Louis Poulsen 🇩🇰 PH4/3 Metal Table Lamp

Lampe de table PH4/3 Louis Poulsen – Poul Henningsen, 1925

The PH4/3 table lamp is a member of the three-shade family which numbers 30 lights today, including three for outdoor use. The number 4 of PH4/3 name refers to the 40cm of the top shade. Like any model of the PH series, the ratio of the tree lampshades allows an optimal and non-energy consuming distribution of the light.

PH 4/3 Table Lamp

Dimensions Ø45 cm, height 54cm

Light source 1 x E27

Shades spun aluminium

Base and stem high lustre chrome plated

Mounting cord with plug length 2.9 m – in-line switch on cord

Weight 2.3 kg

Class Ingress protection IP20. Electric shock protection II w/o ground.

In 1926, Poul Henningsen said: "The real innovation of the PH luminaire is that it produces light that is both glare-free and economical. It is quite easy to create glare-free lighting (indirect light or with a thick shade) if a portion of the light can be wasted. It's also easy to create highly efficient luminaires if you ignore the fact that they are highly irritating to the eyes. But achieving lighting that is both economical and glare-free is an art.

As early as 1925, Poul Henningsen came up with the idea of using a logarithmic spiral to control the brightness and nuance of luminous light, with each shade equally reducing the amount of light emitted as a function of distance from the bulb. The transitions in brightness between each shade were harmonic, and the relative size of the shades and their positioning were determined by the need to reduce glare, the arrangement of the light and the need for light distribution, according to some remarkably simple principles. The concept was extremely flexible: not only was it possible to achieve different sizes, but also to shape the light with white, silver or gold surfaces. Poul Henningsen imagined that in a restaurant the light should be warm and intimate, and that a golden surface should be used, unlike in a hospital where white surfaces should be used.

The first luminaires were all made with metal shades, then Poul Henningsen developed a variant in opal glass with a sandblasted lower section. The shades let 12% of the light through and contributed to the ambient lighting of the room, while most of the light was reflected downwards. For the pendant lamps, the sizes of the 3 shades were in a ratio of approximately 3:2:1. For table lamps, the lower shades had to be smaller. This gave rise to the PH 2/1 and PH 3/2 ratios.

Poul Henningsen

Born in Copenhagen, Poul Henningsen's mother was the famous Danish actress Agnes Henningsen. He never qualified as an architect, but studied at the Technical School in Frederiksberg (Denmark) from 1911 to 1914, and then at the Technical College in Copenhagen (1914-1917).

He started out practising traditional functionalist architecture, but over the years his professional interests evolved to focus mainly on lighting, which is what he is most famous for. He also branched out into writing, becoming a journalist and author. For a brief period at the start of the Second World War, he was chief architect of Tivoli Gardens in Copenhagen. But like many other creative people, he was forced to flee Denmark during the German occupation, and soon became a vital part of the Danish colony of artists living in Sweden.

His long collaboration with Louis Poulsen began in 1925 and lasted until his death. To this day, Louis Poulsen still benefits from his genius. Poul Henningsen was also the first editor-in-chief of the business magazine "NYT". Louis Poulsen's CEO at the time, Sophus Kaastrup-Olsen, offered PH the magazine because he had been sacked from the Danish newspaper he was working for (his views were too radical).

Poul Henningsen's pioneering work on the relationship between light structures, shadows, glare and colour reproduction, compared with man's need for light, remains the foundation of the lighting theories still practised by Louis Poulsen.