The behind-the-scenes tales of hit products and creations from Japan: this is Japan's Top Inventions. This time, an invention with which you confirm your identity just by holding out your palm: palm vein authentication. This world's first biometric technology, developed by a large Japanese manufacturer in 2003, reads the unique vein patterns in the palm to verify users' identities. It's now used in over 60 countries and regions. Discover the little-known origin story behind this top invention.