Mr Ottens died on Saturday at age 94, Philips confirmed.
A structural engineer who trained at the prestigious Technical University in Delft, he joined Philips in 1952 and was head of the Dutch company’s product development department when he began work on an alternative for existing tape recorders with their cumbersome large spools of tape.
His goal was simple.
Make tapes and their players far more portable and easier to use.
“During the development of the cassette tape, in the early 1960s, he had a wooden block made that fit exactly in his coat pocket,” said Olga Coolen, director of the Philips Museum in the southern city of Eindhoven.
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