| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a light emitting diode high in output and high in efficiency, excelling in moisture resistance and suitable for a band light emission of 660-720 nm, and a light emitting diode lamp and a lighting system. <P>SOLUTION: The light emitting diode includes a light emitting part, a current diffusion layer formed on the light emitting part, and a functional substrate joined to the current diffusion layer. The light emitting part includes an active layer of quantum well structure formed by alternately laminating well layers expressed by a composition formula (Al<SB>X1</SB>Ga<SB>1-X1</SB>)As (0.20≤X1≤0.36) and barrier layers expressed by a composition formula (Al<SB>X2</SB>Ga<SB>1-X2</SB>)As (0<X2≤1), and a first clad layer and a second clad layer holding the active layer therebetween. The first and second clad layers are expressed by a composition formula (Al<SB>X3</SB>Ga<SB>1-X3</SB>)<SB>Y1</SB>In<SB>1-Y1</SB>P (0≤X3≤1, 0<Y1≤1). The thickness of the well layer is set to 3-30 nm, and a light emission wavelength is set to 660-720 nm. <P>COPYRIGHT: (C)2011,JPO&INPIT |
