Electromagnetic sunscreen model: implementation and comparison between several methods: step-film model, differential method, Mie scattering, and scattering by a set of parallel cylinders.

Sunscreens protect from UV radiation, a carcinogen also responsible for sunburns and age-associated dryness. In order to anticipate the transmission of light through UV protection containing scattering particles, we implement electromagnetic models, using numerical methods for solving Maxwell's equations. After having our models validated, we compare several calculation methods: differential method, scattering by a set of parallel cylinders, or Mie scattering. The field of application and benefits of each method are studied and examples using the appropriate method are described.