Space infrared astronomy in Japan

We briefly review the recent Japanese space infrared astronomy program. We discuss the successful Infrared Telescope In Space (IRTS) which was one of the mission instruments on the Space Flyer Unit (SFU), and was optimized for the spectroscopy of diffuse infrared sources. As a second topic we discuss a proposed mission, the Infrared Imaging Surveyor (IRIS) which will be launched into a sun synchronous orbit by a Institute of Space and Astronautical Science (ISAS) MV rocket. The IRIS is an advanced survey mission whose sensitivities and spatial resolution are much better than those of IRAS. Finally we discuss a. future mission after the IRIS. One candidate mission is a cold telescope of 3 similar to 4 m aperture at the L2 point, which will be launched by a H2 rocket.