PURPOSE: To obtain a refrigerator capable of utilizing energy, emitted from a light source, not only for light energy (for illumination) but also for heat energy by which air in the refrigerator is sterilized and the cooler is defrosted.

CONSTITUTION: Light, guided from a light source 1 by a light guide 2, is separated into visible rays V, ultraviolet rays UV and infrared rays IR by a wavelength separating unit 3 and the ultraviolet rays UV are transmitted by the light guide 2 so as to be utilized for the sterilization of air in a refrigerator while the infrared rays IR are transmitted by the light guide 2 so as to be utilized for the defrosting of a cooler 6. The visible rays V are branched into a plurality of lights by a light path switching unit 7 and is transmitted by the light guide 2 so as to be utilized not only for the illumination of the inside of the refrigerator but also for preventing the plane 8 of door from being frozen and becoming unmovable but also for transmitting the light by the light guide 2 so as to be used for the illumination of an indicating panel 9.