Systems and methods for improving vision of a subject implanted with an intraocular lens (IOL). In some embodiments, a method includes determining at least one photic phenomenon experienced by the subject after implantation of the IOL; and applying a plurality of laser pulses to the IOL, the laser pulses being configured to produce, by refractive index writing on the IOL, a phase shift in the IOL to compensate for the photic phenomenon.