1. Photonic skin rejuvenation and whitening principle: intense pulsed light with different wavelengths produces selective effects on tissues, thus producing different characteristics of photo-biochemical and photo-pyrolysis reactions. Photon rejuvenation stimulates collagen fibers and elastic fibers through long-wave light, which causes chemical changes in molecular structure of collagen fibers and elastic fibers in dermis, rearranges them, thickens collagen tissue, enhances skin elasticity, improves skin quality and whitens skin. 2. Whitening principle of black-faced dolls: Apply carbon powder to the face, and according to the principle that carbon powder can absorb dirt and keratin under the skin, use laser scanning, and use the high thermal conductivity of carbon powder medium to break the dirt on the epidermis and melanin in the dermis to achieve the ideal whitening effect. In principle, photon rejuvenation and black-faced doll whitening are both laser beauty treatments, but in fact, many formal and professional plastic surgery hospitals have already eliminated photon rejuvenation and replaced it with more advanced color light rejuvenation, black-faced doll and ruby laser whitening. Why? Because photon skin rejuvenation treatment usually depends on the personal feelings and experience of doctors, and the treatment equipment such as light skin rejuvenation and black-faced dolls are very intelligent, and doctors are trained to work, so the safety and effect are greatly improved. The whitening effect of black-faced dolls is very good. Taking the black-faced doll in Guang Mei Plastic Surgery Hospital as an example, the following effects can be achieved: 1. Whitening skin and improving dullness II. Brighten luster, even skin tone 3. Firming skin and reducing pores. Refreshing skin and balancing oil 5. Smooth skin and remove superficial spots. Crystal tender, synchronous rejuvenation because the treatment of black-faced dolls is very safe. Therefore, black-faced dolls are not only more effective but also safer than photon rejuvenation and whitening. Here, experts from Guang Mei Plastic Surgery Hospital remind consumers that black-faced dolls belong to medical beauty projects, and it is best not to go to beauty salons with only life beauty qualifications, so as to avoid adverse effects on health and even disfigurement.