Some things to note: Laser diodes (which produce the structured light used by the PS technology) need to operate at a specific temperature so they hit a specif

Some things to note: Laser diodes (which produce the structured light used by the PS technology) need to operate at a specific temperature so they hit a specific frequency of light. You do this so that you can hit a frequency window for the IR filter in front of your camera. The trade-off here is to use a wider filter, but this increases the system's susceptibility to noise and outside light (windows with sun shining through them are a big problem). There is a longish delay for the laser diode to hit that frequency (that's what Kinect is doing when it's starting up; the firmware and all is ready to go in a few hundred milliseconds, but the LD needs tens of seconds to get to operating temp). It's not an instant-on device unless you can process data that has low fidelity. In addition to dumping power into a heater, you also need a cooler (a mere heat sink won't be reactive enough). More power. I really worry about battery life in a hand-held device. (I don't remember how much power laser diodes draw, but the one in the Kinect draws over 60mw). Microsoft has a metric buttload of patents in this area, both purchased and from in-house R&D. I really wonder what Apple thinks it bought.