Patent ID: 7983315

Claim:
A frequency changing device, comprising: a laser which generates light having a specific frequency and which comprises a waveguide in which the light is guided in the laser; and a nonlinear optical medium which changes the frequency of the light generated by the laser, wherein: the laser has an exit facet facing the nonlinear optical medium, from which exit facet the light emerges from the laser, the nonlinear optical medium has an entrance facet facing the laser, through which entrance facet the laser light enters into the nonlinear optical medium, the nonlinear optical medium has at least one exit facet through which the frequency-changed laser light emerges from the nonlinear optical medium, the waveguide of the laser at least adjacent to the exit facet of the laser runs at an angle with respect to the perpendicular to the exit facet, the exit facet of the laser and the entrance facet of the nonlinear optical medium are arranged parallel to one another, the laser is a distributed feedback (DFB) laser comprising a grating which is formed along at least a segment of the laser, the non-linear optical medium comprises a wave guide in which the light is guided in the nonlinear optical medium, wherein the nonlinear optical medium comprises outer edges and wherein the nonlinear optical medium is embodied parallel to the outer edges of the nonlinear optical medium, the entrance facet of the nonlinear optical medium runs beveled at an angle different than 90° with respect to the outer edges of the nonlinear optical medium, and the exit facet of the laser and the entrance facet of the nonlinear optical medium are oriented with respect to one another in such a way that the condition of Snell's law is met; i.e. n laser sin(α laser )= n nonlinear optical medium sin(α nonlinear optical medium ) where: n laser represents the refractive index of the light-guiding region of the laser, n nonlinear optical medium represents the refractive index of the light-guiding region of the nonlinear optical medium, α laser represents the angle between the waveguide of the laser and the perpendicular to the exit facet of the laser, and α nonlinear optical medium represents the angle between the propagation direction of the light in the nonlinear optical medium and the perpendicular to the entrance facet of the nonlinear optical medium.