Exactly one can not speak of the inventor or the exact time of the discovery of the light bulb. In the early years filaments were used. These were some charred strips of paper, which didn't last very long. In 1913 the American, Irving Langmuir placed within bulbs nitrogen and argon for slower evaporation. In 1934 was began the use the filament which was doubly coiled. This gave rise to the current bulbs and there are a lot of patterns and shapes.