Visible light communication (VLC) is an optical wireless communication technology that uses low-power light-emitting diodes (LEDs) to not only provide light, but also broadcast data [1–3]. LEDs are extremely energy-efficient and are expected to become widespread in general lighting applications. Because LEDs are solid-state lighting devices, they can be modulated at high speed compared to other...

In this study, to achieve the constant current drive and brightness control without a separate pulse width modulation (PWM) converter, a single converter is designed and verified by experiment under the condition of a multiple LED light load with different output voltage (Vf) characteristics. In the case of the input of 140 Watt class level, the proposed converter can drive two voltage type 95 ...

Aim The aim of this study is to compare and to evaluate effect of curing light and curing modes on the nanohybrid composite resins with conventional Bis-GMA and novel tricyclodecane (TCD) monomers. Methodology Two nanohybrid composites, IPS empress direct and charisma diamond were used in this study. Light-emitting diode (LED)-curing unit and quartz-tungsten-halogen (QTH)-curing unit which we...

Colour harmony plays an important role in fine arts, architecture and design. But it can be also important to describe the quality of light sources: the distortion of perceived colour harmony of a set of colour samples under a light source can be a relevant factor by ranking the perceived colour quality of different light sources. In an earlier experimental study[1], we came to the conclusion t...