We analyzed spectral data of the astrophysical diuse emission obtained with the low-resolution spec- troscopy mode on the AKARI InfraRed Camera (IRC) in the 1.8-5.3 μm wavelength region. Advanced reduction methods specialized for slit spectroscopy of diuse sky spectra have been developed, and a catalog of 278 spectra of the diffuse sky covering a wide range of Galactic and ecliptic latitudes was constructed. Using this catalog, two other major foreground components, the zodiacal light (ZL) and the diuse Galactic light (DGL), were separated and subtracted by taking correlations with ZL brightness es- timated by the DIRBE ZL model and with the 100 μm dust thermal emission, respectively. The isotropic emission was interpreted as the extragalactic background light (EBL), which shows significant excess over the integrated light of galaxies at <4 μm.

ASTRO-F is the first Japanese dedicated infrared astronomical satellite which will be launched in 2005FY and is now in the final stage of the development. ASTRO-F is a 70 cm aperture cryogenically cooled telescope and designed for the infrared survey with much higher sensitivity and angular resolution than IRAS. We present the current status of the mission, focal plane instruments, and the observation plan now being discussed.

SPICA (Space Infrared Telescope for Cosmology and Astrophysics) is an infrared astronomical satellite with a 3.5 m cooled telescope which is very powerful in mid- and far- infrared observations and makes complementary role to JWST and Herschel. SPICA will be launched at ambient temperature without any cryogen into the Sun-Earth L2 orbit and cooled down in space to 4.5 K with use of efficient radiative cooling and mechanical coolers. The present status of SPICA and the developments of the satellite system are reported.