Wavelength tunable external resonator laser using optical deflector

A wavelength tunable external resonator capable of tuning a wavelength using an electrical signal, comprises:

• a light source for emitting beams of the plurality of wavelengths;
• a lens for making the beams in parallel;
• a diffraction grating for diffracting incident beams;
• a reflection mirror for reflecting incident beams;
• and
• an optical deflector positioned between said lens and the diffraction grating, for changing the direction of the parallel beams incident on said diffraction grating by controlling the refractive index of the optical deflector depending on an application of the electrical signal, and then making beams of a specific wavelength propagate perpendicularly to said reflection mirror,
• wherein beams perpendicularly reflected by said reflection mirror are focused on said light sources
• and wherein said optical deflector comprises a slab waveguide and a triangle shape portion of a p/n junction in the slab waveguide, wherein if a beam traveling through the slab waveguide passes through the triangle shape portion of the p/n junction, a refractive angle of the beam is controlled by variations in the refractive index, depending on variations in the density of a carrier in the slab waveguide by injection of current or application of voltage into/to the p/n junction.

A wavelength tunable external resonator capable of tuning a wavelength using an electrical signal, comprises:

• a light source for emitting beams of various wavelengths;
• a diffraction grating of a concave shape for diffracting the emitted light to a parallel light;
• a reflection mirror for reflecting the incident beams;
• a lens for focusing the beams incident in parallel in the diffraction grating of the concave shape on an optical fiber;
• and
• an optical deflector positioned between said diffraction grating of the concave shape and said reflection mirror, for changing the direction of parallel incident beams from the diffraction grating by controlling the refractive index of the optical deflector depending on the application of the electric signal, and then making a beam of a specific wavelength propagate perpendicularly to the reflection mirror,
• wherein the beams perpendicularly reflected by said reflection mirror are focused on said source,
• and wherein said optical deflector comprises a slab waveguide and a triangle shape portion of a p/n junction in the slab waveguide, wherein if a beam traveling through the slab waveguide passes through the triangle shape portion of the p/n junction, a refractive angle of the beam is controlled by variations in the refractive index, depending on variations in the density of a carrier in the slab waveguide by injection of current or application of voltage into/to the p/n junction.

A wavelength tunable external resonator capable of tuning a wavelength using an electrical signal, comprises:

• a light source for emitting beams of a plurality of wavelengths;
• a lens for making the beams in parallel;
• a diffraction grating for diffracting incident beams;
• and
• an optical deflector positioned between said lens and the diffraction grating, for changing the direction of the parallel beams by controlling a refractive index of the optical deflector depending on an application of the electric signal, and then making beams of a specific wavelength diffracted by the diffraction grating returned parallel to the lens in an opposite direction,
• wherein the beams of a specific wavelength returned parallel to the lens in the opposite direction are focused,
• and wherein said optical deflector comprises a slab waveguide and a triangle shape portion of a p/n junction in the slab waveguide, wherein if a beam traveling through the slab waveguide passes through the triangle shape portion of the p/n junction, a refractive angle or the beam is controlled by variations in the refractive index, depending on variations in the density of a carrier in the slab waveguide by injection of current or application of voltage into/to the p/n junction.