Wavelengths have the property of being absorbed only by specific substances, and in cosmetology, the effects of heat and shock waves generated by the absorption of wavelengths are used to improve skin problems. For example, if you want to improve blemishes, the wavelength absorbed by the melanin pigment, if you want to improve the reddish face, the wavelength absorbed by the hemoglobin of the blood, etc., the required wavelength is selected and the treatment is performed.