original document

This generally refers to an original document and is defined as "documents created as a definitive document to indicate certain matters" (Yuhikaku Legal Terms Dictionary, edited by the Legal Terms Study Group of the Cabinet Legislation Bureau); however, none of the laws or regulations contain provisions specifying the original document.
At the time of scanning, it usually refers to the original paper-based document.
In a broad sense, it refers to the document itself. Also, in a narrow sense, it refers to the document that the creator first created as a definitive document in order to indicate certain contents. If this meaning in a narrow sense is difficult to understand, the original document may be said to be the document from which a certified copy, extract, or copy is prepared.
In addition, it is explained in Article 14 of the "Regulations Concerning Special Rules on Certification of Calculation in the Case of Processing Using an Electronic Data Processing System, etc." (April 1, 2003, Regulations of the Board of Audit No. 4) that "the term 'original document' shall mean 'original information' and the term 'certified copy' shall mean 'a document outputting the original information.'"