What Is Fiber Optics?

Key takeaways

Fiber optic technology uses cables to transmit data in pulses at the speed of light using thin optical glass fibers. 

• Working in fiber optics could yield salaries ranging from $58,000, the average for tower technicians [1], to $136,000, the average for fiber optic design engineers [2].

• Fiber optics has uses across industries, including health care, automotive, networking, and telecommunications.

• You can start a career in fiber optics in several ways, including by earning IT certifications like a Certified Fiber Optic Technician (CFOT) beginner credential from the Fiber Optic Association. 

Explore how fiber optics works, the industries that rely on it, and careers in fiber optics. To expand your career options, consider enrolling in a program like the IBM Data Engineer Professional Certificate. This beginner-level 16-course series helps you learn practical skills, including how to design databases, analyze data, and work with tools like Apache Spark and Hadoop. After completing the program, you'll earn a shareable certificate that can boost your resume and LinkedIn profile.

How does fiber optics work?

Fiber optics, sometimes called optical fibers, transmit data by converting electronic signals into near-infrared light. Once converted to light pulses, the data travels along optical glass fibers until it reaches a decoder and returns to its original signal. It is possible to send light signals through optical fiber materials because of their differences in the incidence of refraction, a property within them that allows light beams to refract down the strand continuously. Fiber optic cables have three components:

• The core: Made from either glass or plastic, this part of the cable transmits the light. 

• The cladding: This component is made of the same material as the core but with a slightly lower refraction index, creating continual reflection along the cable.

• The outer coating: This coating is made of plastic and sometimes reinforced with metal. It holds the optical fibers together and protects them from environmental factors. 

Single-mode vs. multimode fiber

In fiber optics, cable types differ by their core composition and core and cladding diameter, measured in microns. A micron is one millionth the size of a meter. Fiber optics use two different “modes” of cables to send light, depending on the use case and the distance needed. 

The two modes are:

• Single-mode: This type of fiber has a smaller core, forcing light to travel in a singular ray. The light can travel longer distances than multimode. 

• Multimode: This fiber’s larger core enables light to travel in many different rays, which limits its speed and distance compared to single-mode. 

Multimode fiber further breaks down into step-index and graded-index fiber. Step index is only used in plastic optical fibers (POF) and is outdated compared to graded and single-mode, although it is still used in some consumer products. Graded index fiber has more bandwidth than step index fiber and comprises networks, LANs, and security systems. Single-mode fiber, meanwhile, has even more bandwidth than graded index, making it useful in applications that require high speeds and long-distance cable runs. 

Fiber optics and photonics

An increase in the use of fiber optics has led to more research in photonics, the study of creating, controlling, and detecting particles of light (photons). Photonics is what allows for the transmission and reception of light signals through fiber optic cables. Electrical-to-optical transducers use light-emitting diodes (LEDs) or laser diodes to change the original signal into light. In contrast, optical-to-electrical transducers convert the signal back to its source data. New research in photonics can increase the speed and reliability of fiber optic systems. 

Is fiber optic better than WiFi? 

WiFi is a better choice when you need both connectivity and mobility. However, fiber optic offers increased speed and reliability, with stronger security and ultra-low latency. Those characteristics make it a better choice if you need smooth, responsive, fast service. 

Who uses fiber optics?

Various industries now use fiber optics to transmit data, including health care, automotive, computer networking, and telecommunications. Let’s take a closer look at how each industry benefits from fiber optics. 

Fiber optics in health care

Not only does fiber optics meet the health care industry’s high demand for networking, it has aided medical discoveries and the use of technology in this field. Devices like endoscopes, arthroscopes, bronchoscopes, X-rays, CAT scans, and MRIs all use fiber optics to provide doctors with better tools to diagnose patients and view specific body parts during surgery. 

Fiber optics in the automotive industry

With innovations in safety, anti-collision sensors, and navigation systems, the automotive industry is taking advantage of fiber optics’ high bandwidth. Between autonomous driving, infotainment systems, and the now-required networking of a car’s electronic systems, cameras, radar, brakes, airbags, and so on, which uses POF to make all this possible. 

Fiber optics in networking

Fiber optics in networking allows for increased speeds, creating high-speed internet. The ability of fiber optic cables to transport data over longer distances than coaxial cables makes them advantageous for internet service providers (ISPs). This enables the larger bandwidth and the ability to stream, play video games, and connect the Internet of Things (IoT) all on the same network with little slowdown. 

Fiber optics in telecommunications

Like networking advantages, fiber optics in telecommunications allows for speed and a reliable signal to connect people across long distances. In addition, fiber optic cables have much less signal interference than copper coaxial cables. These advantages facilitated innovation and growth in the industry. 

Pros and cons of fiber optics

While fiber optics provides fast and reliable data transmission, the technology has some limitations. Let’s examine the pros and cons of creating a fiber optic network or switching to fiber optics.

When deciding whether fiber optics is right for you or your business, consider the options above. However, note that fiber optic technology is rapidly taking over because of its speed and reliability. 

How to start a career in fiber optics

You can start a career in fiber optics by becoming FOA certified through certification training from a school approved by the Fiber Optic Association. Some employers offer on-the-job training, and you can also become certified after two years on the job. 

Becoming FOA certified 

The Certified Fiber Optic Technician (CFOT) is the beginner certification for fiber optic technicians; this requires demonstrating knowledge and skills in the field. To obtain the certification, you will have to pass an FOA examination. You can advance your career with an FOA specialist certification for those already certified. Certifications vary based on your skills but range from data center and residential cabling to fiber optic splicing and fiber optic network design. 

Careers in fiber optics (with salaries)

The job outlook for telecommunication technicians projects 23,200 openings every year from 2024 to 2034 [3]. Below is a list of occupations in fiber optics:

• Fiber technician

• Tower technician

• Fiber optic splicer

• Telecommunications engineer

• Fiber optics design engineer

Look at each career, its requirements, and its average annual salary. 

*All salary information represents total median pay, which includes base salary plus bonuses, commission, and other forms of additional compensation.

Fiber technician 

Average annual salary in US (Glassdoor): $60,000 [4]

Fiber technicians work to repair, install, and upgrade telecommunications systems. They may work to find weaknesses in a system, run testing, and determine the upgrades needed to ensure the system is functioning properly. You typically only need a high school diploma, GED, or sometimes an associate degree or certification for this role. 

Tower technician 

Average annual salary in US (Glassdoor): $58,000 [1]

Tower technicians install, repair, and perform preventive maintenance on cell phone towers. They also work with coaxial cables, antennas, and fiber optics. You will climb cell phone towers to do your work, requiring training from a trade school for repair and safe tower climbing. 

Fiber optic splicer 

Average annual salary in US (Glassdoor): $70,000 [5]

Fiber optic splicers use a fusion splicer to splice fiber optic cables together for concatenation and terminals. Becoming this type of technician requires a high school diploma or GED. You can also get a specialist certification called a CFOS/S from the FOA, with a prerequisite of the CFOT certification. 

Telecommunications engineer 

Average annual salary in US (Glassdoor): $117,000 [6]

Telecommunications engineers frequently specialize in a specific area, such as voice, data, or fiber, and work to lead the replacement, upgrade, and repair of telecommunications systems. This role often requires earning a bachelor’s degree in information technology with telecommunications experience. 

Fiber optics design engineer

Average annual salary in US (Glassdoor): $136,000 [2]

Fiber optics design engineers work with clients to analyze their current system, then make a plan and work with many different departments to install a fiber optics system. To qualify for this role, you must have knowledge of network topology, fiber splicing, routing, and leadership skills. Employers typically look for candidates with a bachelor’s degree in engineering or telecommunications. 

Read more: 10 Entry-Level IT Jobs and What You Need to Get Started

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