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The PTB's 1995 Annual Report Published


Die Physikalisch-Technische Bundesanstalt (PTB) Braunschweig und Berlin hat ihren 327 Seiten umfassenden Jahresbericht für das Jahr 1995 vorgelegt.

The Physikalisch-Technische Bundesanstalt (PTB), Braunschweig and Berlin, has published its 327-page Annual Report (in German language) about the year 1995.

In this Report, the PTB gives a survey of its extensive activities and of the results achieved in the year under review.

The PTB will be pleased to explain details of its work. Please address your inquiries to

Pressestelle der PTB
Telephone: +49 531/592 3005 to 3007
Fax: +49 531/592-3008
e-mail: presse(at)ptb.de

If desired, arrangements will be made for those interested to meet scientists for discussions.

The Annual Report can be obtained from:
Physikalisch-Technische Bundesanstalt
Referat Schrifttum
Postfach 3345
D-38023 Braunschweig
e-mail: Hans-Guenter.Gillar(at)ptb.de

Some interesting dates and information from the PTB's 1995 Annual Report:

Highlights of the year:

Within the framework of an official ceremony held at the PTB on March 27, the Federal Minister of Economics, Dr. Günter Rexrodt, appointed Professor Dr. Ernst Otto Göbel to be the new President of the Physikalisch-Technische Bundesanstalt Braunschweig and Berlin.
Before, Prof. Dr.-Ing. Dr.-Ing. E.h. Dieter Kind had been discharged after a period of office of almost twenty years as President of the PTB.

The increasing demands of the public in general and of political circles for the "lean" state and for a more efficient public administration are a challenge also for the PTB. As a result of discussions of the PTB executive about the strategy to be adopted, a concept has been formulated which will make it possible to meet the changed demands. In addition, criteria have been established according to which the priorities will be set for future work. It is planned to create greater and thus more flexible structures by reducing the number of organizational units, and to have work carried out to an ever increasing extent within the scope of projects.

These general topics were also in the center of discussions held with two undersecretaries from the Federal Ministry of Economics on the occasion of their visits to the PTB. On March 23, Dr. Norbert Lammert, parliamentary undersecretary, informed himself about the PTB's standard of performance, and on October 5, Dr. Johannes Ludewig, undersecretary and at the same time the Federal Government's authorized agent for the new federal states, informed himself about the PTB's contribution to the establishment of an all-German metrological infrastructure.

Within the framework of intensified public relations work, the PTB has been presenting itself since the middle of the year in the Internet under www.ptb.de.

On October 4 and 5, the 125th International Seminar on "Quantitative Microscopy" was held. About 100 experts from research and industry discussed a large variety of topics concerning the development of miscroscopic methods and their application to the measurement of geometric quantities. In addition to light-optical and electron-optical microscopy, the latest scanning probe methods were dealt with.

From the area of international cooperation:

  • The PTB will be able to meet the challenges of further "Europeanization" in the field of legal metrology. Considerable funds were spent in almost all laboratories concerned with tasks from the area regulated by law or with DKD tasks, to implement rationalization measures aimed at reducing the periods required for executing an order and lowering the costs involved. There are also increasing endeavours throughout the world to further harmonize metrology on both the international and the supra-regional level.
  • From October 9 to 13, the 20th General Conference on Weights and Measures (CGPM, Conférence Générale des Poids et Mesures) was held in Paris; Prof. Göbel, Prof. Kose and Prof. Kind in his capacity as the President of CIPM (Comité International des Poids et Mesures) participated. One of the central topics discussed was a model for ensuring international comparability and traceability.
  • The DKD's intensive cooperation in the bodies of the EAL (European Organisation for Accreditation of Laboratories), of the committee "Calibration and Testing Activities" in particular which is headed by the DKD, was successfully continued in the year under review. The aim is to create the basis for the mutual recognition of the calibration and test certificates within the framework of a multilateral agreement to which 12 European countries have so far acceded.
  • The main topics of the annual meeting of the EUROMET Committee (European Collaboration on Metrology) held on May 18 and 19 were the drawing-up of a guideline for quality management in the national institutes of metrology, the associated membership of national institutes from East Europe and the establishment of a network for the reliable and consistent tracing-back of measurement results in Europe.

From the field of research:

  • Owing to the considerably improved production facilities in its new clean room center, the PTB has succeeded in optimizing the circuits for Josephson voltage standards to such a degree that stable d.c. voltages of more than 10 V are generated. One of the new 10 V circuits from PTB production was presented to the BIPM (Bureau International des Poids et Mesures) on the occasion of the meeting of the Advisory Committee of Weights and Measures.
  • A similar success has been achieved in the production of samples for the realization of the quantum Hall effect. The MBE (Molecular Beam Epitaxy) facility put into operation at the end of the year allowed samples to be produced shortly afterwards which satisfy highest requirements. Samples submitted to the BIPM in Paris and to the National Institute of Metrology in Beijing were successfully tested.
  • International comparison measurements in the viscosity range > 100000 mPa·s were carried out for the first time and influences of uncertainties investigated. The uncertainty of the results obtained for highly viscous standard specimens (500000 B) were reduced from 1,3% to 1%.
  • The frequency of a calcium-stabilized laser was determined in a phase-coherent frequency measurement by directly comparing the laser with the primary standard of time and frequency. This phase-coherent frequency measurement of visible radiation was carried out for the first time in the world, and it allowed the frequency uncertainty to be reduced by a factor of 500. At present, this laser thus is the optical frequency standard whose frequency in the visible is known with the greatest accuracy; it makes an improved realization of the unit "meter" possible.
  • In the field of coordinate measuring techniques, one of the most extensive comparison measurements carried out worldwide was concluded in the year under review. A total of 26 laboratories of industrial enterprises, universities and national institutes of metrology from 15 countries participated. The measurement results of about 80% of the participants agreed with the PTB's reference values within the scope of the uncertainty of measurement stipulated for the accreditation as a DKD laboratory.
  • In an investigation conducted over many years, the fine structure constant was redetermined. This fundamental constant of physics is of great importance for quantum electrodynamics, one of the fundamental theories of modern physics. In addition, it is of direct practical importance for the PTB's tasks, as it is used for a more accurate realization of the unit "ohm".
  • In cooperation with the Charité Hospital in Berlin and the Laser Center in Berlin-Steglitz, a measuring method has been developed which substantially improves the early detection of cancer, of intestinal carcinoma in particular. Fluorescence measurements allow cancer cells to be detected already in the microscopic stage and to clearly distinguish them from cellular changes due to acute inflammations.
  • The SOHO space probe (Solar and Heliospheric Observatory) successfully launched from Cape Canaveral on December 2, 1995 carries instruments for the measurement of the solar vacuum-ultraviolet (VUV) radiation, which were calibrated by the PTB by means of the Berlin BESSY I electron storage ring. The calibrations were carried out with great effort and outlay and will allow quantitative results to be derived from the pictures of the sun taken by SOHO. This will contribute to a better understanding of the solar atmosphere and its influence on the earth's atmosphere.

General information

  • In the year under review, work was carried out on a total of five research projects financed by the Federal Ministry of Economics and on 167 projects financed by third parties; non-cash contributions from the Deutsche Forschungsgemeinschaft (DFG, German Research Association) were made use of in 15 cases.
  • In 1995, another 26 DKD calibration laboratories were accredited; one accreditation was withdrawn. Compared with the previous year, the number of accredited laboratories has thus increased by 17%, to a total of 168. Another 23 applications for accreditation have already been filed with the DKD Executive Office.
  • The PTB's research and development work is reflected in almost 560 publications and about 800 lectures. 93 expert meetings and colloquia were held at the PTB.
  • In 1995, the PTB laboratories carried out 8463 calibrations and 11427 tests in about 330 fields, and they granted 113190 approvals in 72 approval categories. Within the framework of comparison measurements prescribed by law, 5186 dosemeters were irradiated, the majority of them with X-rays or photons.
  • The PTB's budget in 1995 amounted to (in million DM):
Personnel costs143,5(139.7)*
Investments in buildings and instruments72,2( 68.0)*
Comsumption expenditure45,6( 44.6)*

*Figures of previous year

The PTB's Press and Information Office has published special Press Releases on particularly important events at PTB. A survey of all Press Releases is given on page 30 of the Annual Report.