Patent ID: 10122452

Abstract:
A system with which any abnormality can easily be found is provided. A system includes: a first modulator that generates a control signal and modulates an input signal in accordance with the generated control signal, to control luminance of a first light source that emits light according to the modulated input signal, the first modulator outputting the control signal; and a second modulator that acquires a control signal output from the first modulator and modulates an input signal in accordance with the control signal, to control luminance of a second light source that emits light according to the modulated input signal. The first modulator generates, as an extinguishing signal, the control signal for extinguishing the first light source by an extinguishing period. After a lapse of the extinguishing period, the first modulator generates, as a light ID signal, the control signal for transmitting a visible light signal by luminance variations of the first light source.