PH. You do not need more information other than these renowned initials to recognize the celebrated trademark of Danish architect and lighting designer Poul Henningsen (1894-1967), a man who played a crucial role in the evolution of lighting design.
Poul Henningsen was a prominent figure of his time – not just in the world of design, but he also achieved great influence through his authorship. He was known as a progressive thinker, not shy of expressing his opinions. He was particularly vocal about his beliefs on the necessity to combine art and technique in order to improve design. This symbiosis is manifested in his lamp design where aesthetics and function are always equally represented.

His light-experiments in collaboration with lighting manufacturer Louis Poulsen led to the construction of the iconic PH lamp, which demonstrates a paradigm shift in the evolution of modern lighting. PH was one of the first to apply a scientific understanding of light in his designs. From the very beginning of his profession, he strived to create a unique, technical construction that could present the perfect glare-free light.
In 1925-26 he realized that for him to control the direction of the light, he needed to incorporate the concept of the logarithmic spiral to the curvature of his lampshades. During this time he was assigned to provide lighting for the newly constructed Forum Exhibition Hall in Copenhagen. This resulted in his classic three-shade construction where each shade is made to equally distribute the amount of light reflected.

The three-shade design is not simply an example of great lighting. The logarithmic composition of the three shades is also bound to the principles of The Golden Ratio. When Poul Henningsen applied these principles to his design he achieved an organic, balanced and visually pleasing composition. The PH lamp is therefore one of the greatest examples of how technical excellence should not compromise the aesthetic appearance.
Henningsen had now accomplished the glare-free light. His eminent design became an instant success resulting in an extensive system of three-shade lamps. The system extended in different sizes, colors and materials and finally the pendulum lamp was accompanied by table lamps, floor lamps and wall-mounted lamps – so that the glare-free light could be appreciated everywhere.

Poul Henningsen ultimately changed our perception of light and almost 100 years after the lamp’s first introduction at Forum, the PH lamp still stands as one of the greatest designs of all time.

Poul Henningsen in his office, c. 1930