Анализ цветовых характеристик источников света на базе светоизлучающих диодов в системах динамичного освещения

Abstract

Lighting equipment manufacturers provide the following data that determine the lighting quality: the color temperature (CT), the general color rendering index and the ripple coefficient. However, for a lighting system to be designed in a professional manner, it is necessary to know such parameters as variation of the radiation spectral distribution in the course of operation, the repeatability of characteristics and the influence of environmental conditions on the light device as a whole. All these parameters and characteristics will allow the designer to take into account the specific features of the facility that has to be illuminated. New technologies and new light sources give an impetus for revising the existing lighting standards and rules. Light-emitting diodes (LEDs) are a relatively new, promising and energy-efficient light source, which has a number of unique properties: a long service life, high luminous efficiency, a high color rendering index, aesthetics, environmental friendliness, reliability, high strength and the possibility to control both spectral and integral parameters and characteristics. Owing to the compact size of LEDs, it became possible to make luminaires of various shapes and sizes, and, as a result, of different power and luminous flux. The existing values of luminous efficacy and improvement of the color LED selection (binning) method allow one to speak about the possibility to make a white light source based on color crystals. The use of LED-based light sources in dynamic lighting installations are of great interest for studying them because such light sources open the possibility of dimming the luminous flux and changing the radiation chromaticity independently of each other. Methods of making white LED modules with a variable color temperature (CT) on the basis of two-crystal luminiferous LEDs with different CT and multicrystal LEDs are considered. The accomplished analysis of the data obtained as a result of calculations made it possible to select suitable combinations of LEDs ensuring the best values of the color rendering index and CT repeatability.