How do Fiber Optic Sights Work and Why Do You Need to Buy One?

Lately, you may have noticed that several gun companies and owners have begun installing something called a fiber optic sight on their guns. In fact, these manufacturers have started producing fiber optic sights separately and sell them as an additional accessory for firearms. Some experts also say that these devices are a must-have if you want to upgrade your firearms. They also claim that it is a worthy investment as you can aim better when shooting. Hence, most of us wonder how do fiber optic sights work and what are they exactly.

What are Fiber Optic Sights?

Fiber optics is more accurately called an optical fiber. In simple terms, it is basically a transparent and flexible fiber that has the ability to transmit light along its entire length. It is created by drawing glass and plastic through an aperture. The resulting fiber has a thickness that is almost equivalent to the width of human hair. Additionally, a typical fiber optic cable has an outer cladding and an inner core. Both of these have a very low refractive index which means that they do not bend any light.

However, the outer cladding is extremely reflective. That is why it can reflect light along the entire length of the cable, no matter how long it is. In fields like telecommunication, this plays a huge role as it can transmit more signal in comparison to a regular copper cable. Likewise, it is also more reliable than other forms of wire. What makes fiber optics more amazing is how well they can interact with light. This kind of properties are the reasons why fiber optic sights have become useful tools for firearms.

How Do Fiber Optic Sights Work?

When it comes to how fiber optic sights work, there is a bit of science that is involved, and we need to understand that before we go to the specifics.

The General Principle

As mentioned earlier, a fiber optic material is made up of a core layer material. Such material is filled with a fluorescing compound, which is responsible for reflecting light. It is also the one that primarily reacts to light. This is then surrounded by an extremely thin layer of sheathing which has a different index of refraction.

With that said, when an ultraviolet light enters the side of the fiber and then gets trapped inside, there is a possibility that it can no longer reflect back from the inside of the sheath. That is because there is a difference in the refractive indexes between the sheath and the core. The UV light then causes the material inside the core to fluoresce and emit light, which is now highly visible from the end of the tube. If the tube is long, then more of the light is captured as well as emitted from the tube.

Colored Fiber Optic Sights

You will find fiber optic sights in different colors such as green, yellow, orange or even red. In general, lights come in multiple colors, and their wavelength determines them. White light which is the one we typically perceive is a combination of all the colors throughout the spectrum. Hence, when the light gets sent through refractory objects, it gets split into various colors of the spectrum.

The green and yellow fiber optic sights tend to occupy more of the spectrum that is visible. That is why the green light’s wavelength ranges from 510 nm to 570 nm, wherein after that, the yellow light begins. On the other hand, the red light’s wavelength starts at 650 nm and goes higher. Here on, the light cannot be seen by the human eye as the wavelengths are too high.

As can be denoted above, humans can easily pick up light colors that have a wavelength anywhere between 400 nm and 700 nm. Therefore, the red light comes close to the limit of our vision. This is the same reason why people tend to find green lasers far more visible even in low light conditions.

What are Advantages of Using Fiber Optic Sights?

Incorporating fiber optics in handguns, shotguns, or any firearms, especially for beginners, has quite a few advantages. First, it helps in accurately aiming the target which in turn makes you enjoy the sports and encourages you to continue it. While they may not be an ideal choice during the night or in dark environments, fiber optic sights are incredibly superior during the daytime. In fact, people with aging eyes benefit the most from them as they find it incredibly easy to aim.

At night, you can use a handheld light along with the fiber optic sight as it will prove to be more powerful since it can absorb light quite well. Best of all, these add-ons will be significantly cheaper than using night sights. Nonetheless, if you choose to upgrade your firearms by using fiber optic sights, there are things that you need to consider.

How to Choose the Right Fiber Optic Sight?

When shopping for a fiber optic sight, ensure that you are selecting the right type that is specifically designed for the class and variant of your firearm. That is because even the slightest mismatch will have a negative effect on your shooting accuracy. You should also appropriately choose the fiber optic sight color for your firearm. As mentioned, wavelengths between the range 450 and 700 nm are ideal for the human eye. This range would include colors like green and yellow.

In addition, pay close attention to the circumference of the optic sight. Since only the rear is visible, the length is not as important. The bigger the circumference means that the sight will appear to be bigger as well. However, you do need to draw a line with how big the circumference should be since something that is too big might obstruct the target.


We hope that this article has provided you with the necessary information on how do fiber optic sights work and how they can help you during your hunting or target shooting adventures. Again, it goes without saying that fiber optic sights are a viable tool to carry with you as long as you purchase a model that will fit your firearms perfectly.