| 主权项 |
1. An unauthorized use preventing system of a projection-type projector, the system comprising:
an unauthorized use preventing device arranged separately from said projection-type projector; and a security section provided in said projection-type projector, wherein said unauthorized use preventing device includes:
a first measuring unit that measures a global position thereof and outputs the global position as first position information; anda first transmission unit that wirelessly transmits said first position information to an outside, said security section includes:
a second measuring unit that measures a global position thereof and outputs the global position as second position information;a first receiving unit that receives said first position information;a position comparison unit that receives said first position information and said second position information, determines whether an inter-instrument distance calculated based on both pieces of said information is less than a threshold distance or equal to or more than said threshold distance, and outputs a result of the determination as a position comparison result signal; anda logical product calculation unit that receives said position comparison result signal and a power supply turning-on signal indicating whether or not a power supply of said projection-type projector is turned on, and calculates and outputs a logical product of both of said signals, and it is decided whether or not to light a light source of said projection-type projector based on an output signal of said logical product calculation unit, so that unauthorized use of said projection-type projector is prevented. |
