How does a laser hair removal machine work? 
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Laser epilators are devices designed to remove unwanted hair using concentrated light energy. To understand how they work, let’s list the basic principles, technologies and biological interactions.
Operating principle
The laser hair removal device operates on the principle of selective photothermolysis. To do this, light of a certain wavelength is used, which affects melanin, the pigment in the hair follicles, without damaging the surrounding skin tissue. Light energy is absorbed by melanin and converted into heat, which damages the follicle and prevents further hair growth.
Types of lasers
Hair removal machines use different types of lasers, each of which has certain characteristics:
- Alexandrite Lasers (755 nm)
Known for their high absorption by melanin, alexandrite lasers are effective for treating fair to olive skin tones. They offer a good balance between speed and efficiency, making them suitable for covering large areas. - Diode Lasers (800-810 nm)
Diode lasers provide deeper skin penetration, making them versatile for a variety of skin types, including dark tones. They are often preferred for their ability to balance effectiveness and safety. - Nd:YAG lasers (1064 nm)
These lasers have a longer wavelength, which allows deeper penetration and less absorption of melanin. Nd:YAG lasers are especially effective for dark skin tones, but require more sessions to achieve desired results. - Ruby Lasers (694 nm)
Ruby lasers are one of the earliest types used for hair removal and are effective for fine and light hair. However, their use is limited due to the high absorption of melanin, which increases the risk of side effects in dark skin tones.
Mechanism of action
The laser emits a concentrated beam of light that is absorbed by the melanin in the hair shaft. The energy heats the hair, causing thermal damage to the hair follicle without affecting the surrounding skin. The heat generated denatures the proteins in the follicle, leading to the destruction of hair growth cells. This process, called photothermolysis, ensures that the follicle becomes inactive and cannot produce new hair.
The effectiveness of laser hair removal depends on several factors, including the contrast between skin and hair color, hair density and growth phase. Hair grows in three phases: anagen (growth phase), catagen (transition phase) and telogen (resting phase). Lasers are most effective in the anagen phase, when the hair follicle is actively producing hair and is rich in melanin. To target hair in different growth phases, several sessions are required, which are usually carried out at intervals of 4-6 weeks.
Safety and side effects
Modern devices are equipped with cooling mechanisms to protect the epidermis and minimize discomfort. Common cooling methods include contact cooling (cooled tip in contact with skin), cryogen spray, and air cooling systems. Possible side effects, although rare, may include erythema (redness), edema (swelling), and temporary pigment changes. Correctly assessing your skin type and adjusting the device settings helps reduce the risk of unpleasant side effects.
Recent advances have improved the effectiveness and safety of laser hair removal machines. Technologies such as SHR (Super Hair Removal) and IPL (Intense Pulsed Light) have emerged as alternatives or complements to traditional laser systems. SHR uses lower energy levels at higher repetition rates, which provides a more comfortable experience and reduces the risk of burns. IPL uses broad spectrum light and multiple wavelengths to target hair follicles, making it a versatile option for a variety of skin types and hair colors.
Care before and after the procedure
Before your treatment, you should avoid sun exposure, waxing, or plucking your hair for several weeks before your treatment. Shaving the treated area ensures that the laser targets the follicle and not the hair above the skin. Post-procedure care includes avoiding sun exposure, using soothing creams to reduce irritation, and following specific skin care recommendations provided by your doctor.
The popularity of laser hair removal has increased significantly due to its long-term cost-effectiveness and the growing demand for aesthetic treatments. Although initially expensive, the long-term reduction in hair growth results in cost savings compared to other hair removal methods. Socially, laser hair removal has helped change beauty standards and personal hygiene practices, becoming a routine procedure for many people who want to permanently get rid of hair.