In 1995, ruby laser (694nm) was used to remove excess hair. In 1996, emerald (755nm) and neodymium doped yttrium aluminum garnet laser (1064nm) were also used to remove excess hair;
In 1998, semiconductor laser (810nm) was developed and applied to hair removal, and finally became the wavelength gold standard of hair removal project.
694nm and 755nm equipment, design concept – “burn down” the hair follicle, and use high energy to heat the temperature of the hair follicle and hair root to 60-70 ℃, so as to destroy the hair follicle. This kind of laser equipment is characterized in that the hair removal process is easy to cause burns, blisters and strong pain in patients;
Second generation laser hair removal equipment
The traditional semiconductor hair removal laser 810nm is slow and painful, although the risk of scald is reduced due to the poor absorption of melanin in the basal cell layer;
The design concept of the third generation freezing point hair removal laser – low energy density, high average power, painless and rapid hair removal;
Scientists have found that when the temperature of the hair follicle rises to about 45 ℃ and remains for a period of time, the hair follicle and the stem cells growing around the hair follicle will be destroyed and apoptotic, so as to remove excess hair.