Understanding the Science Behind Fluorescent Lighting

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Have you ever wondered how fluorescent lighting works? You may have noticed that it differs from other types of lighting…but how? Here’s all the science you need to know behind fluorescent lighting!

What’s Fluorescent Lighting?

What is fluorescence? Essentially, the term describes how certain chemicals absorb radiation before then giving off light. As you’ll explore later, this type of lighting has many benefits, and this has led to many different uses in society. These days, you’ll find fluorescent tubes in hospitals, schools, and many other public locations.


Despite having small differences, the terms ‘neon’ and ‘fluorescent’ are nearly interchangeable these days. While businesses use fluorescent lighting inside buildings, they may also use these neon signs in Adelaide outside buildings to attract attention.

History of Fluorescent Lighting

Before starting the science lesson, let’s look at some history. In 1901, Peter Cooper Hewitt, an electrical engineer in the United States, progressed on the earlier works of Heinrich Giessler and Julius Plucker. Using a glass tube, Hewitt used an electrical current to interact with small amounts of mercury. Soon enough, the tube lit up, and this became the foundation of fluorescent lighting.

In the modern world, this technology has undergone a few changes. Yet, the underlying system all stems from this initial experiment from Hewitt.

How Does Fluorescent Lighting Work?

In simple terms, we turn on the switch at the wall and this passes an electrical current through mercury. As this mercury converts into gas, it collides with various atoms and electrons. As these electrons get excited, the energy inside the tube increases. Then, the electrons relax and there’s a reduction in energy levels. After this process, light photons are released. However, the process isn’t over because the light can only become visible after the photons hit phosphor (normally the coating on the tube).

To summarise, the important components are the electrical current, mercury, and the phosphor coating on the tube. Also, you might see three different types of fluorescent lighting:

     Hot cathode

     Cold cathode


Although they bring minor differences, they all contain the same interactions between electrons and the phosphor coating to generate light.

Fluorescent Lighting vs Incandescent Bulbs

How does fluorescent lighting differ from incandescent bulbs, and why are experts recommending the former over the latter? One problem with incandescent bulbs is the wasted energy as the light forms through a heated filament. While incandescent bulbs produce lots of heat, fluorescent tubes don’t get as hot. Why? Because the pressure is low as the current produces UV light.

While fluorescent tubes do generate some heat, it’s nothing compared to incandescent bulbs, and it quickly disperses thanks to the larger surface area on fluorescent lighting.

Secondly, another reason why experts are recommending fluorescent lighting is that all excess UV light is utilised with this form. Sadly, UV light generated by incandescent bulbs is wasted.

Benefits of Fluorescent Lighting

     Energy efficiency. Compared to a traditional light bulb, fluorescent lighting saves an average of 30% in energy usage.

     Long light life. While incandescent light bulbs offer up to 1,500 hours, fluorescent lighting lasts an average of 10,000 hours. However, some have claimed that they have extended beyond 50,000 hours.

     Lower costs. With energy efficiency and longer life, it makes sense for both homeowners and businesses to consider fluorescent lighting.

Drawbacks of Fluorescent Lighting

     Higher initial cost. Despite the long-term savings, fluorescent lighting is more expensive at the start. Therefore, you’ll need to remember the long-term savings when paying up to three times as much for the solution.

     Mercury content. Also, the EPA in the United States claims that fluorescent lighting contains around 4mg of mercury. Though a small quantity, it presents disposal challenges for older/damaged lights.