The mechanism of laser hair removal is based on the selective targeting of the melanin pigment present in the hair and hair follicles. The wide absorption curves without any peaks make it easier for the all the laser beam to hit melanin with accuracy. The absorption curve spans the entire ultraviolet, visible, and infrared light ranges.

Why Long Pulsed Lasers are preferred

• Lasers with longer wavelength falling in range such as ruby laser at 694nm, alexandrite laser at 755 nm, and Nd: YAG laser at 1064 nm can destroy the dermal papilla, which lies at 2-5 mm subsurface, because they offer deeper penetration. The ruby laser penetrates 1-2 mm, while the Nd: YAG laser penetrates 4-6 mm.

• Longer wavelength lasers are relatively safer and offer more protection for melanin-laden epidermis.

Types of Long Pulsed Lasers

Four wavelengths are used to remove hair.

• Long pulse (normal mode) ruby laser at 694 nm

• Long pulse alexandrite laser at 755 nm

• Long pulse diode laser at 800-810 nm

• Long pulse Nd: YAG laser at 1064 nm
  
  

Advantages of Long Pulsed Lasers

• Long pulse lasers are ideal for their availability of surface cooling

• Epidermal protection (from surface cooling and longer pulse duration) is another advantage of long pulse laser in laser hair removal procedure.

• Hair loss is the main result which is required by laser hair removal treatment and studies spanning long times stamped that long pulse laser hair removal systems can achieve a significant delay in hair regrowth.

• It is also assumed Nd:Yag 1064 nm system is the best for darkly pigmented patients

Disadvantages

The only know disadvantage is that it is not as effective for lightly pigmented hairs as for dark pigmented hair and for light pigmented hairs short pulse laser hair removal procedure should be adopted.

Conclusion

The long pulsed laser is ideal for dark colored hairs as compared to the short pulsed lasers which are more suitable for the light colored hairs. Their effectivity is further enhanced by the effective cooling systems which further minimize the laser hair removal side effects.