The war, which was unleashed against Ukraine by the russian federation, clearly highlighted who in the world is a true friend and who is an enemy of our country. The vast majority of the Ukrainian diaspora representatives are definitely among the true friends. Their support, not only material, but also moral, is very important for us. Their positions and voices influence the decisions made by the governments of the countries where they live now, and what it's all about, serve the cause of our future victory. One of our compatriots who sincerely support their people is Eduard Trygubov, a graduate of the Department of Optical and Optoelectronic Devices of the Faculty of Instrumentation Engineering of Kyiv Polytechnic Institute, who currently heads the American company Agema Optics (https://www.agemaoptics.com). This company produces the world's best refracting telescopes for amateur astronomers. Their telescopes have fluorite lenses that provide a clear image with almost no chromatic aberrations (due to which iridescent halos appear at the edges of the image elements). Technical solutions used in telescopes are protected by several US patents owned by Eduard Trygubov and his wife Svitlana, also a graduate of PBF.

The correspondent of "Kyiv Polytechnic" contacted Eduard Trygubov and asked him to answer several questions.

- How did you get to study at Kyiv Polytechnic Institute?

- My path to the Department of Optical and Optoelectronic Devices of Kyiv Polytechnic Institute was quite long, although I became interested in optics back in my school years. At the age of thirteen, I read M.S. Navashin's book "Amateur Astronomer's Telescope" and decided to make a reflector telescope. There was no club where I could do that in Korsun-Shevchenkivskyi, where I lived then. There were no materials and equipment either. My classmate’s older sister, who worked at the Arsenal factory in Kyiv, brought me a piece of optical glass 14 mm thick. I cut a circle with a diameter of 100 mm from it, chamfered it, and, guided by the instructions from the named book, grinded a spherical surface in the glass. To get abrasive for grinding, I atomized grinding disks and divided the powder into fractions. During the work, the mirror was damaged, and I managed to make a fully-featured mirror only in the second year at the university, after I grinded more than a dozen optical surfaces and gained a lot of experience in their manual processing.

Despite my interest in optics, after graduation from school, on the advice of my parents, I decided to enter the Cherkasy branch of Kyiv Polytechnic Institute for the specialty " Instruments of precision mechanics ". But I failed the exams and was called up for military service in a few months.

I served in the air defense command post in moscow, the capital of the soviet union. When I got leave, I visited bookstores and bought books on optics. I read them during night duties. In particular, I bought D.D. Maksutov's new book "Manufacturing and Investigation of Astronomical Optics" (second edition) and while reading it, I finally made my mind up: I would major in optics.

On completing my tour of duty, I successfully passed the entrance exams to the Bauman Moscow Higher Technical School and went home. I traveled by Kyiv, and visited Kyiv Polytechnic Institute. I liked it here more than in moscow, and the main thing is that Kyiv Polytechnic Institute had a Department of Optical and Optoelectronic Devices! I returned to moscow, took my documents, successfully passed the entrance exams and became a student of the Department of Optical and Optoelectronic Devices of the PBF of Kyiv Polytechnic Institute, which was headed by Professor Andriy Ostrovsky at that time.

- How was the studying?

- I really liked studying, because I mastered, one might say, my dream specialty. As I had known a lot even before the institute, it was not difficult to study.

At the same time, due to the fact that I was "one smart apple", I often entered into controversy with lecturers, asked them weighty questions, trying to understand the complex issues of the subjects well. Most of the teachers were quite knowledgeable and experienced, they understood that I was not trying to implode their reputation, but to clear up what was really important to me. And today, I gratefully remember my teachers, such as Serhiy Trokhymovych Koval, Ihor Henrykhovych Chyzh, Borys Pavlovych Kukareka.

From the first days, as soon as I received a library card from the Scientific and Technical Library of Kyiv Polytechnic Institute, I began to study books on optical technology, which had been my biggest miss before. Even now, I recall the cozy reading rooms of the library, where I sometimes spent whole days with warm feelings. In order to learn practical skills better, in the third year I got a job at the Analytprilad plant. I worked after classes - in the second shift. First, I worked in the coating shop, where I made scales for refractometers- saccharometer. Then I worked in the grinding shop. Thus, in practice, I mastered all the main technological processes of manufacturing optical devices. I respectfully remember the head of the optical shop, Anatoliy Andriyovych Tupchienko, and his deputy, Semen Moiseyovych Spektor, who often gave me valuable advice and explained the work techniques specific to each technological section in detail. Later, when I started my company, they helped us more than once to coat optical parts.

In my second year, I met a wonderful person - Volodymyr Semenovych Bohorad, a talented and experienced master optician from the Arsenal plant. He managed the optical club of the factory, where schoolchildren made lenses and mirrors, and also created small telescopes. Volodymyr Semenovych generously shared all his experience and skills. Under his guidance, I mastered the operations of centration and regulating mirrors, and made my first Maksutov telescope.

Thus, by the time I graduated from Kyiv Polytechnic Institute, I knew the theory well and had good practical skills. Later, I learned from my fellow student, who went to Germany, that this is how students were trained for the Carl Zeiss factory. The educational process in combination with constant practice at the base enterprise ensures the training of high-level specialists.

Cooperation with V.S. Bohorad and thesis supervisor S.T. Koval’s recommendations were realized in my diploma project on the topic of an astrograph - a 150-mm Maksutov camera. I not only designed the device, but also manufactured it, and later tried it out – took pictures of a comet with its help. I still have the optics of this device.

- What happened after graduation from Kyiv Polytechnic Institute?

- In 1992, I received a Specialist Diploma and had to search for employment. For some time I worked at the Astronomical Observatory of Kyiv Shevchenko National University, where I worked on the modernization of the meridian circle together with I.P. Naboka, a graduate of the Faculty of Engineering Physics. Later, at the end of the 90s, he and I restored the Double Astrograph Merts-Repsold, manufactured back in 1854. The objective of the telescope was damaged, and we made a new one from scratch. The 254 mm objective was quite unique: I used an aspherical (non-spherical) surface when making the lens. I later used this technique in our apochromatic lenses, which provided high optical characteristics unattainable with the use of conventional spherical surfaces.

In the fall of 1992, I founded a small private enterprise, where I worked with four more employees, and all of us were graduates or students of Kyiv Polytechnic Institute. We bought several broken workbenches from the factories, restored them and began manufacturing elements of optical systems, in particular lenses of a rather large diameter (230-250 mm), spherical and parabolic mirrors, as well as Maksutov meniscus systems.

During one international colloquium on telescope construction held in moscow, we met an amateur who later emigrated to the USA and helped us get the first orders for the manufacturing optical components, in particular, a 315 mm parabolic mirror. As the order was fulfilled with high quality and on time, we received new ones, mainly for manufacturing consumer grade astronomical optics.

We developed production, built a new interferometer for surface control, produced flat autonomously, repaired and manufactured new workbenches. Then, our teacher Borys Pavlovych Kukareka helped us a lot in finding and preparing a room. He also helped us process and ship our first order promptly.

We worked quite successfully for about five years. It would be possible to continue working, but we were fed up with difficulties with the product shipment to US customers. In addition to the fact that it was difficult to make out customs documents, it was necessary to obtain export permits from several other government departments each time.

Therefore, we gradually arrived at a solution: instead of proceeding export documents on products every time, it is necessary to proceed the export documents on equipment once, and move closer to the customers.

In 1998, we placed the equipment in two sea containers and sent it via Odesa to New Orleans. I went myself on a business visa, other employees moved later.

- How did your activities continue in the USA?

CHARA

- We organized a joint company even before moving. Since we had been manufacturing optics for universities for several years and had a certain reputation, soon after moving to the USA we received an order to manufacture auxiliary optics for the CHARA Array High Resolution Interferometer.

The abbreviation CHARA stands for Center for High Angular Resolution Astronomy. The CHARA Array belongs to Georgia State University and is located at the Mount Wilson Observatory, near Los Angeles. It includes six 1-meter telescopes, which are located in a circle 400 meters in diameter. The distance between the telescopes is from 34 to 331 meters. Light rays from telescopes are optically combined in an interferometer that operates at visible and near infrared wavelengths. CHARA CHARA can resolve objects as small as 0.0005 arc seconds at visible wavelengths and 0.0005 arc seconds in the near-infrared (at this angle, a ball one millimeter in diameter is visible from a distance of 412 km). With the help of this instrument, astronomers made a number of discoveries, including the first determination of the diameter of an exoplanet (see https://www.mtwilson.edu/chara).

All the optics used in this interference system to combine the beams of six 1-meter telescopes were to be supplied by our company. We ordered some part of the optics from one of the enterprises (because we did not have large-sized workbenches), and we manufactured all the auxiliary optics for the interferometer itself entirely autonomously.

After that, we manufactured elements of optical systems to the order of universities, as well as consumer grade telescopes for sale. In 1998–2011, approximately 1,000 sets of optics were created, including fluorite and crystal objectives.

In 2012, I quitted that company, and my wife and I decided to start our own, because we had some interesting developments and ideas in our field. We obtained a patent for a new lenticular objective, and improved aspherization technology. On the basis of that patent and other our developments, we manufacture lenses that are better, for example, than the lenses of the well-known company "Carl Zeiss" (unfortunately, they stopped producing astronomical products of this class). We participated in the developments and projects of other companies and universities, and received several more patents. Now there are more than ten of them.

I often come to Ukraine. I was going to organize the production of optics in Ukraine, but in 2014, for obvious reasons, the work had to be stopped.

When I am in Kyiv, I visit my department at Igor Sikorsky Kyiv Polytechnic Institute, and meet members of the Kyiv Astroclub. We communicate a lot on the Internet forum. I am engaged in research on the history of optics. I am also working on the biography of the outstanding optician D.D. Maksutov, who began his scientific career in Odesa.

- What impression did you get from studying at Kyiv Polytechnic Institute?

- My wife and I often look back at our studying at Kyiv Polytechnic Institute, our teachers and fellow students - those were wonderful times. After graduation, we had to visit many educational institutions in different countries, and we can say that the training complex of our university is quite good, and in terms of size, it is probably one of the largest. And its historical part with the restored museum, which we were lucky enough to visit, is a real crown jewel among many universities. While studying, we received a wealth of knowledge, which allowed us to master quite complex optical production independently and achieve good results in our professional career despite difficult times.

- What would you advise current students of Igor Sikorsky Kyiv Polytechnic Institute?

- They say, nobody is born as an engineer, but anybody can become one... In order to achieve something, one should love technology, be interested in the future occupation, constantly learn about new achievements in the field, and only then studying at a technical university will make good sense. If you are not seriously interested in your future major, don't waste your time…

And to those who have really made their mind, I want to wish interesting studies and easy exams! Do not believe the fables that we live in a post-industrial era. Real engineers will always be needed and will always find a decent and interesting job, especially in the post-war period. Good luck, future engineers!

Interviewer V. Mykolayenko