Black spots on PC1211 display

From: GE
Email: gerard.evrard@free.fr


Recently I had an *awful* shock when I saw three black spots on the upper part of the display of my TRS80-PC1 pocket Basic calculator. These spots have developped over the last few years (haven't dug out the machine since). The display still works perfectly, it is as if the spots were on 'another' plane of the LCD. Do you know what causes this ? Can it be reversed ? The machine has been stored very carefully in an opaque box at a quite constant temperature (my home...) all this time. Do you think we'll have to trash all these LCD machines at some point in the future ? How about LEDS ? Thanks, sorry for the long message.