Seed Lasers | <<< | >>> | Feedback |
Definition: lasers which are used for generating some seed light into an amplifier or another laser
A seed laser is a laser the output which is injected into some amplifier or another laser. This is done in, e.g., the following situations:
- A seed laser combined with an amplifier forms a master oscillator power amplifier configuration, used for generating an output with high power. Compared with an approach with a single high-power laser, it is easier to obtain certain features with a low-power seed laser, e.g. single-frequency operation with narrow linewidth, a wide wavelength tuning range or the generation of ultrashort pulses.
- Instead of injection into an amplifier, a single-frequency seed beam can be sent into another laser (slave laser) or into an optical parametric oscillator in order to achieve narrowband emission via injection seeding. It is sometimes possible even to achieve injection locking, where the emitted frequency exactly equals the seed frequency, and the laser noise may be close to that of the seed laser.
Typical types of seed lasers are small laser diodes (single-frequency or gain-switched), short-cavity fiber lasers, and miniature solid-state lasers such as nonplanar ring oscillators (NPROs).
See also: amplifiers, master oscillator power amplifier, slave laser, single-frequency operation, single-frequency lasers, injection locking, injection seeding
