What JVC say:

Introducing the world's first native 30,000:1 Contrast Ratio D-ILA Front Projector, the DLA-HD100. The DLA-HD100 brings Full HD to your home with the industry's highest native contrast ratio. The "native" means that it does not rely on an iris mechanism to maximize contrast depending on the average brightness of one scene. This technical sleight of hand employed on other projectors, effectivly changes overall luminosity, so that blacks are slightly bleached in bright scenes, while light colors appear duller in dark scenes... read more

www.jvc.co.uk