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) SiO 2 deposition function. The controlled SiO 2 deposition process is realized by programming our FIB machine. Using single-mode fiber with core diameter of 10 μm 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/spl deg/ with and without the lens, respectively.