Abstract: Calibration of laser pulse powers used to form subsurface optical structures in an ophthalmic lens is accomplished via generation of a feedback signal indicative of pulse energy absorption. A system for forming subsurface optical structures within an ophthalmic lens includes a laser pulse source, a laser pulse power control assembly, a scanning assembly, a detector, and a control unit. The laser pulse power control assembly is operable to selectively control an energy of respective laser pulses. The detector is configured to generate a feedback signal indicative of an energy absorbed by the ophthalmic lens from a first laser pulse. The control unit is configured to control operation of the laser pulse power control assembly to selectively control an energy of a second laser pulse based on a selected energy of the second laser pulse, a selected energy of the first laser pulse, and the feedback signal.