months later. Using both the leading and trailing scans, AKARI achieved almost complete sky coverage in 6 months, although some regions are affected by the South Atlantic Anomaly (an anomalously higher-density region of solar protons) and the Moon [@Doi15]. AKARI observed $97\%$ of the sky twice or more during the 16 months of its cryogenic mission lifetime, and the full data set from all 16 months was used for the construction of the publicly released AKARI maps [@Doi15]. Therefore, most sky regions in the AKARI image were processed with data from different satellite (Earth) positions and lines of sight (both in the leading and trailing directions). The IPD cloud is asymmetric with respect to the Earth, and the observed ZE brightness changes with satellite position. AKARI observed the Galactic and extragalactic components along almost the same lines of sight, whereas dust in the Solar System was observed along completely different lines of sight from opposite positions, 6 months apart along the Earth’s orbit. To investigate the ZE component, we therefore divided and reprocessed each of the released AKARI far-IR maps for all four bands into two separate maps, according to whether they were observed in the leading or trailing directions. 