Abstract
Along with the development of civilization, lighting technology has been widely used in our daily life resulted more energy consumption as the use of lighting gradually increases. In the advent of solid-state lighting technology, household lightings will soon be replaced by light-emitting diodes gradually. In recent years, in order to comply with utility system specifications, high-voltage LED, abbreviated as HV LED, and alternating-current LED have been developed in the industry. Consequently, lamps and tubes made of LEDs will be directly applied to public lighting systems. Lack of AC/DC conversion units, the systems become more energy efficient. Approximately, energy efficiency will increase in the range of 15 to 30%. The objective of this thesis is to study the optical and electrical properties of HV LED. Firstly, interactions of light-electricity parameters including voltage, current, lumen, color temperature, and color coordinate have been measured. The LED modules under test have exhibited transient heat accumulation and current fluctuation lead to color coordinate displacement. Finally, the displacement of color coordinate measured by integrating sphere has been based on CIE1931 standard with results complying with ANSI Standard. The thesis has concluded stability of the color tolerances (SDCM, Standard Deviation of Color Matching) agreeing with the ANSI Standard.