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Historical sequence of laboratories


The Physics Laboratory

In 1947 the Physics Laboratory PTT returned to the "Vlakte van Waalsdorp" and joined the TNO-organization in 1948 under the name Physics Laboratory TNO. TNO stands for the Netherlands Organization for Applied Scientific Research. In Waalsdorp the laboratory continued the pre-war activities in the domain of radio, radar and infrared technology. Visits to allied countries showed the extensive growth of defense research resulting in technical achievements in military equipment during the war. To make up for the lost years and to establish a international position in this respect new areas of investigation had to be started such as passive and active sea going sonar, special radar subjects, electronic computing and operation research. In the domain of digital fire control the laboratory became worldwide a leading role in 1960 and introduced the USA in this technology.

The accommodations had been enlarged with a stone two storey building with annexes and outside wooden sheds and temporary provisions. So a new three storey building, the main part of the present present TNO location The Hague Waalsdorp building, was taken into use in 1967 containing many in house laboratory facilities. Here research for the support of the Armed Forces increased again in both intensity and scope whereas staff number increased to more than 300 in 1984.

The Physics Laboratory in 1965 - painting by G.Mooij (click to view the details)

Laboratory for Electronic Developments (LEO(K))

Von Weiler returned in 1946 from England continuing his radar development and advisory work in service of the Royal Netherlands Navy, which he joined in England in 1940. He was appointed head of the Development and Testing Department of the Royal Netherlands Navy Radio Service in Oegstgeest. This department with a staff of 25 was renamed LEO (Laboratory for Electronic Developments for the Royal Navy) in 1950, focussing on the immediate needs in operational equipment for radio communication and radar. Five years later the scope of work was extended to include Army and Airforce, changing the name accordingly to LEOK (K for "Armed Forces"). The transition to a new two storey building in 1958 met the need for more space to handle artillery- and warning radar systems as well as procedure training- and simulation equipment for various purposes. Other activities concerned special servo transmissions and equipment for underwater noise registration and analysis. By 1977 the number of people employed had risen to about 150 with ir F. van Hutten as director. In that year the Netherlands Armed Forces decided to drop the military status of LEOK by transferring the laboratory to the TNO-organization.

TNO Physics and Electronics Laboratory (TNO-FEL)

The continued discussion about the organization of the future tasks of the both laboratories resulted in the decision to integrate both at one locality. The capacity of the Waalsdorp laboratory was enlarged and the new TNO Physics and Electronics Laboratory (TNO-FEL) started December 1st 1984, exactly 57 years after defense research at Waalsdorp had begun.

TNO-FEL has since continued its traditional role as one of the three institutes of the TNO Defense Organisation. The laboratory conducts research and development sponsored or contracted by the Ministry of Defense, taking into account the changing role and definition of defense. At the same time a market-oriented approach is practiced related to domestic and foreign civil demands. To meet the requirements a staff of nearly 500 people is employed divided into five groups of activities:

  • Operations Research and Business Management
  • Command & Control and Simulation
  • Smart Sensor Solutions
  • Observation Systems
  • Telecommunication and Security (moved mid 2003 to TNO Telecom).


On December 31, 2005, TNO's organisational structure with 14 institutes was replaced by a structure which clustered the institutes, The three Defence laboratories together were named TNO Defence, Security and Safety. On December 31, 2010 TNO replaced this group structure by the 'one' TNO matrix organisational structure. To a large extend, the expertise areas at location The Hague Waalsdorp work for the theme Defence, Safety and Security.


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