The Basics (Without the Boring Bits)

There are five key players that determine what a laser can do — and understanding them is like unlocking the skin treatment cheat code. If you’ve ever wondered why one laser lifts, another fades pigment, and a third smooths texture, this is where it all clicks into place.

You don’t have to be fluent in physics — just fluent enough to know what’s going on under the hood. These five concepts are what every good provider is balancing during your treatment. Here’s what they are, what they mean, and why they matter:

Wavelength

The laser’s vibe. Wavelength refers to the type of light the laser emits, measured in nanometers (nm). It determines how deep the energy travels into your skin and what it can treat.

• Short wavelengths (e.g., 532 nm) stay close to the surface — great for redness and pigment.
• Long wavelengths (e.g., 1064 nm) go deeper — perfect for hair, vessels, and collagen stimulation.

Curious where specific lasers land on the spectrum? (See the chart on the next page!)

Chromophore (The Target)

What the laser is aiming for — its target. A chromophore is the molecule or structure in your skin that absorbs the laser’s energy. Think of it as the bullseye.

• Melanin = pigment and hair
• Hemoglobin = vessels and redness
• Water = skin cells, collagen, texture

Each laser is matched to a chromophore. That’s what makes it effective — and safe.

Pulse Duration

How long the laser energy is delivered with each pulse. Also called pulse width, this controls how fast the laser “fires.”

• Too short = not enough energy absorbed.
• Too long = potential for heat to spread to nearby tissue.

The Goldilocks rule applies: just the right duration maximizes results and minimizes risks.

Energy (Fluence)

This is the laser’s strength. Measured in Joules/cm2, it tells us how much energy is delivered to your skin per pulse.

• Low fluence = subtle stimulation
• High fluence = more aggressive treatment

But more energy doesn’t always mean better results — it’s about the right dose, not the highest dose.

Spot Size

The size of the laser beam as it hits the skin. Spot size influences treatment speed, depth, and comfort.

• Smaller spots = targeted precision (ideal for tiny vessels or pigment spots)
• Larger spots = faster, deeper treatment (great for big areas like legs or backs)

A good provider adjusts spot size depending on the area and concern being treated.