Japan has taken measures concerning the waiver of visa requirements for 69 countries and regions. See the following web site for details:
http://www.mofa.go.jp/j_info/visit/visa/short/novisa.html
Citizens from other countries should have a valid visa before departure. Several documents provided by the Japanese side are necessary before you submit a visa application to your nearest Japanese embassy. Please contact the Secretariat [14th_apctp(at)crystal.k.u-tokyo.ac.jp] about obtaining the documents. Details about visa applications can be found on the following web page: http://www.mofa.go.jp/j_info/visit/visa/index.html