The light-emitting device 1 has a translucent cover 10 having a cylindrical shape and a flat light-projecting surface 11 facing to the light-emitting part of an LED 20. The LED 20 is arranged in close proximity with the flat light-projecring surface 11 in the translucent cover 10 to achieve efficient introduction of light from the LED 20 into a lig ht-receiving surface of optical fibers.發光裝置(1)具有有圓柱形形狀的透光蓋件(10)、及面對LED(20)的發光部份的平坦的光投射表面(11)。LED(20)係與平坦的光投射表面(11)緊密接近地被配置在透光蓋件(10)內,以達成將來自LED(20)的光有效率地引入光纖的光接收表面內。1‧‧‧發光裝置10‧‧‧透光蓋件11‧‧‧端面(光投射表面)20‧‧‧LED(發光二極體)21‧‧‧LED晶片(發光元件)22‧‧‧基板30‧‧‧電極機構31‧‧‧陰極端子(負電極)312‧‧‧較小直徑區段316‧‧‧較大直徑區段317‧‧‧開口32‧‧‧陽極端子(正電極)33‧‧‧端子支撐件
