I don't know how Mitsubishi apply the lasers to the DLP transducer, but if I were doing it, I'd put the lasers through a diffractor, to get a line, then use a rotating reflector - maybe octagonal - to scan the coloured lines across the DLP array. I reckon that would work better than trying to illuminate the whole chip on one go. I think supermarket barcode readers use a similar trick.
However, I think they may have left this technology too late for it to have any commercial success as it looks like OLED will be the next big thing for large displays.