That was the problem a screensaver was designed to prevent after a period of inactivity, they’d trigger and show ever-shifting designs, and by ensuring your screen didn’t persist in displaying the same image for hours-even just the menu bar at the top of your screen, with “ File Edit ” and so on permanently showing-you could stave off burn-in. I’ve seen some ATMs that still use CRTs even today, and which have images-often multiple, overlaid images-burned into their screens. Even, in severe cases, when the monitor was switched off.
In other words, to light up.Ī problem that plagued most CRTs, though, was the potential for “burn-in”-that if the same image stayed on screen for long enough, it would persist dimly even after the image changed. These worked by directing a stream of electrons-deflected with a system of magnets at the back of the tube-at the front of the screen when the electrons hit a special phosphor coating, it would cause it to emit photons. Before flat screens became commonplace, we all used CRTs, hulking great plastic cases enclosing a heavy glass vacuum tube. Sure, today’s computers still have screensavers, but they’re usually merely decorative (one notable exception being the screensaver I use,īOINC), and no longer required to do the job of “saving screens”. In explaining this to my young cousin, I’d probably first have to explain why screensavers were invented in the first place.
0 kommentar(er)
