Prof. Rudolf Berthold

Prof. Dr. Rudolf Berthold

Professor Dr. Rudolf Berthold was born on May 22, 1898 in Stuttgart, where he also attended school and studied electrical engineering. During his doctoral studies, he specialized in X-ray technology.

After his first job with Koch and Sterzel in Dresden, he joined Siemens in Berlin. He married his wife Johanna in 1927. The family grew - first with their first son, Fritz, in 1929, and finally with their second son, Hans, who was born in 1932.

In 1933, he founded the Röntgenstelle, a private company that operated out of the State Materials Testing Institute in Berlin-Dahlem. As part of the expansion of the autobahn system, the steel structures of the autobahn bridges had to be inspected regularly. However, Rudolf Berthold's employer at the time, Siemens, did not have the necessary expertise as a manufacturer of X-ray equipment.

This gave Rudolf Berthold the opportunity to perform non-destructive testing of welds on steel structures on behalf of the state. After receiving the state inspection seal, the Röntgenstelle was renamed the "Reichsröntgenstelle", but remained legally and financially independent. Today, it can best be compared with the technical inspection associations, which are financed as service companies through inspection fees or the sealing of third-party inspections.

The weld inspection process used an X-ray tube and X-ray film as a detector and was usually performed overnight because the films were very insensitive. Rudolf Berthold eventually came up with the idea of replacing the film with the much more sensitive counting tube that Geiger and Müller had developed in the early 1920s to detect ionizing particles.

In 1936, he brought a specialist for self-extinguishing counting tubes from Stuttgart, Dr. Adolf Trost, to Berlin for the development.  Soon afterwards, device development within the Reichsröntgenstelle was transferred to the "Four-Year Plan Institute". By separating the testing and development institute, it was possible to participate in the general state research funding. One result of the Four-Year Plan Institute's development program was the first counting tube for level measurement.

In the meantime, Rudolf Berthold had also received a teaching position and eventually a professorship at the TH Berlin. During the war, however, the buildings of the Reichsröntgenstelle and the Vierjahresplaninstitut burnt down in 1943 after a bombing raid.  Fortunately, important equipment and documents were saved from the burning building.

Rudolf Berthold is able to continue the Reichsröntgenstelle and moves it to his private home in Berlin-Wannsee. The Four-Year Plan Institute, on the other hand, is relocated to Neuenbürg in the Black Forest to the former Hotel Bären under the management of Dr. Trost. Mrs. Berthold and her children also leave Berlin and move to Wildbad. Professor Berthold finally follows them in 1945.

After the war, much of the Black Forest came under French administration and the equipment of the Four-Year Plan Institute was confiscated.  Like almost everywhere in Germany, the first few years are very difficult for Berthold and his small team and are characterized by mutual support and an almost family-like cohesion among the staff.

However, through contacts with the French authorities, Berthold finally succeeded in repossessing the confiscated equipment, whereupon he founded a trading company, the "Laboratorium Professor Dr. Berthold".  As the premises in Neuenbürg had become too small, the company was relocated from Neuenbürg to Wildbad in the spring of 1949 to the premises of the former inn "Zum Kühlen Brunnen".

In 1949, 5 workers, 2 employees and 2 apprentices worked alongside Prof. Berthold in the "Laboratorium Professor Dr. Berthold".  The range of applications of radiation measurement technology grew - level gauges, X-ray goniometers, a wire rope testing device, measuring devices for testing coating thicknesses, but also radiation measuring devices for general applications in the radium-processing industry, research and medicine.

In the mid-1950s, Berthold built the first density meters. In some applications, the more sensitive scintillation counters replaced the counting tubes used until then. Berthold also began working with Kernreaktor Bau- und Betriebsgesellschaft, the forerunner of the Karlsruhe Nuclear Research Center.

Berthold was not only a pioneer of material testing, but also an enthusiastic cellist. Here he followed the tradition of his father, who was a solo cellist at the Stuttgart State Theater. A tradition that even the employees could not escape: Christmas dinner always began with a "compulsory musical education" with a prelude by the company's own string quartet (Prof. Dr. Berthold, cello; Alfred Trippner, violin; Fritz Berthold, viola; Robert Schlegel, flute).

Prof. Dr. Berthold died in January 1960 and was active for his company until the end. However, his pioneering work in the field of non-destructive material testing is still honored today at the Federal Institute for Materials Testing in Berlin, where the "Berthold House" bears his name.

Dr. Adolf Trost

Dr. Adolf Trost

Dr. Adolf Trost was born in 1911 in Stuttgart, Germany. He studied physics there and later developed the self-extinguishing Geiger-Müller counting tube.

While working on his Ph.D., he noticed that counting tubes worked more reliably and effectively if the tube was not pumped clean after the last cleaning with alcohol. After experimenting with various vapor additives and internal tube surfaces, he finally succeeded in developing the internally quenching Geiger-Müller counting tube.

Dr. Trost moved to the Reich X-Ray Center in 1936 and remained there until the evacuation of the "Four-Year Plan Institute" to Neuenbürg in 1943.

He remained with Berthold for the rest of his working life until 1980 as head of development for radiation measuring devices.

Dr. Fritz Berthold

Dr. Fritz Berthold was born in Berlin in 1929. During the war, he moved with his mother and brother Hans from Berlin to Wildbad as a result of the order for women and children to leave the capital. His father Prof. Dr. Rudolf Berthold followed them in 1945.

He first went to school in Wildbad, then in Pforzheim. His father's colleague, Dr. Adolf Trost, helped him catch up on physics and mathematics lessons he had missed during the war. When the Pforzheim grammar school was destroyed in a bombing raid, Fritz Berthold moved to Stuttgart, where he stayed with his grandfather. Here he also experienced the end of the war, met American soldiers and learned American English.

Immediately after graduating from high school, he received a scholarship and studied in North Carolina for 9 months. He then spent the rest of the year hitchhiking around the USA.

He then continued his physics studies in Stuttgart, Durham N.C. (USA). Mainz and Freiburg and became a graduate physicist. He finally received his doctorate in Freiburg in 1957.

Dr. Fritz Berthold (young)

In 1960, he was actually planning to go to the USA for 2 more years for a scientific project, but broke off his stay at Stanford prematurely when his father died. Instead of continuing his scientific career, he accepted the challenge of taking over his father's legacy and managing the group of companies as Managing Director and Head of the Development Department.

In 1967, he founded the "Radiation Protection" division and subsequently the "Bioanalytics" division. Berthold becomes the gold standard in luminescence measurement technology. Under the leadership of Dr. Fritz Berthold, the company grows from a turnover of DM 1.5 million in 1960 to DM 80 million in 1989.

In 1989 he sold the company to the American technology group "EG&G", now Perkin Elmer. After 11 "Perkin Elmer years", he decided to buy the company back in 2000 together with the Berthold family and Hans J. Oberhofer and to continue the business under the name Berthold Technologies GmbH & Co KG.

24 years later, Dr. Fritz Berthold still supports the company. He is a member of the advisory board and senior partner.