Koichirou Aiba is one of Japan's most popular potters. He was born in 1944, and is currently retired. He is husband to 'Kouso', and father to 'Juko' (Kuniaki Aiba), who now runs the Koyo kiln, which he built in 1970. 
He was from a family of potters, albeit not of bonsai containers. 
He is most famous for his superb oribe yu glazes, which can arguably rival those of Ino Shukuho, and Heian Tofukuji. However he does also produces superb unglazed pots, as well as suiban, and some beautiful pots with carved motifs. 
The Japanese fan stamp (or ginko leaf?!) are his premiere line of pots, and are often carved from a single block of clay, unique glazes, and more detailed designs. 

Texts courtesy of topshelfbonsaipots.co.uk for which Alex has kindly given us permission to use.