Image output device, image output system, image output method, and mobile information processing device

The invention relates to an image otuput device, an image output system, an image output method, and a mobile information processing device. The image output device includes a transmitting unit and a receiving unit. The transmitting unit transmits, via visible-light communication, information for identifying the image output device as a destination of second communication different from the visible-light communication. The receiving unit receives a print instruction from a mobile information processing device via the second communication in accordance with the information. The transmitting unit stops emission of light for the visible-light communication in response to receipt of the print instruction by the receiving unit.