A method of designing a laser writing system for modifying a plurality of ophthalmic devices, the method comprising: (a) determining at least one material characteristic of the ophthalmic devices, determined over a range of laser writing system parameters; (b) determining at least one design characteristic of the ophthalmic device; and (c) using at least the determined material and design characteristics, configuring at least one system parameter of the laser writing system to optimize throughput of the laser writing system, the laser writing system comprising: (i) a laser configured to generate a laser beam, (ii) a splitter configured to split the laser beam into a plurality of outputs, and (iii) a plurality of writing heads, each writing head configured to direct at least one of the outputs to an ophthalmic device to write one or more localized refractive index modifications into the ophthalmic device; wherein the at least one design characteristic includes a maximum phase shift designed for the ophthalmic device to be written in the ophthalmic device with the laser writing system without causing optical damage in the ophthalmic devices; wherein the at least one material characteristic includes at least a first damage threshold for an induced single layer optical phase shift of the ophthalmic device at a first laser repetition rate, and a second damage threshold for an induced single layer optical phase shift of the ophthalmic device at a second laser repetition rate; and wherein optimizing throughput of the laser writing system comprises determining an optimal number of writing layers for modifying the ophthalmic devices in combination with an optimal number of writing heads of the laser writing system for optimizing throughput of the laser writing system and obtaining the maximum phase shift designed for the ophthalmic device without causing optical damage in the ophthalmic devices. (a) determining at least one material characteristic of the ophthalmic devices, determined over a range of laser writing system parameters; (b) determining at least one design characteristic of the ophthalmic device; and (c) using at least the determined material and design characteristics, configuring at least one system parameter of the laser writing system to optimize throughput of the laser writing system, the laser writing system comprising: (i) a laser configured to generate a laser beam, (ii) a splitter configured to split the laser beam into a plurality of outputs, and (iii) a plurality of writing heads, each writing head configured to direct at least one of the outputs to an ophthalmic device to write one or more localized refractive index modifications into the ophthalmic device; (i) a laser configured to generate a laser beam, (ii) a splitter configured to split the laser beam into a plurality of outputs, and (iii) a plurality of writing heads, each writing head configured to direct at least one of the outputs to an ophthalmic device to write one or more localized refractive index modifications into the ophthalmic device; wherein the at least one design characteristic includes a maximum phase shift designed for the ophthalmic device to be written in the ophthalmic device with the laser writing system without causing optical damage in the ophthalmic devices; wherein the at least one material characteristic includes at least a first damage threshold for an induced single layer optical phase shift of the ophthalmic device at a first laser repetition rate, and a second damage threshold for an induced single layer optical phase shift of the ophthalmic device at a second laser repetition rate; and wherein optimizing throughput of the laser writing system comprises determining an optimal number of writing layers for modifying the ophthalmic devices in combination with an optimal number of writing heads of the laser writing system for optimizing throughput of the laser writing system and obtaining the maximum phase shift designed for the ophthalmic device without causing optical damage in the ophthalmic devices.