Integrated micro-cylindrical lens with laser diode for single-mode fiber coupling

The integration of a laser diode with a microlens on its emitting surface is introduced in this letter. Calculated results are based on integration of micro-cylindrical lens to laser diode. The lens is directly microfabricated on the emitting surface of the laser diode with operating wavelength 635 nm by focused ion beam (FIB) SiO2 deposition function. The controlled SiO2 deposition process is realized by programming our FIB machine. Using single-mode fiber with core diameter of 10 mu m as testing prototype, coupling efficiency of the compact and miniaturized system reaches as high as 80.1.%, Measured far field angle (full angle) is 2.1 and 31 degrees with and without the lens, respectively.