Laser and optical apparatus including the same

An optical apparatus comprising:

• a source laser configured to generate input seed laser light;
• an amplification element configured to receive the input seed laser light;
• a seed laser configured to provide the seed laser light into the amplification element to generate output laser light,
• wherein the seed laser comprises:
• a pump light source configured to generate pump light;
• a first outer gain medium provided adjacent to the pump light source and configured to obtain a gain of the seed laser light using the pump light;
• a first curved mirror and second curved mirror provided at both sides of the first outer gain medium and configured to reflect the seed laser light into the first outer gain medium;
• a second outer gain medium parallel to the first outer gain medium, and configured to reobtain the gain of the seed laser light reflected by the first curved mirror and the second curved mirror;
• a third curved mirror and fourth curved mirror provided at both sides of the second outer gain medium and configured to reflect the seed laser light into the second outer gain medium;
• and
• an inner gain medium provided between the first outer gain medium and the second outer gain medium and configured to reobtain the gain of the seed laser light.

A laser comprising:

• a pump light source configured to generate pump light;
• a first outer gain medium provided adjacent to the pump light source and configured to obtain a gain of seed laser light using the pump light;
• a first curved mirror and second curved mirror provided at both sides of the first outer gain medium and configured to reflect the seed laser light into the first outer gain medium;
• a second outer gain medium parallel to the first outer gain medium, and configured to reobtain the gain of the seed laser light reflected by the first curved mirror and the second curved mirror;
• a third curved mirror and fourth curved mirror provided at both sides of the second outer gain medium and configured to reflect the seed laser light into the second outer gain medium;
• an inner gain medium provided between the first outer gain medium and the second outer gain medium and configured to reobtain the gain of the seed laser light;
• a first beam splitter between the inner gain medium and the third curved mirror;
• a mode-locking unit provided adjacent to the first beam splitter and configured to generate a pulse of the seed laser light;
• a second beam splitter between the inner gain medium and the first curved mirror;
• and
• an output mirror provided adjacent to the second beam splitter and configured to output the seed laser light outside.