What factors affect light distribution?

Question

What will be an ideal response?

Answer 1

The distribution of the light after it has been created in the lamp is affected by three factors: the lamp, reflectors, and lens. Many halogen and all the fluorescent lamps are tubular in shape, thus emitting light in 360 the entire length of the tube. In most cases, a reflector is installed to redirect 50 percent or more of the light. When light is reflected by a surface, there is absorption dependent on the reflectivity of the surface. When selecting a reflector, keep in mind that white has the highest reflectivity. This surface should be cleaned before installation and every time the lamps are replaced. Although the distribution from the other types of lamps is more directed, most likely there will be a reflector to redirect the light in a specific pattern. Lenses are made of clear glass or plastic and are designed to redirect the light. They should be cleaned regularly and replaced if they begin to yellow as is the tendency of some plastics. With most luminaires, charts are available to detail the light distribution. These should be studied to determine whether the luminaire has the proper distribution pattern for the application. For example, a luminaire designed for illuminating book shelves would be a poor choice for an assembly room.