Introduction
Understanding laser wavelengths is fundamental to successful aesthetic practice. Each wavelength targets specific chromophores in the skin, making wavelength selection crucial for optimal treatment outcomes.
Here's a comprehensive list of the most popular laser wavelengths used in aesthetic medicine, along with explanations of their primary uses and mechanisms:
1. 532 nm – Green Laser (KTP Laser)
Uses:
- Vascular lesions (e.g., spider veins, telangiectasia)
- Red acne scars
- Rosacea
- Pigmented lesions
How it works:
Targets oxyhemoglobin and melanin, making it ideal for treating red or brown discolorations.
Skin types:
Best for lighter skin tones (Fitzpatrick I–III).
2. 585–595 nm – Pulsed Dye Laser (PDL)
Uses:
- Port-wine stains
- Vascular birthmarks
- Rosacea
- Broken capillaries
- Red acne scars
- Hemangiomas
How it works:
Absorbed by oxyhemoglobin, causing selective photothermolysis of blood vessels.
Skin types:
Typically Fitzpatrick I–III; caution with darker skin.
3. 755 nm – Alexandrite Laser
Uses:
- Hair removal
- Pigmented lesions (e.g., age spots, sun spots)
- Tattoos (especially green ink)
How it works:
Targets melanin, which absorbs the energy and destroys unwanted pigment or hair follicles.
Skin types:
Best for lighter skin types (I–III); higher risk of pigment changes in darker skin.
4. 810 nm – Diode Laser
Uses:
- Hair removal
How it works:
Penetrates deeper than 755 nm, targeting the melanin in hair follicles for permanent reduction.
Skin types:
Safe and effective across a broader range of skin types (I–V), depending on the system used.
5. 940–980 nm – Diode Laser (Vascular Applications)
Uses:
- Deeper vascular lesions
- Leg veins
- Venous lakes
How it works:
Targets hemoglobin and water, helping coagulate deeper vessels.
6. 1064 nm – Nd:YAG Laser
Uses:
- Hair removal
- Vascular lesions (including deeper blue veins)
- Non-ablative skin rejuvenation
- Onychomycosis (nail fungus)
How it works:
Penetrates deeply and is less absorbed by melanin, making it safe for darker skin tones.
Skin types:
Safe for all skin types, including VI.
7. 1320–1440 nm – Nd:YAG or Fractional Lasers
Uses:
- Non-ablative skin tightening
- Collagen stimulation
- Acne treatment
How it works:
Targets water in the dermis, promoting collagen remodeling without damaging the surface.
8. 1540–1550 nm – Er:Glass / Non-ablative Fractional Lasers
Uses:
- Skin resurfacing
- Acne scars
- Fine lines
- Texture improvement
How it works:
Heats the dermis via water absorption, promoting collagen remodeling with minimal downtime.
Skin types:
Safe for most skin types with proper settings.
9. 2940 nm – Er:YAG Laser
Uses:
- Ablative skin resurfacing (wrinkles, scars, pigmentation)
- Laser peels
How it works:
High water absorption leads to precise ablation of the skin's surface with controlled thermal injury.
Skin types:
Best for lighter skin tones; safer than CO2 for darker skin.
10. 10,600 nm – CO2 Laser
Uses:
- Deep skin resurfacing
- Wrinkles
- Scars
- Warts
- Skin tightening
How it works:
Strongly absorbed by water, causing tissue vaporization and coagulation for dramatic results.
Skin types:
Best for lighter skin (I–III); requires caution with darker skin due to hyperpigmentation risk.
Electromagnetic Spectrum for Aesthetic Lasers
To create a comprehensive understanding of laser wavelengths, it's important to understand where these specific wavelengths fall within the electromagnetic spectrum:
Wavelength Ranges:
- Ultraviolet (UV): 10 – 400 nm
- Visible Light: 400 – 700 nm
- Near-Infrared: 700 – 1400 nm
- Mid-Infrared: 1400 – 3000 nm
- Far-Infrared: 3000 – 1,000,000 nm
Key Takeaways for Practitioners
Understanding these wavelengths and their specific applications is crucial for:
- Selecting appropriate treatments for different skin types and conditions
- Setting proper expectations with patients
- Ensuring safety and optimal outcomes
- Building a comprehensive aesthetic laser practice
Conclusion
Mastering laser wavelengths is fundamental to successful aesthetic practice. Each wavelength serves specific purposes, and understanding their mechanisms of action, ideal applications, and skin type considerations will help you deliver optimal patient outcomes while maintaining the highest safety standards.
