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Digitization of library materials

The National Diet Library (NDL) has been converting the content of materials into other media to achieve compatibility of use and preservation. A microfilming program was originally used as a method for preserving valuable materials, but since 2009, the NDL has been in general digitizing them for the following purposes.

  1. Preservation of materials
    The NDL has been digitizing materials and providing digitized contents as an alternative for use to prevent original materials from deterioration and damage by frequent use
  2. Digital library service
    Digitization improves convenience in reading materials. The NDL has been providing on the Internet digitized contents which cleared copyright so that people can access them anytime and anywhere on the web without visiting the NDL in person.

Overview of the digitized contents

Material type Explanation
Books Books acquired by the NDL up to 1968
Parts of books related to earthquakes and natural disasters (including books acquired after 1968)
Periodicals Periodicals published more than five years ago
Rare Books and Old Materials Rare books, Semi-rare books, Japanese old books up to the Edo Period and Chinese old books up to the Qing Dynasty
Doctoral Dissertations Japanese doctoral dissertations received by the NDL between FY1991 and FY2000
Official Gazettes Japanese official gazettes from the first issue published on July 2, 1883 to the issue of April 30, 1952
Modern Japanese Political History Materials Parts of the collection digitized for the Online Gallery; includes correspondences, manuscripts, diaries, and photographs, which originally belonged to eminent figures of Japanese modern political history
Materials on the Allied Occupation of Japan From the documents on the Allied Occupation of Japan held by the National Archives and Records Administration of the United States, parts of the Records of U.S. Strategic Bombing Survey, the Records of General Headquarters, Far East Command, etc.
The Gordon W. Prange Collection Parts of the books in the Gordon W. Prange Collection (Japanese publications submitted to the Allied Forces for censorship)
Historical Recordings Collection Sound recordings of music, speeches, etc. on 78rpm records and metal discs used to press commercial releases from around 1900 to 1950
Science Film Science films collected and digitized by the Incorporated Nonprofit Organization Society for the Support of the Science Film Museum
Scripts Parts of TV and radio scripts up to 1980 which were donated to the NDL by the Consortium for the Promotion of Broadcast Script Archives in Japan.
Music manuscripts Parts of music manuscripts and documents related to modern Japanese composers.
Newspapers The wall newspaper which was published six days after the Great East Japan Earthquake by the Ishinomaki Hibi Shinbun Newspaper Co.

There are some materials not digitized even if included in the above explanation. For more information please see the National Diet Library Digital Collections.

Current situation of digitized contents (as of January 2017)

Material type Number of contents 1
Available Online Available only at the NDL 2 Total
Total 500,000 2,110,000 2,620,000
Books 350,000 610,000 970,000
Periodicals 10,000 1,260,000 1,270,000
Rare Books and Old Materials 70,000 20,000 90,000
Doctoral Dissertations 15,000 125,000 140,000
Official Gazettes 20,000 20,000
Modern Japanese Political History Materials 300 300
Materials on the Allied Occupation of Japan 40,000 1,000 40,000
The Gordon W. Prange Collection 40,000 40,000
Historical Recordings Collection 2,000 47,000 50,000
Science Film 300 300
Scripts 2 33 35
Music manuscripts 21 21
Collections from Other Institutions 6 11 17


  1. This figure is the round number of items the NDL has been providing.
  2. The number includes items which are also accessible in the partner libraries.

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