PH 4½-3½ Floor Lamp by Louis Poulsen is a glass-shade floor lamp in Poul Henningsen's three-shade family, combining the familiar optical geometry of the PH system with white opal glass shades that introduce translucency and warmth to the floor-standing format. Henningsen developed this system from 1925–26, deriving every shade angle from a logarithmic spiral calculated to eliminate glare and direct light optimally. The glass versions were among the more ambitious iterations — requiring both technical precision in shade geometry and a material that would transmit light softly rather than simply redirect it. The result is a floor lamp that glows gently through its shades while simultaneously projecting a warm downward pool of light.

At 4½ outer shade the PH 4½-3½ Floor Lamp has a generous presence suited to principal positions in a living room — beside a sofa or armchair as a primary ambient light source, or as a centrepiece in an otherwise unlit corner that needs both atmosphere and practicality. The opal glass gives the lamp a softer, more sculptural quality than the metal-shade variants, and it relates naturally to warm, material-rich interior schemes. The combination of downward task-quality light and the gentle luminosity of the glass shades makes it versatile across reading, conversation and atmospheric lighting scenarios.

Architects and interior designers specifying PH glass floor lighting for residential and hospitality projects will find the PH 4½-3½ Floor DWG drawing and CAD block essential for floor-lighting layout and furniture coordination. The 3D model and Revit family support BIM-accurate documentation and IFC-compatible project delivery. A significant and historically grounded specification for projects where authentic PH glass floor lighting is a key design intention.

Available as a 2D DWG drawing, 3D model, Revit file and IFC file.