Laser hair removal is an effective method of depilation or
removing unwanted body hair by using devices that send out electromagnetic
radiation called lasers.
The laser, which is actually an acronym for Light
Amplification by Simulated Emission of Radiation, uses highly concentrated,
invisible light to destroy the undesirable hairs by using a process called selective
photothermolysis.
Selective photothermolysis simply means that the laser beam is
able to choose specific target hairs and destroy them without damaging the
surrounding skin. The laser is able to do this by emitting light beams at
wavelengths that target the melanin in the hair follicles.
Melanin is the pigment that gives skin and hair their color.
The dark melanin in the hair follicle absorbs light from the laser beam which
is then transformed into the heat that destroys the hair follicle.
As a result of this process of selective photothermolysis
that targets the dark melanin, the best candidates for laser hair removal are
those with dark colored black or brown hair and light or fair skin. Consequently,
persons who may not have good results from laser hair removal are those with
white hair, grey hair or fine blond hair.
Laser hair removal is also most successful when the hair
follicle is in the anagen phase. This is the stage in which the hair follicle
is actively growing and thus its destruction results in hair loss. Since hair
grows in cycles, and around 85% of hair follicles are in the anagen stage at
any one time while the rest are in the other resting and shedding stages, laser
hair removal is not a one-time procedure.
A client may therefore need to have several sessions to destroy the hair follicles which were not in their active phase
during their last laser hair removal treatment session. On average, five
treatments are required for each area before all the active hair follicles are
destroyed and permanent hair reduction achieved.
These treatment sessions are usually spaced out depending on
the hair cycle length for the body area being treated to ensure that the hairs
which were resting, have entered the anagen or growing phase. For instance,
laser hair removal treatment sessions for facial hair can be done monthly,
those for the bikini area bimonthly, and those for the legs every six weeks.
These durations are not standard for all clients since they also depend on the
gender, hair density and degree of hair removal required.
The Difference Between True Lasers and "IPL" Lasers
There are several differences
between a true laser (Light Amplification by Simulated Emission of Radiation) and an IPL (Intense pulse light) laser.
The first of these is that a true laser
emits monochromatic light with a single wavelength while an IPL emits polychromatic
light with multiple wavelengths which can range from 515 nm to 1200 nm. As a result of this
difference, a single IPL device can be used on many clients and on a wider
range of skin types and hair colors than would be possible with a single laser
device. This is because a laser’s specific wavelength targets specific
conditions since the the absorption of light by the skin and hair depends on
the wavelength of the light.
In addition, true laser devices treat skin conditions at specific depths in the skin while an
IPL device can be used to treat multiple conditions at different levels within
the skin since the different wavelengths of light from an IPL which are chosen
by using different filters, can penetrate the skin to different depths. A
result of this difference is that IPL treatments are usually less expensive
than laser treatments since one IPL machine can treat multiple conditions.
The third difference is
that a true laser is collimated while an IPL is non-collimated. This means that
the true laser light does not disperse a lot as it moves from its origin to its
target, while the IPL light quickly spreads out making it less effective than
the powerfully focused true laser for some purposes such as hair reduction.
A fourth difference is that
a true laser is coherent while an IPL is not coherent. This means that light
from a true laser beam produces a synchronized phase of light waves that do not
cancel themselves out while an IPL does thus making it less effective than the
reinforcing laser for some cosmetic procedures.
The fifth difference
between true lasers and IPL machines is that the risk of skin discoloration
from hyperpigmentation or hypopigmentation is less with IPL devices, especially
when they are used for hair removal, since they cause less damage to the surrounding
skin than lasers though true lasers give more superior results.
In addition, due to the use
of pulsed light in IPL, the risk of the skin burning is less than that of using
lasers. Conversely, the “gentler” and less intensive treatments from IPL
machines result in the client needing more repeat visits to achieve a certain
goal than if they had received intensive laser treatment in the first
place.
