Exploration of the dark age by measuring the cosmic infrared background

This research aims to detect the first-generation stars in the early universe one billion years after Big-Bang by measuring their lights as the cosmic infrared background radiation. For this purpose, we have carried out rocket experiments (CIBER) and analysis of the AKARI satellite data. By four times of flights of CIBER we first succeeded to measure the radiation spectrum and fluctuations of the cosmic background in the optical to near-infrared wavelength. Combining the CIBER data with the AKARI data, we obtained an important observational constraint on the early universe. We have developed flight instruments for the next rocket project CIBER-2, and proceeded future cosmic infrared background missions EXZIT/solar-power-sail and SPICA satellite.