Optical System for Led Luminaire

Abstract

Lighting devices are an important element of a large number of technical systems, including road, living, industrial lighting, lighting systems of vehicles. It is known that the light instrument must fulfill two basic lighting tasks: to redistribute the light source of light source in the right way and to limit its dazzling effect. The introduction of light-emitting diodes (LEDs) for lighting necessitated a completely new quality in the construction of luminaires. The different production technology required new methods and designing tools. It also challenged designers with new problems to solve. LEDs are light sources emitting in one hemisphere, which requires a special approach to designing an LED lighting unit. However, for the illumination of premises with high spans or streets, roads such a light distribution is not suitable. For luminaires with solid-state light sources, other materials and new technology must be used; moreover, light distribution needs to be formed using different methods. This paper presents the design process of a LED luminaire from concept to implementation, exemplified by road lighting, and describes the methods and procedures used by the designer. Also, technological problems influencing the quality of the above lighting are addressed. Optical systems for LEDs are considered. The peculiarities of the use of secondary optical elements in the form of lenses for purpose of obtaining different diagrams of the spatial distribution of light intensity of light-emitting diodes are analyzed. Features and problems of calculation of secondary optical systems are considered. Massive collimators do not have to be elements that focus a narrow beam of light. They are able to form a beam in accordance with any accepted distribution that is appropriate for a given application. They are also able to form a beam in a specific way that is required for outdoor lighting luminaires. The stages of a project for designing a road luminaire require the application of the knowledge and experience gained in various research projects. The design methods described in this paper have been developed designing activity and are also to be used successfully in lighting production.