Evaluation of the Tolerance (Main Objective) and Performance of Cyto-selective Difluoroethane-based Cryotherapy in the Treatment of Brown Spots (Solar and Senile Lentigines, Post-inflammatory Hyperpigmentation) on the Face

The goal of this clinical trial is to compare the 3 different prototype of cyto-selective cryotherapy devices (name of the devices : CRYONOVE) use in brown spots on the face of subject from different ethnicities. The main questions it aims to answer are: * the tolerance of 3 prototypes of cyto-selective cryotherapy treatments * the performance of 3 prototypes of cyto-selective cryotherapy treatments Participants will be treated for each spots with a definied prototype during 6 treatment visits. Researchers will compare the tolerance and performance of the 3 prototypes.