日本神戶大學（Kobe University）與日本LED元件製造商優志旺（Ushio）的聯合研究指出，波長為222nm的深紫外線輻射對人體皮膚和眼睛無害，由於波長為222nm的深紫外線僅能到達皮膚的最外層——角質層，所以不會損害皮膚細胞的DNA，有望廣泛用於醫療機構和日常生活等場所的殺菌消毒。[more]   轉載自 LEDinside

AC-driven LEDs (AC LEDs) operate on AC power and may be connected directly to a mains supply without the need of any electronics (e.g. LED drivers or control gears) for converting AC power to a constant direct current. Similar to DC-driven LEDs (DC LEDs), accurate measurements of AC LEDs are also difficult due to the high sensitivity of optical and electrical properties of LEDs to their thermal and operating conditions. In addition, forward voltage, current, and junction temperature of an AC LED change rapidly, which makes measurements even more difficult.

This Technical Report provides guidance for optical measurements of AC LEDs, performed at testing laboratories with emphasis on reproducibility and small measurement uncertainties by accurately setting and controlling the junction temperature. The report includes measurement methods, instrumentation, and procedures. The measurement methods and procedures used for optical measurement of AC LEDs are based on a specified junction temperature using either single AC cycle operation or continuous AC operation.

The publication is written in English, with a short summary in French and German. It consists of 25 pages with 15 figures and is readily available from the CIE Webshop or from the National Committees of the CIE. [more]