A foam-holding body 52 having a large difference in refractive index between foams 521 and the surrounding material is disposed on the major light extraction surface of the sapphire substrate 50. The foam-holding body 52 has translucency to light of a light-emitting wavelength and is formed of a material such as a silicone or the like, having a refractive index equal to or more than 1.77, and includes a foam-holding layer holding a plurality of foams made of an air or an inactive gas having a refractive index of about one. Therefore, when the light emitted in the light-emitting portion scatters in the foam-holding body 52, the spread of the scattered light becomes wide, which restricts repetition of the total reflection in the light-emitting device to improve an efficiency of the light extraction.

 
Web www.patentalert.com

> Boot for covering ball joint

~ 00368