The 1000 yen note (¥1000) is currently the lowest value yen banknote and has been used since 1945, excluding a brief period between 1946 and 1950 during the American occupation of Japan. The fifth series (series E) notes are currently in circulation, and are the smallest of the three common bank notes, measuring 150 x 76 mm. The front side shows a portrait of Hideyo Noguchi, who in 1911 discovered the agent of syphilis as the cause of progressive paralytic disease. The reverse depicts Mount Fuji and cherry blossoms, adapted from a photograph by Koyo Okada. It was first issued on 1 November 2004. Extensive anti-counterfeiting measures are present in the newest banknotes. They include intaglio printing, holograms, microprinting, fluorescent ink, latent images, watermarks, and angle-sensitive