The V225HQL has a maximum contrast ratio of 100000000:1. That's over five times the contrast ratio of a 20000000:1 PC display, which is the most common contrast ratio.
A 100000000:1 dynamic contrast ratio is actually the best contrast ratio across all medium monitors that are a similar age to the V225HQL.
The worst contrast ratio amongst similar types of PC display is Mega Contrast.
There are a number of alternative flatpanel monitors that have a 100000000:1 dynamic contrast ratio currently available that you might want to consider including the Acer V236HL (£124.74) which has a better Rating; or the Acer S240HL (£66.97) which is cheaper.