Typical cellphones often have poor user interfaces — e.g. small keypads and small display screens. Researchers at Siemens have developed an interesting solution to solve this problem.
Siemens researchers have developed a cell phone featuring a built-in projector system. A laboratory model was presented at CeBIT 2005 in Hanover. The system makes it possible to project a complete keypad or display onto a surface. With a special pen, users can write on the virtual keypad and operate the phoneï¿½s functions.