Japan Visa Information:

Visa On the basis of the Law for the Establishment of the Ministry of Foreign Affairs, visas granted by the Japanese Government are issued only by embassies or consulates under the Ministry of Foreign Affairs.

 A visa cannot be acquired after arriving in Japan.
A visa is an indication of the judgement that a foreigner wishing to enter Japan should be appropriate to enter and stay in Japan.
A visa itself does not guarantee landing (status of residence) permission. Please note that possession of a visa is just one condition for application for landing at an airport or seaport.
Although there are some countries that do give visas the function of a guarantee of landing permission, most countries, like Japan, have a system which requires permission from immigration authorities as well as a visa.

Landing permission

Landing permission is stamped in a foreigner's passport by immigration officers at the airport or seaport where he or she goes through immigration procedures. It is this landing permission, not a visa, that serves as the legal basis for the foreigner's stay in Japan. A visa is only a recommendation and does not automatically guarantee landing permission.
When a foreigner wishing to enter Japan arrives at an airport or seaport in Japan, he or she first of all has to apply to an immigration officer for landing permission. The immigration officer will check the validity of the foreigner's passport, the existence of a visa when necessary, the validity of the visa, the purpose of entering Japan, the scheduled period of stay, and so on. Landing permission will be granted only if all the conditions stipulated in the Immigration Control Act, including those being checked by the immigration officer, are met.
The stamp of landing permission states not only the date and port of entry but also the status of residence (often referred to as immigration status) of the foreigner, which determines the activities in which that foreigner is permitted to engage in Japan and the term of residence of his or her immigration status.
The receipt and validity of landing permission are prerequisites for any future applications at a regional immigration authority in Japan for a specific purpose, such as extension of term of residence or change of status of residence. Any such applications must be made at the nearest regional immigration authority to the applicant's place of residence in Japan.
When an immigration officer at the port of entry completes an examination for landing and grants landing permission, the visa immediately becomes invalid (although multiple visas remain valid until the date of their expiration). After that, as explained above, it is the stamp of landing permission that serves as the legal basis for the foreigner's stay in Japan.

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