Laser Device Selection: Which Wavelength for Pigment, Wrinkles and Texture, and Why?

"Laser" is not a single device but a family of different wavelengths and technologies. The device is chosen according to the target (pigment, hair, vessel, wrinkle, texture renewal); skin type (phototype) is also a critical factor. A wrong target–device match is both ineffective and risky. This guide explains the physician's laser/device selection logic.

First: what does a laser target?

Laser/light energy heats a specific "chromophore" (target molecule):

• Melanin → pigment/spot and hair treatments
• Haemoglobin → vessels/redness
• Water → texture renewal, wrinkles (ablative/fractional)

Device selection begins by choosing the wavelength best suited to the targeted chromophore.

General match by target

Pigment and spots

Systems that target pigment (e.g. Q-switched / picosecond technologies) are used. Here phototype is very important: in darker skin, epidermal melanin also absorbs energy, so the risk increases and the wavelength and setting are chosen accordingly.

Hair (laser hair removal)

Targets melanin in the hair root. Shorter wavelengths in light–medium skin and longer wavelengths (e.g. Nd:YAG) in darker skin are generally considered safer because they target the epidermis less.

Vessels and redness

Systems that target haemoglobin are used; the superficial–deep vessel distinction affects wavelength selection.

Wrinkles and texture renewal

Ablative (e.g. CO2/Erbium) or fractional systems that target water provide tissue renewal and collagen stimulation; recovery time and risk increase with aggressiveness.

Phototype: the factor that drives selection

The Fitzpatrick I–VI classification describes the skin's melanin content. In darker skin (IV–VI) the risk of pigment complications (darkening/PIH, lightening) is higher; therefore:

• Longer wavelengths and more conservative settings may be preferred,
• A test shot (spot test) is performed,
• The procedure is postponed in tanned skin.

Decision framework (general)

The most common mistake: expecting "one laser does everything"

No single device can treat every target optimally. A good clinic selects the technology suited to the target and the setting suited to the phototype; the "if all you have is a hammer, everything looks like a nail" approach increases the risk of poor results and complications.

Our Clinic's Approach