The Academy of Sciences as the cradle of Czechoslovak lasers

The first lasers lit up in Czechoslovakia 60 years ago

Although the first laser amplifier shone in our institute building already in the autumn of 1962, an unfortunate accident with a broken discharge tube delayed the lighting of the Czechoslovak laser by half a year. However, in 1963, lasers of different types were successfully lit up in several laboratories in Czechoslovakia. Solid-state lasers were created almost simultaneously in three places in the spring of 1963: a neodymium laser at the Physical Institute of the Academy of Sciences, a ruby laser at the Research Institute of the Ministry of Defense, and Jan Blabla from our institute even demonstrated his ruby laser to the public at the new planetarium in Stromovka. In the summer, a semiconductor laser followed (Institute of Solid State Physics, now part of the Institute of Physics of the Academy of Sciences), and in the autumn, a gas laser was developed at the Institute of Instrumentation in Brno.

The fundamental impulse for the development of lasers in Czechoslovakia was brought by the educational course "Quantum Radiotechnics", which was organized jointly by the Nuclear and Physical Engineering Faculty of the Czech Technical University in Prague (FJFI) and the Institute of Photonics and Electronics of the Academy of Sciences of the Czech Republic in the hall of our institute in Kobylisy (we wrote about it here).

Let's recall the 60th anniversary of Czechoslovak lasers with memories of Jan Blabla and Viktor Trkal:

... "In the ÚRE-ČSAV (Research Institute of the Academy of Sciences of the Czech Republic), I caught this message with more details in 1961. Thanks to the understanding of the head of the quantum electronics department, RNDr. Viktor Trkal, CSc., I studied the laser technology and, together with two other employees of the department, prepared the implementation of a similar experiment. I contacted Ing. V. Kment, who was involved in growing ruby crystals using the Verneuille method in the Chemical Complex in Ústí nad Labem" (Jan Blabla). In 1962, it was possible to obtain optically very perfect raw material from this workplace and subsequently the first ruby cylinders. We solved the optical perfection of the cylinders thanks to our friendly cooperation with RNDr. Ivan Šolc, CSc. from Monokrystal Turnov. Thanks to a long tradition in the field of precise optical methods and experience in grinding crystals at several workplaces in Turnov, we had several laser cylinders at our disposal the same year. For the reflecting surfaces, we used both vacuum silvering and dielectric thin films in contact with RNDr. Zdeněk Knittl, CSc. from Meopty Přerov.

There were problems with the discharge tube. We obtained only one spiral discharge tube, which unfortunately broke. Thanks to personal contacts that the quantum electronics department had with workers from the Academy of Sciences of the USSR in Moscow in the program of the nitrogen maser, we received several "U" shaped discharge tubes. This led to a change in the technical solution of the laser.

We started testing our laser in the second half of 1962. We had about ten ruby crystals at our disposal, which we gradually replaced and eliminated those that had no chance of success. We also improved the optical quality of the dielectric layers, which often led to significant delays. In addition to increasing the efficiency of transferring optical energy from the discharge tube to the crystal, we also introduced crystal cooling using liquid nitrogen vapor. We observed stimulated emission amplification in the first experiments in 1962, but actual generation did not occur until 1963. In May of that year, we demonstrated laser generation to the public in a packed Planetarium in Stromovka Park in Prague...

Source: Jan Blabla and Viktor Trkal, "The first laser operation on the retina in Czechoslovakia," Fine Mechanics and Optics, pp. 197-198, no. 5-6, 2015.