Systems and methods for correcting power of an intraocular lens using refractive index writing

A system for improving vision of a subject, the system comprising:

• a pulsed laser system configured to apply laser pulses to an intraocular lens (IOL) in an eye of a subject, to change the refractive index of at least one selected area of the IOL of the lens by refractive index writing;
• a control system configured to receive data regarding a non-zero residual spherical error of the eye of the subject after implantation of the IOL and to estimate, after the implantation of the IOL, a diffractive power addition to the IOL required to either partially or fully correct the non-zero residual spherical error, wherein the control system comprises a sensor to measure the non-zero residual spherical error;
• and
• wherein the control system is coupled to the pulsed laser system and is configured to control the pulsed laser system to apply a plurality of laser pulses to the IOL, the laser pulses being configured to produce, by refractive index writing on the IOL, the estimated diffractive power addition to partially or fully correct the non-zero physical error, and wherein the application of the plurality of laser pulses to produce the estimated diffractive power addition is performed after the implantation of the IOL.