IMAGE No. 16/17 The ray focused by the Ratok®derm equipment on the vitiligo patch penetrates down to the skin basal layer, where it restores, or reactivates, the melanocytes responsible for melanin production. This process looks like filling a glass: the filling material (melanin) covers the bottom at first, then gradually fills the whole glass (the vitiligo patch). Layer after layer, from the bottom to the top (blue arrows), the Ratok®derm light ray promotes repigmentation of melanin-free cells. Thus, patch "closure" does not result from shrinking, but rather from surfacing of the last, final melanin-rich layer.