Physicist. Yuri Denisyuk, a Soviet physicist, received notoriety as one of the founders of optical holography. His research publications were limited to the Russian-speaking community, thus isolating his research from the scientific community of Western Europe and the United States. Doing pioneering research in holography, Dennis Gabor, a Hungarian-born English electrical engineer, made his very first fuzzy hologram in 1948 using a light source that consisted of a mercury arc lamp with a narrow-band green filter, one of the best coherent light sources before the 1960 laser. For this discovery, Gabor received the 1971 Nobel Prize, but he abandoned his hologram research after a few years, as he met an unsolvable roadblock. After 1955, holography research went into a period of hibernation. Only after the discovery of the laser in 1960, that the next generation of researchers, which included Denisyuk, advanced in the discovery of the holograph. Initially, Denisyuk had attempted to use the mercury lamp as his source of light, and according to his notes of December 3, 1959, he had some success. His unique but simple single-beam method of making the hologram is called Denisyuk's Hologram. Using the laser, an American engineer Emmett Leith received the credit for being the first to make three-dimensional holography in 1964. Born in Sotchi on the Black Sea, in the Krasnodar Krai, Denisyuk's family relocated to Leningrad when he was a child. As a youth, he experienced during World War II the Siege of Leningrad, an 872-day cruel battle in his hometown with the Nazi army fighting against the Russian army and people. After graduating 7 th in his class, he made plans to enter college. In 1954 he graduated from St. Petersburg Nation Research University at Vavilov State Optical Institute, remaining for 52 years at the institution and making his major discoveries in the field of holography. He published about 240 research papers, which includes 35 inventions. During the last years of his life, he had turned his attention to optical logic, high density data storage and non-linear optics where he also made significant contributions. In 1970 he was awarded the Lenin Prize, which is the highest honor in the USSR, and upon receipt of the prize he was elected to the Academy of Sciences of the USSR. In 1992 he was made a full member of the Academy of Sciences. The Soviet government also awarded him the Order of the Red Banner of Labor in 1988 and the Order of the Badge of Honor in 1975. In 1983, he and Leith were the first recipients of the International Dennis Gabor Award from the Hungarian Academy of Sciences. From Great Britain, he received in 1987 an honorary membership in the Royal Photographic Society along with the Great Silver Medal and an honorary doctorate degree from the University De Monfort. With the fall of the USSR in December of 1991, his research was opened to the Western world, showing the importance of his early research in holography. He received in 1992 the R. W. Wood Prize, which was endowed by the American company Xero and presented by the Optical Society. Considered a brilliant, humble, and generous man, he was a devoted Russian Orthodox Christian. The 372-page "The Art and Science of Holography: A Tribute to Emmett Leith and Yuri Denisyuk" by H. John Caulfield was published in 2004.