Abstract: A multi-frequency laser system including a first beam splitter configured to split the first beam into a high-power portion of the first beam and a low power portion of the first beam and a second beam splitter configured to split the second beam into a high-power portion of the second beam and a low power portion of the second beam, wherein a frequency of the first beam is shifted with respect to a frequency of the second beam. The system includes a combiner configured to combine the low power portion of the first beam and the low power portion of the second beam to generate a heterodyne beam used to reduce a phase error between the high-power portion of the first beam and the high-power portion of the second beam.

Abstract: Method and apparatus are disclosed that enable lasers to be stabilized in absolute frequency to high precision. The principle of operation is to: 1) lock the laser frequency to an etalon transmission resonance, 2) phase modulate the laser beam at a frequency corresponding to the free spectral range of the etalon and lock the phase modulated sidebands to the etalon resonances, and 3) lock the etalon free spectral range frequency to a stable reference frequency derived from, e.g., a stable crystal oscillator. The result is that the laser frequency is locked to an integer multiple of the reference frequency. The invention has applicability to numerous situations where a stable frequency must be provided at a specific value, and has further applicability to stabilizing multiple lasers in different locations to the same value.

Abstract: Method and apparatus are disclosed that enable lasers to be stabilized in frequency to a high precision while simultaneously enabling rapid re-acquisition of stabilization control loops in the event of frequency locking loss. The principle of operation is to incorporate two etalons, one having a high finesse for frequency high stability, and one having a low finesse for wide error signal locking range, and electronics that pass control between two control systems in such a manner that any loss of frequency locking is rapidly re-acquired.

Abstract: Method and apparatus are disclosed that enable lasers to be stabilized in absolute frequency to high precision. The principle of operation is to: 1) lock the laser frequency to an etalon transmission resonance, 2) phase modulate the laser beam at a frequency corresponding to the free spectral range of the etalon and lock the phase modulated sidebands to the etalon resonances, and 3) lock the etalon free spectral range frequency to a stable reference frequency derived from, e.g., a stable crystal oscillator. The result is that the laser frequency is locked to an integer multiple of the reference frequency. The invention has applicability to numerous situations where a stable frequency must be provided at a specific value, and has further applicability to stabilizing multiple lasers in different locations to the same value.

Abstract: Method and apparatus are disclosed that enable lasers to be stabilized in frequency to a high precision while simultaneously enabling rapid re-acquisition of stabilization control loops in the event of frequency locking loss. The principle of operation is to incorporate two etalons, one having a high finesse for frequency high stability, and one having a low finesse for wide error signal locking range, and electronics that pass control between two control systems in such a manner that any loss of frequency locking is rapidly re-acquired.