Variable CCT constant illuminance white LED light communication system with dimming feature

Integrated system of white LED visible-light communication and power-line communication

Dimming LED Lighting

LED lighting has the potential to offer many benefits to the user and to society as a whole. Very high efficiency together with extremely long life expectancy of the LEDs reduces the energy consumption and the use of resources, and can offer low lifecycle cost. In order to become widely accepted, LED lighting must provide dimming capability at least equivalent to that offered by traditional inc...

Real-time white-light phosphor-LED visible light communication (VLC) with compact size.

In this demonstration, we first demonstrate a real-time phosphor-LED visible light communication (VLC) system with 37 Mbit/s total throughput under a 1.5 m free space transmission length. The transmitter and receiver modules are compact size. Utilizing our proposed pre-equalization technology, the ~1 MHz bandwidth of phosphor LED could be extended to ~12 MHz without using blue filter. Thus, the...

Adaptive Equalization System for Wireless Communication Using White LED

White LEDs were invented the 1990’s. The white LED has lower power consumption, lower voltage requirements, longer lifetime, smaller size, faster response, and cooler operation. We have proposed an indoor visible light wireless communication system that utilizes multiple white LED lighting equipment. In this system, the equipment is used not only for illuminating rooms but also for an optical w...

LED PWM dimming linearity investigation

LED PWM dimming application for large scale LED video displays is analyzed. The need for short light pulse duration is outlined. PWM dimming with short driving pulses is investigated experimentally. The LED response time skew introduces the nonlinearity for PWM dimming. For LED response time skew estimation, a method is suggested that has been successfully applied to measure some of today’s mar...