Redmond-based >Microsoft and New York-based multi-touch screen maker Perceptive Pixel said Monday that Microsoft has acquired Perceptive Pixel. Financial terms of the deal were not disclosed. Perceptive Pixel develops multi-touch, video walls and screens. Microsoft said it will acquire PPI to help power Windows 8 based PCs. Perceptive Pixel's touch screens have been used by CNN and others, to present very large screen, touch sensitive displays.