Investigation of the Ceiling Fixtures Design Evolution and LED Light Bar Alternative Concept Design Formation

Abstract

The purpose of the work is to study the development of concepts and technologies for the manufacture of ceiling fixtures to light the interior of buildings – office, public and administrative ones, etc. It is known that fluorescent lamps have long been used for interior lighting. Massive diffusers made of matte polycarbonate sheets were used to smooth the light intensity curve of such luminaires and bring it to the cosine light distribution. Due to the matte coating of the diffuser, the luminous part of the light fixtures acquired, with a fairly good approximation, the properties of an equally bright surface. Such surfaces are known to have a cosine light distribution and are very convenient for lighting. In the early 2000s, the problem of energy saving worsened, which led to a significant reduction in the number of luminaires of this type. These changes have also affected the approaches to the design of indoor light fixtures. The major difference of the new modifications of fluorescent fixtures is the absence of a matte reflector, which is very uneconomical in terms of energy saving, since it significantly decreased the luminous flux. The refusal to use the diffuser led to the emergence of fluorescent fixtures with a specular reflection system and shutters, which limited the dazzling effect of such lamps. However, with the parallel development of LED technology, the concept of choosing a light source in indoor lighting fixtures began tochange. In grille fixtures, LEDs were gradually replacing fluorescent ones. Nowadays, manufacturers' websites offer a fairly wide selection of LED fixtures. They differ in the price, quality of LEDs used, design and technological solutions. Recently, the volume of production and range of LED light bars has been increasing. The article presents an attempt to consider which fixtures offered on the modern market are the most balanced in terms of engineering solution in the context of lighting, operational, pricing, technological and certification characteristics. Based on the analysis of fixtures of different types and modifications, the authors concluded that the most optimal engineering solution is ceiling LED light bars and developed a method of their design and certification.