The highest contrast ratio of the HP 24es is 1000000:1. That's 99% less contrast ratio than a 100000000:1 PC screen, which is the most frequently found contrast ratio. Across all latest PC screens the contrast ratio ranges from Mega Contrast (worst) to 100000000:1 (best).
Alternative LCD screens that have a 1000000:1 dynamic contrast ratio currently available which you might also want to consider include cheaper PC displays such as the HP 22es (£99.54).
If the contrast ratio of this PC screen is too low for you then you might want to consider the DELL P2314H (2000000:1 and cheaper); or the DELL U2413 (£279.00) (2000000:1 and higher rated).