Prescription of wavelength-dependent spot size relations of a broadband laser diode in the context of uniformly maximum lens excitation of WDM signals.

We prescribe an empirical relationship between spot size and emitted wavelength for a semiconductor laser diode generating a broad spectrum of light in the near infrared range of 1.5-1.6 µm. Then, we establish uniformly maximum launch optics employing these relations in the case of hyperbolic microlens lens excitation of a step index single-mode fiber using this source. Subsequently, we explain the necessity of this source in the context of wavelength-division multiplexing (WDM) and dense WDM signal transmission with guidelines inviting its fabrication.