The former president and chairman of Sony, Norio Ohga, who was credited with developing the compact disc, has died aged 81, the company has said. Ohga was still a senior adviser to the company at the time of his death.
In 1953, Sony's co-founders recruited Ohga while he was still studying at the Tokyo National University of Fine Arts and Music and hoping to pursue a career as an opera singer. They sensed his knowledge of sound and electrical engineering would benefit the firm.
During the development of the CD, it was Ohga who pushed for a disc that was 12cm (4.8in) in diameter, because it provided sufficient capacity at 75 minutes to store all of Beethoven's Ninth Symphony.
Sony sold the world's first CD in 1982 and CDs overtook LP record sales in Japan five years later. Ohga's specifications are still used today, and have shaped formats developed since, including MiniDisc and DVD.
Ohga also presided over the launch of Sony's game business, which went on to develop the successful "PlayStation" console.
Ohga stepped down as Sony's president in 1995 and continued to serve as chairman and representative director until 2000. He was also the chairman of the Tokyo Philharmonic Orchestra.
Source : BBC