Patent attributes
Provided is a tunable laser device. The tunable laser device includes a lower clad layer, first to third quantum well patterns disposed on the lower clad layer and arranged in a first direction parallel to a top surface of the lower clad layer, an upper clad layer disposed on the first quantum well pattern, and first grating patterns disposed between the third quantum well pattern and the lower clad layer. The first to third quantum well patterns are arranged in the first direction parallel to a top surface of the lower clad layer, the upper clad layer includes a p-type conductive clad layer, the upper clad layer includes an n-type conductive clad layer, and the third quantum well pattern is electrically intrinsic. When a reverse bias is applied to the upper clad layer, the third quantum well pattern, and the lower clad layer, the third quantum well pattern is changed in refractive index.