摘要 |
Described is a system for measuring, tuning and locking wavelengths of lasers. The system comprises a laser diode that emits a front (or source) laser beam for modulating communication signals and a rear laser beam for sensing and locking the central wavelength of the source laser beam. The rear laser beam is split into a first and a second laser beams. A first adjustable wavelength filter receives the first laser beam at a first incident angle to generate a first reference laser beam, and a second wavelength filter receives the second laser beam at a second incident angle to generate a second reference laser beam. A first photo-detector generates a first reference photo-current in response to the first reference laser beam, and a second photo-detector generates a second reference photo-current in response to the second reference laser beam. The current difference between the first and second reference photo-currents is utilized to measure, tune and lock the central wavelength of the source laser beam. The overall bandwidth or tunable wavelength range within which the central wavelength of a source laser beam can be locked is determined by a filter's incident angle, reflection coefficient and thickness.
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