초록 ▼

A semiconductor light emitting element is disclosed, which is provided with a light emitting region having a diffraction grating formed by periodic corrugations, a modulation region having an external waveguide layer optically connected directly to the light emitting region and a pn junction separat

A semiconductor light emitting element is disclosed, which is provided with a light emitting region having a diffraction grating formed by periodic corrugations, a modulation region having an external waveguide layer optically connected directly to the light emitting region and a pn junction separated from a pn junction of the light emitting region and a window region formed of a semiconductor having a larger energy gap than that of a light emitting layer of the light emitting region and extending from at least one end of the light emitting region and the external waveguide layer. The refractive index of the external waveguide is varied through utilization of the electrooptic effect so that the frequency or phase of light stably oscillating at a single wavelength is precisely controlled or modulated. In particular, when the window region is formed only outside the light emitting region, frequency modulation is carried out, and when the window region is formed at least outside the modulation region, phase modulation takes place.

대표청구항 ▼

In a semiconductor light emitting element having a light emitting region comprising a DFB laser having a substrate, a light emitting layer, periodic corrugations defining a diffraction grating, an a pn junction therein the improvement comprising an external modulation region on the substrate for mod

In a semiconductor light emitting element having a light emitting region comprising a DFB laser having a substrate, a light emitting layer, periodic corrugations defining a diffraction grating, an a pn junction therein the improvement comprising an external modulation region on the substrate for modulating the phase or wavelength of the oscillations of the DFB laser light output having an external light waveguide layer of a larger energy band gap than that of the light emitting layer in direct contact with the DFB laser, a clad layer having a larger energy gap than that of the waveguide layer, a pn junction apart from the pn junction in the DFB laser, an electrode for applying a voltage to the pn junction of the modulation region for varying light output, and at least one semiconductor window region on said substrate at one end of the light emitting element for output of light from the element.