The highest contrast ratio of the Hanns.G HL226 is 80000000:1. That's over four times the contrast ratio of a 20000000:1 PC screen, which is the most common contrast ratio. Across all similar spec PC screens that were released around the same time as the HL226 the contrast ratio ranges from Mega Contrast to 100000000:1.
We think you might also be interested in some of the other PC displays that have an 80000000:1 dynamic contrast ratio currently available including cheaper LCD screens such as the HL226HPB (£88.99), or the HS221HPB (£85.90) both from Hannspree.
If the contrast ratio of this medium monitor is too low for you then you might want to look at the V226 (£95.40) (100000000:1), or the G237HL (£101.98) (100000000:1) both from Acer which is also higher rated.