A collage showing Bank of Japan Governor Haruhiko Kuroda, various cashless payment options available at a convenience store in Tokyo and a smartphone showing an application for Cambodia's central bank digital currency "Bakong." (Photo courtesy of Soramitsu Co.) (Kyodo)

TOKYO - The Bank of Japan on Monday began a year-long experiment to check the basic functions of a central bank digital currency as its Chinese, European and U.S. peers are ramping up their own efforts toward introducing the new payment form.