By Julian Prokaza on Thursday, 04 October 2007
 The screen on my IBM Thinkpad X31 has a long scratch (about
20mm) one of its bottom corners. The cause? My cat, pawing the screen to chase
the mouse pointer as I was working (okay, playing with the cat). The scratch
doesn’t appear to be too deep, but it does distort the display beneath it,
although this seems to be as a result of some kind of optical effect rather
than more serious damage to the screen itself. A friend suggested using
toothpaste to buff out the scratch, much like using T-Cut to repair car
bodywork, but I’m sceptical. Have you got any better ideas?
Wendy Baddock, Plymouth
The outermost layer of a laptop's TFT screen is made from plastic, which makes
repairing scratches tricky. In theory, your friend's suggestion of using toothpaste
is sound: toothpaste is a mild abrasive, which is why it's useful for cleaning
the surfaces of our teeth. It's far too abrasive to 'buff out' a scratched plastic
surface, though, and the large, uneven particles would turn the scratch into
a foggy mess.
 You can buy products designed to buff scratches out of plastic. Many users
rate Displex
Display Polish (£3 plus P&P) highly, but you can get the same
results with Brasso.
Just dab a lint-free cloth on the Brasso wadding (don't use the wadding itself!)
and patiently polish out the scratch. Sadly, Displex and Brasso work only on
glossy screens, whereas the Thinkpad X31 has a matte finish. Try polishing it
and you'll make it worse.
 The optical effect you've noticed is the result of a change in the screen's
optical qualities. That top layer of plastic is a polarising filter, which means
the light passing through the scratched area isn't polarised. One trick is to
carefully fill the scratch with petroleum jelly (Vaseline,
or similar). Apply it with a cocktail stick and wipe off the excess with a soft
cloth in a swift motion. Petroleum jelly is closer to the refractive index of
the screen than air is, so it often does a good job of making the scratch less
noticeable.
Laptop screen protectors are available (similar to those available for PDAs),
but we were unable to find a supplier in the UK. US supplier Nushield
will ship to the UK though. Finally, a piece of chamois leather or soft, lint-free
cloth cut to fit over the keyboard will protect the screen if the lid gets pressed
down while a laptop is in transit.
Solution 1 Polishing
Brasso is a cheap fix for a lightly scratched glossy screen. Dab a soft, lint-free
cloth on to the Brasso wadding, then use the cloth to polish the scratched part
of the screen. Brasso is abrasive and, with care and patience, will restore
the shine to glossy plastic.
Solution 2 Filling
You can't polish out a deep scratch, but you can reduce its visibility by filling
it with petroleum jelly. Clean the screen, then use a cocktail stick to fill
the scratch with jelly. Wipe off the excess with one swift motion of a lint-free
cloth - any other method may wipe jelly over the screen, or out of the scratch.
 Solution 3 Prevention
You can protect a laptop screen while the lid is closed by cutting a rectangle
of chamois leather or other soft, lint-free material to fit over the keyboard.
Leave it in position when you close the lid, and it will protect the screen
from marks and scratches from the keyboard and pointing device.
|
