Katsuo Sakai

1942: I was born in Matsumoto city in Japan

1967: I was graduated from Waseda university the department of science and engineering. (applied physics course).1967: I entered Ricoh Co. Ltd..

1967-2005: I had been a researcher of electrophotographic copy method. I invented the one-shot two color copy method and many others. As a result, I became a patent master. I presented many papers and wrote a few books.

2005: I was retired from Ricoh Co. Ltd..2005-today: I am amateur researcher of electrostatics.