Born: 12 May 1924, Stettin
Died: 31 December 2002, Hamburg
"A successful inventor actually is an entrepreneur, who must consider what tomorrow's market will need."
Dethloff is the co-developer of the chip card and the inventor of the microprocessor card.
Since 1981, the chip card has been used in more and more areas of life and meanwhile has changed daily routines.
In 1949, Dethloff passed the examination for radio technicians (master of radio engineering). One year later only, he founded the "Dethloff Elektronik" company and produced intercommunication systems for ships. After selling the company, he started to build up the "Jürgen Dethloff Hamburg" enterprise, in 1965.
Jürgen Dethloff and Helmut Göttrup jointly filed a patent application for a plastic card with integrated circuit with the German Patent Office in 1969. The title of the patent application was "identification switch" which later became known as the chip card.
In 1977, Dethloff applied for a patent for the microprocessor card, which today can be found in every wallet as phone card, credit card, eurocheque card or patient's data card.
Plastic chip cards contain one or more semiconductor chips. We distinguish memory cards and microprocessor cards.
Memory cards have simple logical circuits with an additional readable and writable memory. They are used for example for pre-paid phone cards and health insurance cards.
Microprocessor cards, so-called smart cards, can be freely programmed which provides high functionality. An identifier allows to read or write data.
In 1984, the phone card of France Telecom was the first large-scale application of the chip card. Since then, it has been used as EC/credit card for cashless payment and in the telecommunications industry as phone card or calling card for mobile phones.
Dethloff did not only achieve great success as inventor but also as an advisor for innovative applications of the microprocessor card in the communications industry.
The chip card will be covering a wide variety of potential applications in many other areas in the future. Dethloff always advocated the view that the chip card should not become an "instrument of the ruling class".
To find out more about Jürgen Dethloff's patents, go to DEPATISnet
© B. Struif
Patent document DE-2760486C2
(PDF - 400 KB)
Dipl.-Ing. Horst Weißenberger