Recently I have had many cases of users with the ThinkVision 14" LT1421 portable lenovo display complain of display issues with either fuzzy or blurry images
The Fix
The first two steps will be to download the latest drivers for the portable screen and display link drivers
1. Portable Screen -> http://support.lenovo.com/au/en/downloads/ds020544
2. Display Link -> http://www.displaylink.com/downloads/windows
If the screen is still blurry you can try using cleartype
Full HD Laptops
For those with full HD laptops using the portable screen in extended displays mode
Right click the desktop and select Personalize
Click on Display (bottom left)
Select Apply to all Monitors
select Medium,Small or Large. (Medium is a good test)
apply and sign out and back in
Lenovo Scaling
I have also seen lenovo scaling mess with resolutions and cause blurry images, install and uninstall and see if this changes your monitor display quality.
that is all hope it helps
