... times/week after improvement.Treat acne, while repair damaged skin How it worksLED cold light, also known as cold laser,is a ... . During the treatment, photosensitive collagen could be used, and it could lead into hypoderma fast and efficiently, absorbed by cell ... promote metabolism, make skin secrete collagen and fibrous tissue; meanwhile, it increases white blood cell's phagocytosis, and then comes to ...