A lampshade determines how light is distributed in a room, which areas are illuminated, and where shadows are cast. The shape directs the light cone upwards, downwards, or sideways. The material decides whether the light gently penetrates the fabric or only emerges from the openings. When buying a lamp or replacing a shade, it is important to understand how these two factors interact. Only then can one predict whether the lamp is suitable for reading, whether it sufficiently illuminates the dining table, or whether it serves as ambient lighting.
Cylindrical Shades and Their Light Distribution
A cylindrical shade has the same opening at the top and bottom. Light exits evenly from both ends. With opaque fabric, the side wall remains dark; with translucent material, the entire surface glows. A cylinder with a 30 cm diameter and 25 cm height emits a circular light cone upwards and downwards. This shape is suitable for table lamps next to the sofa or on a dresser if you desire indirect light on the ceiling and tabletop. The side wall, if made of opaque fabric, casts a shadow that visually structures the room.
Conical Shades: Wide Base and Narrow Crown
A conical shade tapers upwards. For example, the bottom opening measures 40 cm, while the top is only 20 cm. This creates a wide light cone at the bottom, illuminating a table or work surface. Less light exits at the top, leaving the ceiling darker. This shape is often found in floor lamps placed next to an armchair. The wide bottom edge ensures that books or magazines receive enough light. With translucent fabric, the conical surface itself glows and becomes a visible light source. With dense fabric, it remains dark, and only the openings emit light.
Fabrics and Their Translucency
Linen, cotton, and silk allow different amounts of light to pass through. Densely woven linen with 300 g/m² blocks most of the light, while fine cotton fabric with 120 g/m² allows more to pass. Silk diffuses light softly, creating a warm atmosphere. Synthetic fabrics like polyester can also be translucent, depending on the weave and coating. A black or dark blue fabric allows hardly any light through its surface, while a light beige or white gives off significantly more. To check how much light a shade lets through, hold it against a lit light bulb. If you can see the fabric's structure, the material is translucent. If the surface remains uniformly bright without visible fibers, the material diffuses the light strongly.
Coatings and Linings
Some shades have a white or gold coating on the inside. White reflects light evenly and increases brightness at the openings. Gold or copper tint the light warmly, creating an amber tone. An additional lining of thin fabric dampens the brightness and prevents the light bulb from being visible through the shade. Without a lining, with thin outer fabric, the socket or the shape of the bulb is often visible, which can look cluttered.
Dimensions and Proportions
The size of the shade must match the lamp and the room. A shade with a 50 cm diameter on a 40 cm high table lamp appears balanced. A shade with a 25 cm diameter on a 70 cm high floor lamp looks too small. The table shows common combinations.
| Lamp Height (cm) | Shade Diameter Bottom (cm) | Shade Height (cm) | Application Area |
|---|---|---|---|
| 30–40 | 25–35 | 20–25 | Bedside table, sideboard |
| 50–65 | 35–45 | 25–30 | Side table, console |
| 140–160 | 40–50 | 30–35 | Floor lamp next to armchair |
| 170–190 | 45–55 | 35–40 | Floor lamp next to sofa |
Light Color and Light Source
The light bulb influences how light appears through the shade. An LED with 2700 Kelvin produces warm white light, which appears even warmer through beige or cream-colored fabrics. A bulb with 4000 Kelvin emits neutral white light, which looks cooler through white shades. The wattage determines the brightness: 40 watts (equivalent to about 470 lumens) are sufficient for ambient light, 60 watts (800 lumens) for reading light. A dense shade absorbs about 30 to 50 percent of the light, a translucent one only 10 to 20 percent. If you choose a dark shade, you should use a stronger bulb to achieve the same brightness.
Care and Replacement
Fabric shades attract dust. A soft brush or a duster removes loose particles. For heavier soiling, a slightly damp cloth, gently dabbed over the fabric, can help. Rubbing stretches the fabric and leaves stains. Silk and thin cotton do not tolerate moisture; here, only dry cleaning is an option. A yellowed or damaged shade can often be replaced. Many lamps have a standardized fitting, so you can buy a new shade with a suitable mount. Before purchasing, measure the diameter of the mount and the height of the old shade.
Checklist for Selection
- Shape: Cylinder for even distribution, cone for directed light downwards.
- Fabric: Dense weave for little transmitted light, fine weave for a visible illuminated surface.
- Color: Light tones allow more light through, dark tones dampen and direct light to the openings.
- Inner coating: White for neutral brightness, gold or copper for warm light.
- Size: Shade diameter should be about two-thirds of the lamp height.
- Light source: Adjust light color and brightness to the shade and room.
You can find suitable pieces under Table Lamps and Floor Lamps. Information on how the pieces are constructed, available dimensions, and delivery times can be found on Eichholtz Table Lamps and Eichholtz Floor Lamps.
Frequently Asked Questions
How much light is lost through a lampshade?
A dense fabric absorbs 30 to 50 percent of the light, a fine weave only 10 to 20 percent. The exact amount depends on color, weave, and coating. Hold the shade against a light source to check its translucency.
Which shade is suitable for reading?
A conical shade with a wide bottom opening directs light downwards onto a book or magazine. Choose a light, translucent fabric and a bulb with at least 800 lumens. The lamp should be placed to the side of the armchair, not directly behind it.
Can I replace a lampshade myself?
Yes, if the fitting is standardized. Measure the diameter of the mount on the top ring of the old shade. Common sizes are 4, 6, or 8 cm. Ensure that the new shade has the same mount and fits the height of the lamp base.
Why does a white shade turn yellow over time?
Heat and UV radiation cause light fabrics to yellow. LED light sources generate less heat than incandescent bulbs and slow down this process. Do not place the lamp in direct sunlight, as this accelerates discoloration.