EMBEDDED HETEROGENEOUS TYPE LASER DIODE

PURPOSE:To obtain a high light output, by making the mixed crystal ratio of an embedded layer larger than the mixed crystal ratio of an active layer so that the difference in the mixed crystal ratio between the active layer and the embedded layer is located within the range of 0.15-0.3. CONSTITUTION:As the mixed crystal ratio difference DELTAx between the active layer 3 and the embedded layer 5 becomes smaller than the vicinity of 0.35, a relative light output increases. When DELTAx reaches the vicinity of 0.15, the light output becomes three times the original output. Meanwhile, a threshold current density is constant when the mixed crystal ratio difference DELTAx is larger than about 0.3, but the density rapidly increases when DELTAx becomes smaller than 0.3. Therefore, when the mixed crystal rato difference DELTAx is made too small, an operating current is increased, and the inherent characteristics of the embedded heterogeneous type laser diode are lost. The desirable range for the mixed crystal difference DELTAx is located in the range of 0.15-0.3, in such a way that the value of the operating current does not become too large and the light output can be improved.