Optical coupling module and manufacturing method thereof having conjoined tapered elements

An optical coupling module, comprising:

• a transmission optical fiber, comprising:
• a center shaft extending along a longitudinal direction;
• a first transmission flat portion;
• a second transmission flat portion;
• and
• a transmission tapered portion, connected between the first transmission flat portion and the second transmission flat portion, wherein an average outer diameter of the transmission tapered portion is less than outer diameters of the first transmission flat portion and the second transmission flat portion respectively;
• and
• at least one pump optical fiber, extending along the longitudinal direction and comprising:
• a pump flat portion, disposed on the first transmission flat portion;
• and
• a pump tapered portion, connected to the pump flat portion, wherein a distance from an outer surface of the pump tapered portion to the center shaft gradually decreases from adjacent to the pump flat portion toward a direction away from the pump flat portion, wherein the pump tapered portion is spliced to the transmission tapered portion, and at a minimum distance from the outer surface of the pump tapered portion to the center shaft, the outer surface of the pump tapered portion has a bonding depth perpendicular to the longitudinal direction with an outer surface of the first transmission flat portion or an outer surface of the second transmission flat portion.