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Factors of Laser Hair Removal

It would be surprising if you haven’t considered trying laser hair removal by now. Almost everyone has some form of unwanted body hair. Many hail it as a magical hair removal method. The technician merely waves his magic laser wand over the unwanted hair and it is gone forever. This is wishful thinking. There is a great deal of science involved in laser hair removal, and many factors can affect the quality of the treatment.

Beam Strength

It is obvious that the strength of the laser beam affects the quality of the laser hair removal session. Just as it is more effective to extinguish a flame with the water pressure of a fire hose than with a garden hose, the “light pressure” of a laser can make the difference between excellent results and no results at all. The doctor must control the beam strength carefully, such as through the time of exposure.


Many different laser wavelengths have been tried for laser hair removal. The wavelength is a measure of the distance between adjacent waves of the laser light. Lasers are characterized by the material used to create the laser light, such as alexandrite, argon, and ruby & Yag. Each material generates laser light of a specific wavelength, and some wavelengths of laser light are more effective against hair than others.

Beam Width

The laser beam width is the diameter of the circle that the laser beam makes on the skin. The ideal beam width is estimated to be four times as wide as the distance that the beam must travel into the skin. For example, if the hair roots were 0.05 inches beneath the skin, the ideal beam width would be about 0.20 inches wide.


Most laser hair removal is performed by the technician holding the laser over a specific area and turning the laser on for a specific time period. This time period is known as the pulse width. If the pulse width is too short, the hair might not be destroyed. If it is too long, the surrounding skin may be damaged. The technician may vary the pulse width until he finds one that works for each specific patient.

Cooling The Skin During Treatment

One of the newer developments is the cooling of the skin during laser hair removal treatment. Skin cooling allows the technician to use a “hotter” laser for longer periods of time without damaging the skin. Several methods of skin cooling are performed before, during, or even after the treatment.

Skin and Hair Color

The microwave oven targets the moisture in food, vibrating it up until it heats up and cooks the food. Similarly, laser hair removal targets color. Better results are obtained when there is a great contrast between the skin color and the hair color. Specifically, black hair in the very pale skin is the ideal laser hair removal scenario. On the other hand, blonde or white hair in that same very pale skin would be more difficult to remove, because there is little hair color for the laser to target. The darker the patient’s skin is, the more of the laser gets absorbed into the skin, and the fewer lasers light reaches the unwanted hair.

A Science And An Art

Many scientific variables control the effectiveness of laser hair removal. However, the technician must use professional judgment to vary these things so that each patient receives the best possible hair removal treatment.

science of laser hair removal