| Abstract: | Embodiments relate to an all fiber passively Q-switched laser. The laser
includes a large core doped gain fiber having a first end. The large core
doped gain fiber has a first core diameter. The laser includes a doped
single mode fiber (saturable absorber) having a second core diameter that
is smaller than the first core diameter. The laser includes a mode
transformer positioned between a second end of the large core doped gain
fiber and a first end of the single mode fiber. The mode transformer has
a core diameter that transitions from the first core diameter to the
second core diameter and filters out light modes not supported by the
doped single mode fiber. The laser includes a laser cavity formed between
a first reflector positioned adjacent the large core doped gain fiber and
a second reflector positioned adjacent the doped single mode fiber. |