Petzval Joseph Miksa

* Szepesbéla, January 6, 1807 – † Vienna, September 17, 1891 / engineer, mathematician, university professor, external member of the Hungarian Academy of Sciences (1873) ; ; Brother of Ottó Petzval. His father was a teacher. He began his schooling in Késmárk, completed high school in Levoča, and the two-year Royal Academy in Košice (1823–1825). In mathematics – because his teacher considered him weak and because of this his father almost sent him to be a shoemaker’s apprentice – he took a special exam and graduated with honors. Although his native language was German, he later always considered himself Hungarian. He spoke Slovak, Czech, Latin well and learned French and English. Since his father was unable to financially support his further studies, he was tutored by the Almássy family for a year, and the salary he received enabled him to pay the money needed for university enrollment. He received his engineering degree from the Engineering Institute (Institutum Geometricum) of the University of Pest in 1828. He was the city engineer of Pest between 1828 and 1835. In the meantime, he also obtained a doctorate in mathematics. In 1830, he prepared a canalization plan to protect Pest from the floods that threatened it. From 1832, he lectured on mathematics and mechanics at the University of Pest. In 1835, he was appointed professor at the university. In 1836, he was invited by the University of Vienna, where from 1837 to 1877 he primarily lectured on mathematics, but also taught mechanics, celestial mechanics, ballistics, optics and acoustics, as his scientific work also extended to these areas. ; His name was primarily made known by his high-brightness achromatic double photographic lenses, designed in 1840, which reduced the long exposure time (sometimes 5-20 minutes) required up to that time to a fraction of a second. Thanks to this, the daguerreotype also became a commonly used photographic technique. From 1841, the Voigtländer company built its lenses into its machines, which became famous by that time. Peter Friedrich Voigtländer (1812–1878) later abused the fact that Petzval did not patent his invention or conclude a written contract with him, which caused the inventor serious financial losses. According to a note found in his estate, we must also consider him the inventor of the modern anastigmatic lens system. ; As early as 1843, he derived the theorem named after him, which states the formation of an image free of astigmatism (an optical defect). The results of his optical research are his headlamp from 1847, which is the predecessor of the reflectors used in the army, and his scientifically proven finding that incandescent solid bodies emit more light than gases burning with a flame. This principle was used by Carl Auer (1858–1929) in the gas lamp named after him. He was the first to make binocular telescopes. In 1846, he constructed his own laterna magica, which is also called a fog-veil device in Hungarian literature. This was one of the forerunners of modern projectors. In 1856, he created his orthoscope, called the dialite lens, which was a lens used for landscape photography. For this purpose, he also designed a portable, leather-accordioned double-cased optical bench-like camera, which can be considered the ancestor of today's studio cameras. After breaking with the Voigtländer company, he always made the prototypes of his new optical devices himself. Around 1860, he performed photogrammetric measurements with his own machine. The many years of litigation with the Voigtländer company and the unfortunate destruction of his manuscript on the theory of optics discouraged him, and he turned his back on optics for good and began to deal with phonology. In 1869, he married his housekeeper, who died four years later. In 1877 he resigned from his professorship and was awarded the Knight's Cross of the Order of Franz Joseph by the Emperor on this occasion. In his retirement years he became increasingly withdrawn and lonely, largely due to the intrigues of his younger colleagues. Unfortunately, even his heirs designated in his will were unaware of his scientific significance, and as a result, part of his written legacy and many important documents were lost or destroyed. The Petzval Medal, established by the Austrian Minister of Public Education, commemorates his pioneering work in the field of photography. It has been awarded for outstanding achievements in the field of scientific photography since 1928. In his honor, the Optical, Acoustic and Film Technology Association established the Petzval József Memorial Medal in 1962, which is awarded annually. ; ; His main works: ; Bericht über die Ergebnisse einiger dioptrischen Untersuchungen, 1843, ; Eigenschaften einer guten Camera-Obscura, 1847, ; Integration der linearen Differentialgleichungen mit Constanten und variablen Coefficienten (I–II.), 1853–1859, ; Berichte über optische und dioptrische Untersuchungen, 1857, ; Über das neue Landschaft – als Fernobjektiv, 1858, ; Theorie der Störungen der Stützlinien (bei Gewölben und Hängebrücken), 1904–1905, ; Theorie der Tonsysteme, 1904–1905, ; Aus den Vorlesungen über Ballistik. Ein Beitr. zur Geschichte der Ballistik, 1908.