| 摘要 |
<p>An apparatus including a gain chip 11, an optical frequency selecting element 16, an actuator 15 and actuator driver 31; the optical frequency selective element returns (i.e. reflects, diffracts) light leaving the gain chip in a band of wavelengths back to the gain chip; the optical frequency selective element is characterized by an angle relative to light leaving the gain chip and distance from the gain chip, the angle and distance are controlled by the actuator; part of the diffracted light is amplified by the gain chip; the actuator driver causes the angle to be dithered about an equilibrium angle in a motion characterized by an amplitude and average frequency. The amplitude of the dithering motion is chosen to either excite a plurality of adjacent laser modes of the gain chip or provide a servo signal for maintaining the grating angle at a target value. The optical frequency selective element may be a grating, a prism or a mirror. The apparatus may be an external cavity laser.</p> |
