Investigation of phosphor compositions for led filament bulb

Abstract

The paper describes the results of research and development of a phosphor composition for an LED filament. Phosphoric composition is designed to produce white-colored glow of LEDs and LED strands. It consists of both phosphor particles and a binder based on an optically transparent compound. Investigations of the chemical composition, the size of the phosphor particles, the refractive index of the phosphor compositions, the dependence of the correlated color temperature on the ambient temperature are determined. The light-emitting diodes were made on the basis of the investigated phosphor compositions, the luminous efficacy value was 193 lm/W with the correlated color temperature of 5960 K. As a result of studies of the effect of ambient temperature on phosphor compositions, it was established that on all samples of the phosphor composition the correlated color temperature rises with the ambient temperature medium from +25°C to +125°C an average of 2500 K. The results of the research extend to LEDs, LED matrixes and LED strands of white glow.