Alexander Friedrich Just (12 April 1874, in Bremen – 30 May 1937, in Budapest) was an Austro-Hungarian^[1] chemist and inventor.^[2] Later, in Hungary he used the name Just Sándor Frigyes. In 1904 with Austro-Hungarian Franjo Hanaman he was the first to develop and patent an incandescent light bulb with a tungsten filament, made by extruding a paste of tungsten powder and a carbonaceous binder to produce a fine thread, then removing the carbon by heating in an atmosphere of hydrogen and water vapors.^[3] Just and Hanaman received a Hungarian patent in 1904, and later US Patent 1,018,502.^[1] In 1905, Just and Hanaman patented a process for producing tungsten filaments by plating carbon filaments with tungsten, then removing the carbon by heating.^[4] These early tungsten lamps were more efficient than a carbon filament lamp, because they could operate at a high temperature, due to the high melting point of tungsten. The tungsten was, however, so brittle that these lamps were of limited practical use.^[5] It was supplanted by the drawn tungsten filament lamp, developed in 1910 by William David Coolidge.