How does Laser Tattoo Removal Work?

By now, everywhere you look you seem to see someone with tattoos. This trend really has taken the 21st Century by storm! As a result, tattoo artists are plentiful and their artwork is everywhere. Some of the work you see is magnificent, whereas others make you think that the ‘tattooist’ maybe is (most definitely is) in the wrong industry.

Bad tattoos are now everywhere. As a result, tattoo laser removal is becoming one of the biggest beauty treatments currently available. This is brilliant, because it means that the terrible tattoo you probably shouldn’t have got when you were 14 can be removed.

Maybe you are a laser technician wondering how tattoo removal works, or maybe you have a tattoo that you are absolutely sick to the death of seeing and just want gone. In this article I will run through everything you will ever need to know about tattoo removal.

How does tattoo removal work?

Before we understand this, we must first discuss how a tattoo actually stays in the skin.

The needle of the tattoo gun penetrates the skin and punches through the top layer of skin (called the epidermis). This deposits ink particles into the deep layer of the skin (known as the dermis). This triggers an inflammatory response (similar to what happens you fall over and cut yourself). A special type of cell called immune cells come to the area and actually ‘swallow’ the tattoo ink. At the same time, skin cells known as fibroblasts also soak up the tattoo ink. These fibroblasts and immune cells that now contain the tattoo ink stay suspended in the dermis and that lovely (or not so lovely in many cases) tattoo is visible forever.

This is where the magnificence of the tattoo removal machine comes in! These machines have been purposefully designed to target the ink and not cause damage to the rest of the body. ‘Well how does it do this?’ I hear you asking, well to understand this, we must firstly go through how the tattoo removal device works (Don’t worry its not as boring as it sounds).

Laser device

The laser device emits photons of light (which are little particles of light) which move in waves. Imagine I shone a torch at you, well the light that hits you from the torch has actually travelled in a wave-like pattern to reach you. Now, the distance between these waves make a wavelength and the wavelength of light determines the colour of the light and also what it does.

Light moves in different waves and different colours of light have different wavelengths

Now, these different wavelengths of light are absorbed by different particles in the skin (which we call chromophores). This is brilliant for us, because the tattoo particles also act as a chromophore which can absorb this laser light! If you look at figure 1. We can see how we can use this information to remove tattoos.

The tattoo removal device will often emit a 1064nm wavelength. This wavelength is absorbed by black and blue ink particles in the skin. Most tattoo removal devices will also come with a tip that allows you to emit a 532nm wavelength which is absorbed by red coloured ink particles, meaning that you can also remove red/orange/yellow tattoos (Green and purple tattoos are another story and can be a nightmare to remove depending on the device you have).

Figure 1. Coloured ink particles absorption of light

So, what happens when these particles of ink in the skin absorb the laser?

Simply, they are then destroyed. Now, how this happens is up for debate. It is likely that when the ink particle absorbs the light, this generates heat which causes the ink particle to fragment (i.e. expand and crack) which causes pressure waves within the skin which further destroys the pigment into smaller pieces. A second theory states that the laser device causes the oxidation of the ink particles, which basically means that when the ink particle absorbs the laser light, the chemical structure of the ink particle is changed meaning it is broken down.

When the light hits the ink, the ink is broken into smaller particle via oxidation or acoustic waves

Now that the ink particles have been broken up into smaller pieces, the lymphatic system in the body can remove these smaller particles and you can simply excrete them from the body (i.e. when you go to the toilet).

What is the Lymphatic system?

The lymphatic system is a system that runs in parallel with your circulatory system (i.e. veins and arteries) that removes waste.

The Lymphatic system

How does this not cause damage to the rest of the human body?

To answer this, we must first go back in time to the 1980’s…… in 1983, two researchers uncovered what is called the ‘Theory of Selective Photothermolysis’. This revolutionised the way we can remove tattoos! This theory states that the pulse of the laser (the energy that it emits per shot) must be less than or equal to the thermal relaxation time of the target (i.e. the time taken for the particle to lose 50% of its heat) so that only the target is destroyed and not the surrounding tissue.

Now I know what you’re thinking, this sounds complicated. In simple terms, if we fire the laser at an ink particle in the skin, it must lose half of its heat before it can be hit again with the laser so no damage is done to the surrounding skin. Ink particles lose heat very quickly, so they must be hit extremely quickly with light to effectively be destroyed and removed. A very simplistic example of this would be when we cook bacon, we wouldn't let it cool down at any point during cooking.

When we cook, we keep the bacon warm at all times. You would not put the bacon in the pan for a second and then remove it until it gets cold. This is similar to the Theory of Selective Photothermolysis

This brilliant research led to the invention of the Q-switch laser removal device, which changed the way we can remove tattoos forever. These devices release energy with pulse widths in the nanosecond range (and even picosecond range [which is known as a pico machine]) which match the thermal relaxation time of the ink particle and destroy it which minimises damage to the surrounding skin. This is why the Q-switch device is currently the best device on the market and the gold standard for tattoo removal. In the correct hands, with a laser technician who is safe and qualified, they are an excellent strategy for the removal of tattoos.

Which supplier should I use?

I offer several machines on my website ranging from E-light devices to tattoo removal devices. Prior to opening this business, I worked in medical research facilities throughout the United Kingdom for my PhD. Following this, I developed these devices myself to ensure maximum efficiency and safety! Unlike some suppliers, I will not rip you off with astronomical pricing. Remember, I offer a free consultation to answer any questions you may have.

Thank you for reading!

Written by Dr Lockhead

0113 418 0464