Vintage Table Lamp “PH-Lamp” by PH / Poul Henningsen, Louis Poulsen, 1930s

Poul Henningsen designed the three-shade system back in 1925-1926. The first lights using the system were designed by PH in cooperation with Louis Poulsen for an exhibition in Paris. PH sought to create glare-free light, direct light where it was most needed, and create soft shadows, using incandescent bulbs as a light source. PH 3/2 Table is a member of the three-shade family. Thus PH did not just design a light, but an entire system – around a thousand different models have been produced over the years. PH was the first person to pursue a scientific approach to light and use the logarithmic spiral as a basis. By using a design based on the logarithmic spiral he achieved even distribution of light over the entire curve of the shade. This even light distribution, together with the diffuse reflection through the glass, made it possible to control glare and shadow. Each shade reduces the amount of light equally, due to their distance from the light source. The PH light model numbers refer to the shade size. Each top shade had a corresponding set of middle and lower shades. In the ‘pure’ models, such as the 2/2, the top shade has a size of about 20 cm, with corresponding lower shades. PH 3/2 Table consists of an app. 30 cm top shade, but uses lower shades from the 2/2 model. These ‘hybrid’ models were introduced due to the desire to hang the pendants at lower heights. The system was also used for wall, table and floor lamps. This specific example has a “3,5” top shade (33,7 cm.) and a “2” middle and lower shade making it a “3,5/2 PH lamp”.