| 摘要 |
PROBLEM TO BE SOLVED: To suppress loss of optical flux from the inside of a semiconductor of a light-emitting element and to effectively guide the light flux once taken out of the element to the outside of a sealed resin. SOLUTION: The surface of a light-emitting element 1 positioned between the light-emitting element 1 and a sealing layer 2 is coated with a thin-film 3 whose refractive index is higher than that of the sealing layer 2, and the surface of the thin-film 3 is given a ruggedness or a rounded shape. Thus, the difference in refractive index is reduced between a semiconductor forming the light-emitting element 1 whose refractive index is very high and the sealing material of sealing layer 2, discouraging total reflection of the light coming out of the semiconductor. Since the light once coming into the thin-film 3 is hard to be totally reflected again on the surface, the light coming out of the light-emitting element 1 is effectively guided outward, for improved efficiency in taking out of light. Since the thin-film 3 also acts as a reflection preventing film, surface reflection is suppressed as well for improved efficiency in taking out of light. |
