High Brightness Small Core Diameter Laser Diode Fiber-Coupled Module

Along with the wide application of semiconductor laser in pump laser, plastic material welding, medical, marking, night vision, guidance and other areas. Its requirements on beam quality, power density, brightness are more and more needed. Beam quality can be improved greatly by LD and fiber coupling. First it will make the spot rounded to meet and join up subsequent optical system and easy to use. Secondly the beam occurs more than three thousand times total reflection within a certain distance of the fiber, Eliminate dark spots and faint dots to make the beam homogenization. Two or more single emitter diode laser combination can achieve the high brightness, the power density can be increased by using a small core diameter optical fiber output.In this paper, Hyperboloid lens are used for collimation in fast and slow axes, the beam divergence angle are compressed effectively. The backlighting road of PBS be used for combining the two orthogonal beams which have high linear polarization. According to the focus conditions we know that there is an intersection of the focal length in both directions, which is of the same focal length lens can be used for fast or slow axis beam focusing. Non-spherical lens of7mm focal length has been choosen, simulation results show that the beam can enter into50um of fiber have been met. AuSn solder is used to weld chip and copper heat sink. Using F-mount for packing. Taking into the large different between the CTE of copper heat sink and chip, CuW is used as transition of heat sink. The output power can achieve11.2W, and total coupling efficiencies are over80%at operation currents of7.2A.