hi, just a question for the forum gurus: i have a number
of hp calculators with lcd displays, some segmented as the voyagers' or the 41, others dot-matrix type, as the 71b's for instance, and they never developed any stains or defects with age
however, i recently got an old sharp (not hp) basic pocket computer which has an lcd display much like the 71b's, only with yellow background, and though the machine seems completely new, no dents or other signs of physical abuse at all, the display has large blackened areas throughout,
mostly by the upper and lower edges. they appear to cover every part of the display, save the dots themselves or the indicators (deg, rad, run, pro, ...)
despite those darkened areas, the lcd display is completely functional if hard to read. my question is: what could have caused such dark zones ? i think that any stress or condition serious enough to cause them should have also caused the display to fail completely or at least would have left physical marks.
also, can this condition be cured somehow, such that the dark zones dissappear ? i tried to let the machine on running some program continuously just in case this could do any good but to no avail. thanx.