A beam spreading device for use with a centralized lighting system and which can be applied to emergency vehicle lighting applications achieves a beam pattern light output which is essentially continuous over an output range of plus and minus 45 degrees from a center point. The beam pattern light output also has a predefined height associated therewith. The beam spreading device is constructed so as to have a curved surface which mixes the light travelling therethrough so as to achieve the continuous light output. Side wall surfaces of the beam spreading device provide for total internal reflectance properties of the beam spreading device. In one embodiment, a color wheel can be interposed between the output of optical fibers which transmit the light from the centralized light source to the necessary remote location, and the beam spreading device. The color wheel provides the ability to generate different color light outputs from a single light source. In another embodiment, the side wall portions are curved to enable significant packaging depth advantages.