Light Distribution Patterns

The Illumination Engineering Society (IES) writes many of the industry standard specifications for fixtures. The IES has designated several standard types based on their light distribution patterns. Figure 5-2 shows plan views of light distribution patterns for the basic types of conventional luminaires. TxDOT standard roadway luminaires are typically IES Type II or Type III.
Plan views of light distribution patternsfor basic types of conventional luminaires. (click in image to see full-size image)
Figure 5-2. Plan views of light distribution patterns for basic types of conventional luminaires.