Hair removal mode HR (695-, 755-nm wavelength)
With relatively high wavelength of pulsed light (700–800-nm red light) and stronger energy, it allows thermal energy to effectively penetrate into the skin to the inferior epidermal layer and make the follicles rich in melanin shrink or become atrophic, thus achieving the purpose of permanent hair removal. Therefore, as long as they are actual hairs (except fine hairs), regardless of the large-area hairs at the armpits, perineum (bikini line), hairline, forearm, or even calf, they are effectively removed by the hair removal mode. Compared with traditional laser hair removal (such as ruby or Alexander laser), pulsed light has a broader spectrum of light waves of different colors and better thermal permeability, whose results are less likely to be affected by race, skin color, or hair site. Moreover, the large probe of pulsed light can also expand the treatment scope and enable the affected site be homogeneously heated and is less prone to incur folliculitis or hair residue. Regarding its drawbacks, the treatment results are inferior to laser hair removal in the treatment of thin hairs; the number of treatment courses is relatively higher, and treatment results differ due to energy adjustment by the physician.
According to Dr. Chuang’s experience, pulsed light is most effective against thick hairs (such as armpit or leg hairs) but is not significant against thin or fine hairs (such as female fake beards or hand hairs). Generally, multiple courses are necessary to reach a clearance rate of over 90% (permanent hair removal), and the first 2-3 courses demonstrate the most distinct effects as they are able to remove approximately 30% of the hairs at each course, but the results gradually wane due to the growth period of hairs. Besides, the number of treatments for hairs at different sites also differs. Generally, 4–6 treatments are needed for armpit and perineal hair removal and 6–8 times are needed for forearm hairs; as calf hairs are abundant and widely distributed, over 8 treatments are usually required, which should be conducted at an interval of at least 1 month.