Projector, electronic whiteboard system using projector and method of acquiring indicated point

摘要

An electronic whiteboard system has light emitting elements mounted on ultrasonic wave receivers of a signal processor, and an imager device for imaging the light emitting elements and a projection test pattern of a projector to acquire a positional relationship between the light emitting elements and an image projected from the projector. The electronic whiteboard system can facilitate initialization of the coordinates with the acquired positional relationship.