From a lighting technology point of view, there are 2 main categories of layer cages: those with external feeders and those with internal feeders. Therefore, there are 2 types of lighting systems depending on the type of cage used.
In both cases, the most important area to be lit is the feeder, which, in order to be seen by the birds in the cage, requires an amount of light that achieves at least 30-40 lux over the feeder.
For cages with external feeders, the lighting comes exclusively from rows of lamps placed in the corridors between the cages and above the cages, with special lenses that narrow the light beam to focus on the feeders; for cages with internal feeders, the system consists of rows of lamps that run inside the cages, requiring one line for every row and for every level of cages.
Given the low amount of light required for these systems, the most recommended products are low voltage lamps, studied according to the type of system you have.