Laser diode package

A laser diode package comprising:

• a packaging housing unit;
• a coolant housing unit that is coupled to the packaging housing unit, includes a coolant inlet through which coolant is introduced and a coolant outlet through which the coolant is discharged, and has a coolant flow path therein;
• and
• laser light source units each including a laser diode configured to emit a laser beam, collimating lenses each configured to collimate the laser beam emitted from the laser light source unit, reflective mirrors each configured to reflect the collimated laser beam to an optical element arrangement region on a base, and an optical fiber provided in the optical element arrangement region and in which a stacked beam formed by gathering each laser beam is coupled and emitted to the outside, which are disposed on the base of the packaging housing unit,
• wherein the laser light source unit includes:
• a cooler coupled to the base, including a coolant channel connected to the coolant flow path of the coolant housing unit, and having at least an upper surface made of a metal layer;
• and
• a submount bonding-coupled to the upper surface of the cooler and having an upper surface to which the laser diode is bonding-coupled.