摘要 |
Power control for a laser is performed on at least a per-packet basis, rather than a per-pulse basis, and that end-of-life detection may similarly be performed. This is achieved by accumulating the current generated by a photodiode in response to the light signal generated by the laser, subtracting therefrom a preset threshold current which is similarly modulated in response to the data signal used to drive the laser, and comparing the resulting difference to the value prior to having begun accumulating and subtracting. The result of the comparison, which may be filtered, is used to control the driver of the laser or as an indicator, e.g., for use in end-of-life detection.
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