Initial on-orbit modulation transfer function performance analysis for geostationary ocean color imager

Eunsong Oh, Sug Whan Kim, Seongick Cho, Joo Hyung Ryu, Yu Hwan Ahn

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3 Citations (Scopus)


The world's first geostationary ocean color imager (GOCI) is a three-mirror anastigmat optical system 140mm in diameter. Designed for 500 m ground sampling distance, this paper deals with on-orbit modulation transfer function (MTF)measurement and analysis for GOCI. First, the knife-edge and point source methods were applied to the 8th band (865 nm) image measured April 5th, 2011. The target details used are the coastlines of the Korean peninsula and of Japan, and an island 400 meters in diameter. The resulting MTFs are 0.35 and 0.34 for the Korean East Coastline and Japanese West Coastline edge targets, respectively, and 0.38 for the island target. The daily and seasonal MTF variations at the Nyquist frequency were also checked, and the result is 0.32 ± 0.04 on average. From these results, we confirm that the GOCI on-orbit MTF performance satisfies the design requirements of 0.32 for 865nm wavelength.

Original languageEnglish
Pages (from-to)199-208
Number of pages10
JournalJournal of Astronomy and Space Sciences
Issue number2
Publication statusPublished - 2012 Jun


All Science Journal Classification (ASJC) codes

  • Physics and Astronomy(all)
  • Earth and Planetary Sciences(all)

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