This is the Joyo Kanji. This is a Tablet rather, or a poster of the 1,945 common-use characters as determined by the Ministry of Education in 1981.
See on Joyo Kanji. Kanji tähestiku juhend ehk plakat  1945 enimkasutatava märgiga, mille koostas Jaapani  Haridusministeerium 1981. aastal.