Manufacturer: Louis Poulsen | Designer: Poul Henningsen

Poul Henningsen developed his three-shade system in 1925–1926, first realised in cooperation with Louis Poulsen for the Paris Exhibition. Built on the logarithmic spiral, the system positions the light source at the focal point of the curve, with every shade angle calculated to redirect and soften the output of the bulb — eliminating glare and directing the majority of light downward. Glass was introduced to the three-shade family to extend the system’s reach: where metal shades direct light downward, glass shades also illuminate the surrounding room, filling the space with a soft, diffused glow. The PH 4½-3½ Glass Table Lamp was introduced in its current form in 1990. It is a hybrid model — an approximately 450mm top shade paired with lower shades from the 3½ scale, a proportion first developed to bring pendants to lower heights and later adapted for table use.

Three mouth-blown three-layer white opal glass shades — glossy on the exterior, sandblasted matt on the underside — produce a harmonious, glare-free light distribution both downward and into the room. A purple spun aluminium anti-glare ring at the base of the fixture controls the view of the light source from below. The top plate, base and stem are high lustre chrome plated brass and steel. The on/off switch is integrated into the lamp base.

• Light source: Max 1 × 100W E27 (not included)
• Shades: Mouth-blown three-layer white opal glass, glossy exterior / sandblasted matt underside
• Anti-glare ring: Purple spun aluminium
• Top plate & base: High lustre chrome plated spun brass
• Stem: High lustre chrome plated steel
• Cord: 2.7m black plastic with plug | Switch in lamp base
  
• Weight: Max. 9kg
• IP20

Also available as the PH 4½-3½ Glass Floor Lamp. Part of the Louis Poulsen PH Lights collection.