LCD Screen Cracked Appearance

I think it looks like stress fractures. Probably induced by changes in temperature.

You find this exchange interesting. In this particular case, it looks like there's no terminology, because the manufacturer won't admit there's a problem.

Not repairable. Replace it.

Was this LCD exposed to sunlight, UV or extreme temperature fluctuations? To me it looks like it took too much UV. Was it, perhaps, a fish finder or GPS screen left on a dash board or in a boat?

There are quite a few plastics that can't handle the exposure.

It was fitted to the control center for chiller system. Basically it was not exposed to the outdoor environment.

There was a situation where aircraft displays were failing rather like that. The boundary 'brown out' is also very reminiscent. I think it was discussed on CR4

It turned out that the frames were too tightly fitted and lacked allowance for thermal expansion rates and flexing.

So far as search terms go, "LCD cracks" or cracking and "LCD failure" seem to bring up numerous examples.

"There was a situation where aircraft displays were failing rather like that. The boundary 'brown out' is also very reminiscent. I think it was discussed on CR4"

If you can find the link of the discussion in CR4, please let me know.

They do that sometimes.

You say cracked appearance, rather than cracked. Does that mean the display still works? If so it may just be that only the polarizer is cracked due to thermal stress. Some industrial grade LCDs include a heater layer to allow the display to operate at temperatures near or below freezing. If the heater goes out of control the LCD overheats and the polarizer gets cooked. If the glass itself is not cracked the cell may still be functional and the display could be fixed. If the display is still under warranty, the manufacturer could repair the heater circuit and replace the polarizers. Otherwise, just buy a new LCD.

'Browning' of an LCD is due to sunlight (UV) baking the front polarizer. In that case the polarizer exhibits stress lines and cracks along the polarization axis, which runs at a 45 degree angle to the face of the display. This is not a case of browning.

I'm not sure if it really cracked, the surface is smooth on the outside so if it was indeed cracked, it would be on the inside.

If there is a layer of glass laminated to the front of the LCD, this cover galss may still be intact while the polarizer directly behind it got cracked.

A second possibility is that the rear polarizer is the one that got cracked.

If you examine the display with a microscope or strong jeweler's loupe you should be able to determine where the cracking occurred. If the LCD cell itself had cracked, the LC fluid would have moved away from the cracks, leaving white zones or rainbow colored zones around the LCD. I'm fairly certian that you have a cracked polarizer.

Ref:

#2 A good link for study.

In that discussion though the picture is not anywhere but all posters complain the condition visible when powered. But the picture in this discussion is taken without power which clearly an indication of physical damage which can only be due to pressure on the sceen.

It was said that prior to dismantling the device, the display on the screen was 'scrambled' (illegible) and the backlight was on. During a re-examination, one of the circuit breakers in the control center tripped as soon as power is supplied to the LCD device.

Typical terminology we use is mud crack.

'Mud crack' is a very descriptive term to use - I like it!

Another term that has been used to describe plastics cracked like that is 'crazed'. I do agree with others that the cracking appears to be in one of the polarizing layers, specifically the front one, which is of course plastic.