Light-emitting diodes (LEDs) are a relatively old technology (1970s) that has
advanced from use in numeric displays and indicator lights to a range of new and potential new applications, including exit signs, accent lights, task lights, traffic lights, signage, cove lighting, wall sconces, outdoor lighting and downlighting.
LEDs offer benefits such as small size, long lamp life, low heat output, energy savings and durability. They also allow extraordinary design flexibility in color changing, dimming and distribution by combining these small units into desired shapes, colors, sizes and lumen packages. Currently, relatively low overall light output, poor color rendering and questions about advertised service life may indicate that LEDs, while very useful in many applications, are not yet ready for “prime time” in some architectural applications. Notably promising current applications include retail display, colored lighting, tight spaces, areas that require low light levels, exterior lighting and applications where the integration of light sources and architectural elements is critical.
LEDs currently dominate the exit sign market and many cities have adopted them as a replacement for incandescent lamps in traffic signals. In the architectural market, the development of a visible/white light LED has awakened lighting designers to new possibilities with this light source. White light LEDs, however, currently do not produce enough lumen output to make them competitive with many general light sources. This restricts their use in architectural projects to applications where small lumen packages are needed and where the characteristics of a lower CRI rating and high color temperature are acceptable.
