Patent ID: 7242026

Claim:
A semiconductor light-emitting device comprising: a semiconductor light-emitting thin film having a first surface and a second surface arranged facing in opposite directions; a first optically reflecting surface disposed on said first surface of said semiconductor light-emitting thin film; and a second optically reflecting surface disposed on said second surface of said semiconductor light-emitting thin film, wherein light generated in said semiconductor light-emitting thin film passes through said first surface and is then emitted, wherein when λ 0 is a center wavelength of light generated in said semiconductor light-emitting thin film, n is a refractive index of said semiconductor light-emitting thin film, h is a thickness of said semiconductor light-emitting thin film, m is 0 or a positive integer, and ξ is a half bandwidth of a light emission spectrum when there is no interference between light rays generated in said semiconductor light-emitting thin film, the thickness h satisfies a following first conditional equation: 0.9 × ( 2 ⁢ m + 1 ) ⁢ λ 0 4 ⁢ n ≦ h ≦ 1.1 × ( 2 ⁢ m + 1 ) ⁢ λ 0 4 ⁢ n and, when m is not 0, m in the first conditional equation satisfies a following second conditional equation: 2 ⁢ m + 1 m ⁡ ( m + 1 ) ⁢ λ 0 2 > ξ .