are under development. Speckle noise should be reduced significantly, and thermal issues and power consumption greatly reduced. Applications Handheld projectors can be used for different applications from small conventional projectors. Since 2008 researchers are studying applications that are specifically designed for handheld projectors often using prototypes of mobile phones with an integrated projector. Mobile 21st century mobile phones have the ability to store thousands of photos and can take photos of good quality. Projector phones allow sharing them with a larger audience than on the phone's small screen. One study found that people preferred to view and share photos with projector phones, compared to using conventional mobile phones. Gaming Handheld projectors, in particular projector phones, could offer new possibilities for mobile gaming, as demonstrated by the adaptation of the PlayStation 3 game LittleBigPlanet. Players can sketch a world on a sheet of paper or use an existing physical configuration of objects and let the physics engine simulate physical procedures in this world to achieve game goals. Hand gesture recognition Size reduction of mobile devices is often limited by the size of the used display. Apart from the display a complete phone can be, for example, integrated in a headset. It has been demonstrated that pico projectors integrated in headsets could be used as interaction devices, e.g., using additional hand and finger tracking. The MIT Media Lab proposed a wearable gestural interface device named SixthSense. Chris Harrison developed a working system called Omnitouch. Finally, the Light Blue Optics Light Touch is yet another similar device. Lisa Cowan from UCSD showed a proof of concept of gesture recognition using shadow-occluding of the projector, called ShadowPuppets. A modified laser projector has been used to perform gesture recognition and finger tracking using laser-based active tracking techniques at the University of Tokyo (Smart Laser Scanner and Laser Sensing Display). Pointer-based computer control Combining a pico projector with a webcam, a laser pointer, and image processing software enables full control of any computing system via the laser pointer. Pointer on/off actions, motion patterns (e.g., dwell, repetitive visit, circles, etc.) and more can all be mapped to events which generate standard mouse or keyboard events, or user-programmable actions. References Bibliography Brennesholtz, M (2008). "Market Segment Analysis: Pico-Projectors", Insight Media Projectors Emerging technologies