Tektronix LCD screen Bad


2009-09-15 9:13 am
I have a TDS220 scope which has bad LCD screen, any idea how the bad LCD screen happen ? Is LCD screen will turn bad after some years ?

That looks to me like one of two things.
1) The layers within the LCD have become delaminated which results in the liquid crystal leaking everywhere. This is commonly called the black dot or more often black hole (or sometimes black hole of death because it is signs of an impending irreversible failure of the panel). It often starts as a black dot (or more than one) which grows and grows. It's not common but not unheard of, especially in older LCD panels.
2)The screen was cracked. Whether its due to aging (if they used plastics) or mechanical stress (impact, torsion, etc) I can't say. I can say in the second image it looks cracked.