755nm · Melanin Absorption · CityLink Mall
The alexandrite's 755nm wavelength is absorbed by melanin more strongly than any other laser in routine aesthetic use. That is precisely why it works so well, and precisely why it demands more care in darker skin — the laser cannot distinguish pigment in a hair follicle from pigment in the epidermis above it.
Every laser in aesthetic medicine is defined by three numbers, and the alexandrite is no exception: what wavelength it emits, what absorbs that wavelength, and how long each pulse lasts. The alexandrite emits at 755nm, at the far red end of the visible spectrum. Its target chromophore is melanin. Its pulse durations sit in the millisecond range. Those three facts predict everything the device does well and everything it does badly.
Selective photothermolysis is the governing principle. If a wavelength is absorbed far more strongly by the intended target than by surrounding tissue, and if the pulse is delivered over a period shorter than the time that target takes to shed its heat — its thermal relaxation time — then the target is destroyed while its neighbours are spared. For hair, the target is melanin within the hair shaft and matrix, and the heat must conduct outward far enough to damage the follicular stem cell region. Millisecond pulses are matched to that requirement.
Melanin absorption falls as wavelength increases. At 755nm it is high; at 1064nm, the Nd:YAG wavelength, it is substantially lower. This is the whole trade-off. High absorption means efficient energy transfer into pigmented targets — which is why the alexandrite is so effective against fine and light-brown hair that longer wavelengths struggle to heat, and why it clears superficial epidermal pigment briskly. The 755nm beam also penetrates less deeply than 1064nm, keeping its effect nearer the surface.
The difficulty is that melanin in the epidermis is the same chromophore as melanin in the follicle. The laser has no way to prefer one over the other. In lightly pigmented skin the contrast between a dark hair and a pale epidermis is large, and the treatment is straightforward. As constitutive pigmentation increases, that contrast narrows, the epidermis absorbs a greater share of the delivered energy, and the margin between an effective treatment and an epidermal burn becomes correspondingly thin.
What Changes
The alexandrite is an excellent device used in the right skin and a risky one used carelessly in the wrong skin. Singapore's patient population spans the full Fitzpatrick range, frequently within one family, so the question is never whether the alexandrite is a good laser — it is whether it is the right laser for this particular patient, this site and this season.
A laser that sees melanin cannot tell whose melanin it is. In Asian skin that single fact governs every setting.
The Decision
Atelier Aesthetics uses the Lutronic Clarity II for laser hair removal, a platform that delivers both 755nm alexandrite and 1064nm Nd:YAG. The reason a dual-wavelength device matters is not versatility for its own sake — it is that the correct wavelength is a per-patient and often per-site decision. Fine hair on a fair forearm and coarse hair in a deeply pigmented axilla are not the same problem, and being able to select the wavelength rather than defend the one the clinic happens to own is a clinical advantage.
For pigment, the alexandrite's role is narrower than its reputation suggests. It clears discrete, well-defined epidermal lesions — solar lentigines and similar superficial pigment — efficiently, because that pigment sits where 755nm energy is concentrated. It is a poor choice for melasma, where aggressive melanin-targeted heating reliably provokes rebound and worsening; that condition belongs to low-fluence laser toning and a considered medical plan. Deeper dermal pigment is better addressed by picosecond devices that shatter rather than cook it.
The honest summary is that 755nm is a specific tool with a specific window, not a general-purpose laser. In this practice it is chosen when the target is shallow and melanin-rich and the epidermis can tolerate the energy required to reach it. Where those conditions are not met, a different wavelength or a different pulse regime is used instead — and the reasoning is explained at consultation rather than reduced to a brand name.
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Atelier Aesthetics · Owned by AYA
1 Raffles Link, #B1-28, CityLink Mall, Singapore 039393 · +65 8023 7170
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