To provide a luminous system using sunlight which supplies light energy with electric energy as small as possible.

The luminous system transmits the sunlight to a target place with flexible light transmitting fibers using glass fiber technology to a room which is dark even during the daytime or the like where the sunlight does not reach, or to a place where the sunlight is required. The luminous system can be used for boiling water in a newly-built house, a rebuilt house or outdoors. Also the luminous system can be used as a heat generator or a sunlight battery in the room which is dark even during the daytime. In this way, the sunlight can be utilized freely using the luminous system.