Light Adjustable Intraocular Lens Polymerization Control

The patent modifies the chemical parameters of the photoinitiator system by using a tandem photoinitiator combination (PI-1 and PI-2) with different absorption spectra and activation wavelengths. This allows the first photoinitiator to be completely deactivated at its activation wavelength while the second photoinitiator remains dormant and can be activated later if needed, ensuring complete deactivation without residual optical drift.

The patent introduces an intermediary substance (oxygen) that acts as a quenching agent for the photoinitiator radicals. Oxygen diffuses into the lens during the lock-in procedure and quenches any remaining active photoinitiator species, ensuring complete deactivation of photopolymerizable material and preventing subsequent optical power drift.

The patent segments the photoinitiator system into two distinct components: PI-1 (first photoinitiator) that is highly reactive and activated at a first wavelength for efficient polymerization adjustment, and PI-2 (second photoinitiator) that is less reactive and activated at a second wavelength for complete deactivation. This segmentation allows oxygen to quench PI-1 effectively during adjustment while PI-2 remains available for final lock-in without compromising overall efficiency.

The patent employs periodic action by performing two sequential lock-in procedures at different wavelengths. The first lock-in at the first wavelength activates PI-1 for initial stabilization, then a second lock-in at the second wavelength activates PI-2 for complete deactivation. This periodic approach ensures thorough quenching of photoinitiator activity while maintaining efficient polymerization adjustment during the first stage.