeed the diffused was cracked as you can see in the attached photo.I bought a cracked panel display of the same size, just to take the diffuser. Unfortunately, the diffuser was a half millimeter bigger than mine. So, can I cut the replacement diffuser to make it fit?My TV has a 3d ability. Does this new diffuser have something to do with the 3d ability of my TV set?Thanks,