Anyone else ever seen this effect on an LCD display, or have any thoughts on
how it could occur ?

Might the screen have been an LCD, or a CRT, which "bounces" the image
onto a translucent display screen via a mirror or lens arrangement of
some sort? All sort of opportunity for linearity and misalignment
issues with that sort of arrangement.

--
Dave Platt AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!