I have a 17" digimate tft that was fine until i started using it with
my laptop as an extended monitor.
Now the backlight comes on whenever a change is made to the display
properties or if the monitor is switched on, but then after a couple of
seconds it switches off. Previously I found that eventually it would
stay on but could not figure out what was causing the problem. Now it
swtiches off every time even when connected to a pc as the primary
monitor. I have checked the laptop and other monitors work fine with
it.
The monitors is only about 2 months old.
Any Ideas???
Monitors use cold cathode fluorescent lamps (CCFL) and a high
voltage inverter. The high voltage inverter is able to supply
only a couple of milliamps to the lamp. If the inverter is overloaded
for any reason, that can cause the inverter to switch off.
(Inverter and CCFL lamp, for an LCD monitor)
http://www.anok.ceti.pl/inverter/inverter1.jpg
The only user control you can experiment with, is change the
intensity setting of the screen. That may be accessible via
the OSD (on screen display) interface on the monitor. You may
not be able to see what you are doing, which will be the hard
part. Sometimes, if you drop the screen intensity, that changes
the output setting for the inverter. The inverter is asked
to produce less current, and the inverter will stay on for
longer. (The OSD display setting, drives a signal to the inverter,
and that signal is what tells the inverter how much voltage to
produce. Turning down the screen intensity, means the inverter
doesn't have to work as hard.)
If reducing the screen intensity makes the screen stay on, then
you know that eventually the inverter will stop entirely. This
workaround tells you the problem is with the inverter, and
whatever problem the inverter has, will only get worse with time.
Sometimes, it is a bad connection between the inverter and the
lamp. There is a cable and connector of some sort. Some people
find that replugging the cable inside the monitor will make
it work for a while.
Exact replacement parts for the monitor, would be the best
way to repair it. If the monitor is 2 months old, and the
monitor had a one year warranty, you should use the warranty
to get it fixed. It will be a lot harder to find a good
replacement lamp or inverter, by shopping for it on the
Internet. Whoever manufactured the display, will have a
supply of proper replacement parts.
Paul