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the hair root must selectively absorb the light energy and
convert it into heat.
This selectivity is achieved when the optical energy that is
released into the tissue is mainly absorbed by the melanin
pigment in the hair. The high-energy light is converted into
thermal energy (heat), which ultimately deactivates hair
growth. Therefore, the more melanin present in the hair (i.e.
the darker the hair), the more light can be absorbed and
the more effectively the light can work for the hair removal.
What effect does the hair growth cycle have on light-
based hair removal?
Every hair on our body goes through the three phases of the
hair growth cycle: anagen, catagen and telogen. Only hairs
that are in the anagen phase, or growth phase, respond to
treatment with IPL. Although the duration of a complete hair
growth cycle differs from person to person and depends on
the area of the body the hair is growing on, the cycle generally
lasts 18 to 24 months.
Please note that at least one complete hair growth cycle is
required in order to achieve permanent hair removal using
the Beurer IPL PureSkin Pro.
Anagen –
growth phase
Catagen –
transitional phase
Telogen –
resting phase
18 – 24
months
Anagen
Telogen
Catagen
Long-term hair reduction
Skin types are depicted on the Fitzpatrick scale below. Darker
skin contains more melanin, which competes with melanin
in the targeted hair for energy absorption. When more light
energy is absorbed into the skin, there is a greater risk of
adverse effects and epidermis damage. This device is only
recommended for use on skin types I through IV.
