Injection seeders are devices that direct the output of small "seed"
into the
Optical cavity of a much larger laser to stabilize the latter's output. Most seed lasers are stable,
monochromatic lasers that emit within the linewidth of the larger laser's gain medium. The single frequency encourages the larger laser to lase in a single longitudinal mode, and the seed laser can also improve the laser's spatial profile and improve the
M squared.
Seed lasers can be
Continuous wave or pulsed. Seeding a pulsed laser can reduce variations in the output energy and timing (
jitter) from pulse to pulse, and smooth out temporal variations within the pulse. Many commercial lasers use a
laser diode as a seeding source.
See also
Bibliography
