NPL research has contributed to
physical science,
materials science,
computing, and
bioscience. Applications have been found in
ship design,
aircraft development,
radar,
computer networking, and
global positioning.
Atomic clocks at right, with Jack Perry The first accurate atomic clock, a
caesium standard based on a certain transition of the
caesium-133 atom, was built by
Louis Essen and Jack Parry in 1955 at NPL. Calibration of the caesium standard atomic clock was carried out by the use of the astronomical time scale
ephemeris time (ET). This led to the internationally agreed definition of the latest
SI second being based on atomic time.
Computing Early computers NPL has undertaken pioneering computer research since the mid-1940s. From 1945,
Alan Turing led the design of the
Automatic Computing Engine (ACE) computer. The ACE project was overambitious and floundered, leading to Turing's departure.
Donald Davies took the project over and concentrated on delivering the less ambitious
Pilot ACE computer, which first worked in May 1950. Among those who worked on the project was American computer pioneer
Harry Huskey. A commercial spin-off,
DEUCE was manufactured by
English Electric Computers and became one of the best-selling machines of the 1950s. Davies designed and proposed a national commercial data network in his 1965
Proposal for the Development of a National Communications Service for On-line Data Processing. Subsequently, the NPL team, led by
Roger Scantlebury, were the first to implement packet switching in the local-area
NPL network in early 1969, which operated until 1986. They carried out work to simulate the performance of a wide-area packet-switched network capable of providing data communications to most of the U.K. Their research and practice influenced the
ARPANET in the United States, the forerunner of the
Internet, and other researchers in the UK and Europe, including
Louis Pouzin, as well as in Japan. NPL sponsors a gallery, opened in 2009, about the development of packet switching and "Technology of the Internet" at
The National Museum of Computing.
Internetworking NPL
internetworking research was led by Davies, Derek Barber and Scantlebury, who were members of the
International Network Working Group (INWG). They observed that connecting heterogeneous computer networks creates a "basic dilemma" since a common host protocol would require restructuring the existing networks. To study this, NPL connected with the
European Informatics Network (Barber directed the project and Scantlebury led the UK technical contribution) by translating between two different host protocols; that is, using a
gateway. Concurrently, the NPL connection to the Post Office
Experimental Packet Switched Service used a common host protocol in both networks. NPL research confirmed establishing a common host protocol would be more reliable and efficient. The EIN protocol helped to launch the proposed INWG standard.
Bob Kahn and
Vint Cerf acknowledged Davies and Scantlebury in their 1974 paper "
A Protocol for Packet Network Intercommunication". Barber was involved in Internet design discussions in 1980.
Scrapbook Scrapbook was an information storage and retrieval system that went live in mid-1971. It included what would now be called
word processing,
e-mail and
hypertext, anticipating many elements of the
World Wide Web. The project was managed by David Yates who said of it "We had a community of bright people that were interested in new things, they were good fodder for a system like Scrapbook" and "When we had more than one Scrapbook system, hyperlinks could go across the network without the user knowing what was happening". It was decided that any commercial development of Scrapbook should be left to industry and it was licensed to Triad and then to BT who marketed it as Milepost and developed a transaction processor as an additional feature. Various implementations were marketed on
DEC,
IBM and
ITL machines. All NPL implementations of Scrapbook were closed down in 1984.
Email Derek Barber proposed a network mail protocol and implemented it on the
EIN in 1979, the first European implementation of
electronic mail.
Jon Postel referenced Barber's work in his first paper on Internet email, published in the
Internet Experiment Note series.
Secure communication In the early 1990s, the NPL developed three formal specifications of the
MAA: one in
Z, one in
LOTOS, and one in
VDM. The VDM specification became part of the 1992 revision of the International Standard 8731–2, and three implementations in
C,
Miranda, and
Modula-2.
Electromagnetics A 2020 study by researchers from
Queen Mary University of London and NPL successfully used microwaves to measure blood-based molecules known to be influenced by dehydration.
Metrology The National Physical Laboratory is involved with new developments in
metrology, such as researching metrology for, and standardising,
nanotechnology. It is mainly based at the Teddington site, but also has a site in
Huddersfield for
dimensional metrology and an
underwater acoustics facility at
Wraysbury Reservoir near
Heathrow Airport.
Timing The National Timing Centre (NTC) Programme has been developed to provide a time infrastructure system for research and technology. In 2025, £68 million was awarded to the National Physical Laboratory to further develop the NTC. ==Directors of NPL==