Hair Growth Cycle：Growth phase, Catagen phase, Resting phase
Laser hair removal is only effective for hair in the growth phase and has little effect on the catagen and telogen phases. Therefore, laser hair removal requires 3 to 5 times for the effect to be effective. Many people will never need to remove hair again in their lifetime. The fact is that after laser hair removal, it can only stabilize the number of hair regeneration in the treatment area at a lower level than before for a long period of time after the treatment. Some hair removal areas may have a small amount of fine villi, which is not obvious and Small number.
Principle: Selective Photothermolysis Theory
This theory refers to the fact that objects produce special thermal energy properties when illuminated by visible light. Its main characteristic is that only light of a given color can be absorbed by an object, while light of other colors is reflected or transmitted.
Wavelength
Semiconductor laser: Wavelength: 808nm/810nm double-pulse laser can slowly increase the temperature of the irradiated skin, is gentle to the skin, and improves hair removal efficiency without causing pain and other adverse reactions.
Alexandrite laser: Wavelength: 755nm, high energy. If the ice application time is not long enough, adverse symptoms such as erythema and blisters often occur.
Intense pulsed light: Wavelength: 480nm~1200nm. The short wavelength is absorbed by the melanin in the epidermis and the hair shaft, dispersing part of the energy on the surface of the skin, and the remaining energy acts on the melanin in the hair follicles.
YAG laser: Wavelength: 1064nm. Single wavelength. The wavelength is relatively penetrating and can concentrate on deep hair follicles. It is beneficial to darker skin, hairline and lips. Lips are also suitable because the hair is thin and light in color, with less melanin in the hair follicles and poor light absorption. The hairline is too thick and dense and has more melanin.
Three-wavelength lasers are relatively comprehensive to hair removal equipment. Absorption, penetration, and coverage are important factors when using laser treatment to remove hair. This laser provides enough wavelengths for hair removal. The principle of using three-wavelength lasers is "the more, the better." Combining the three wavelengths is expected to produce better results in less time than a single wavelength laser. Triple diode laser technology provides clinicians with an integrated solution when using lasers. This new laser offers the advantages of three different wavelengths in one device. The handpiece of this laser device reaches different depths within the hair follicle. Using three different wavelengths together may yield beneficial results regarding these parameters. Clinician comfort and convenience are not compromised when using triple-layer diode lasers for hair removal. Therefore, three-wavelength diode laser can be a comprehensive option for hair removal. This laser may be especially beneficial for people with darker skin. It has the deepest penetrating ability and works on deeply embedded areas such as the scalp, armpits, and genitals. Efficient cooling within the device makes the hair removal process almost painless. Now a new long pulsed 940 nm diode laser used for hair removal in Asian skin types.
Post time: Mar-08-2024