In this blog post, we’ll examine the functions, transmission and reception methods, and types of TVs, as well as their evolution into digital and smart TVs, and explore the direction in which TVs are likely to evolve in the future.
What Is a TV, and What Does It Do?
“The idiot box.” This is a term that has become a staple whenever people talk about TV. It’s closely tied to TV viewing habits. It’s a metaphor for the habit of lying in a corner of the room in pajamas, mindlessly flipping through channels with the remote control—a phrase that has often been used to raise awareness, especially among children who spend a lot of time in front of the TV. However, times have changed significantly. The children who used to sit in front of the TV have now shifted their attention away from a TV that merely delivers one-way video content to internet-based computers and smartphones that can interact with users. Online games, search engines, messaging apps, and video streaming services are all built on these interactive networks. So, has the TV—once stigmatized as the “idiot box”—now ceded its place to computers and smart devices, reduced to nothing more than an electronic appliance decorating the living room? Not at all. Just as the times have changed, the TV has also continued to evolve. In this article, we’ll examine the TV’s functions, transmission and reception systems, different types, and the evolution leading up to today’s smart TVs.
Dictionaries define TV as “a method of electrical communication that transmits optical images of objects via radio waves to reproduce them on a receiving device, or the device that receives such images.” The English word “television” is a combination of the Greek word “tele” (far) and the Latin word “vision” (to see). It was given this name because, unlike radio, it was a device capable of transmitting images over long distances via radio waves. In other words, the most basic function of television is to transmit video and sound, allowing viewers to see scenes from distant locations in real time.
Television went beyond being a mere device for transmitting images to exerting significant social influence when it became widespread in ordinary households due to mass production and technological advancements. After television established itself as a mass medium, it came to fulfill three main functions: news, entertainment, and education. By delivering news from local, national, and global sources through video, television became a news medium that conveyed information more vividly than text-based newspapers.
Furthermore, with the broadcast of sports events, variety shows, and dramas, watching TV became one of the most popular ways for people to spend their leisure time. In the past, when television penetration rates were low in South Korea, neighbors would gather at homes with televisions to watch Olympic events or popular dramas together. This serves as a good example of television’s entertainment function. Even today, dramas and variety shows make up a significant portion of terrestrial broadcasts, various pay-TV services, and internet-based broadcasting services; given that viewer interest and demand have a major influence on programming schedules, television’s entertainment function continues to play a vital role.
Another important function of television is education. Through television, people can indirectly experience diverse societies and cultures they would not otherwise encounter firsthand, and they can naturally learn the values and lifestyles shared by members of society. Children, in particular, undergo socialization through this process. Furthermore, television serves as an educational medium by conveying specialized knowledge and diverse information through documentaries, educational programs, and cultural programs.
How Are TV Broadcasts Delivered?
Given that TV broadcasts serve such diverse functions, what process do they go through to reach viewers? First, companies that produce broadcast content and TV programs create the shows. These companies are called PPs (Program Providers). The produced programs are delivered to households through regional cable TV operators or cable broadcasters, which are referred to as SOs (System Operators). PPs are responsible for producing content, while SOs are responsible for delivering it to subscribers. Today, various broadcast delivery methods operate in parallel, including not only cable TV but also IPTV and internet-based streaming services.
Meanwhile, there are broadcasts that can be received using only an antenna without going through an SO; these are terrestrial broadcasts. In South Korea, KBS, MBC, SBS, and EBS are representative terrestrial broadcasters. These stations transmit signals via transmission towers, and households receive them using antennas. When driving on a highway, you can see large transmission towers installed on mountain peaks or other high points; these facilities are responsible for transmitting broadcast signals. Today, with the increase in high-rise buildings and changes in the broadcasting environment, the number of households watching terrestrial broadcasts using only an antenna has decreased compared to the past. Instead, the number of households using cable TV, IPTV, satellite TV, and internet-based TV services has increased significantly. Satellite TV has the advantage of allowing viewers to reliably watch a variety of channels using a satellite dish, even in areas where it is difficult to receive broadcast signals.
What electronic devices can a TV be connected to?
In addition to watching broadcasts, a TV is used as a display device that outputs various video content by connecting to external input devices. In the past, people often connected VCRs to watch movies, and later, DVD players replaced them. Today, DVDs are rarely used; instead, it is common to connect set-top boxes, game consoles, Blu-ray players, laptops, PCs, and streaming devices via digital interfaces such as HDMI. Furthermore, with the widespread adoption of smart TVs, users can now directly access internet video services and various applications without the need for separate external devices.
What types of TVs are there?
TVs have evolved into various forms—such as CRT, LCD, PDP, and OLED—in line with technological advancements.
CRT (Cathode-Ray Tube) TVs are commonly referred to as “tube TVs.” They work by having electrons emitted from one or more electron guns strike a fluorescent material at the back of the screen, causing it to emit light. The electrons fired from the electron guns are guided to the desired positions using electric and magnetic fields to form the image on the screen. Because this structure requires sufficient space for the electrons to travel, the product inevitably becomes thicker. Furthermore, as the screen size increases, so do the size and weight of the TV, and power consumption tends to be high. Due to these structural limitations, production of CRT TVs has largely ceased since the widespread adoption of flat-panel displays.
LCD (Liquid Crystal Display) TVs use liquid crystals to control the amount of light that passes through. The arrangement of liquid crystal molecules between two glass plates is controlled by voltage to either allow or block light entering from behind. Simply put, the principle is similar to adjusting the angle of blinds to change the amount of light entering a room. Early LCD TVs used cold cathode fluorescent lamp (CCFL) backlights, but today, most models employ LED backlighting, which uses LEDs as the light source. Products commonly referred to as “LED TVs” are actually LCD panels equipped with LED backlights. LCDs are easy to manufacture with a thin and lightweight design, have relatively low power consumption, and provide a clear picture even in bright environments.
PDP (Plasma Display Panel) works by generating plasma within numerous small cells to cause a phosphor material to emit light. Since each pixel emits its own light, a backlight is unnecessary, allowing for wide viewing angles, natural color reproduction, and an excellent contrast ratio. While PDPs delivered outstanding picture quality, particularly on large screens, they had the drawbacks of high power consumption, significant heat generation, and heavy weight. Subsequently, as LCD technology advanced rapidly and manufacturing costs decreased, PDPs gradually disappeared from the market and are no longer produced.
Today, OLED (Organic Light-Emitting Diode) occupies a prominent position in the premium TV market. Since each pixel in an OLED emits its own light, a backlight is unnecessary, allowing for the reproduction of true black and a very high contrast ratio. It also offers an ultra-thin profile and excellent viewing angles, establishing itself as the leading display technology for high-end TVs.
Recently, alongside OLED, new display technologies such as Mini LED and Micro LED have also been advancing.
In the past, LCDs had limitations in producing large screens, so PDPs dominated the large-screen TV market; however, as companies including Samsung Electronics and LG Electronics advanced large-screen LCD panel technology, LCD TVs became capable of producing large screens as well. Furthermore, with continuous improvements in response speed and picture quality, the competitiveness of LCD TVs has significantly increased. Currently, LCD and OLED models form the core of the TV market, with LCD leveraging its price competitiveness and OLED its superior picture quality as their respective strengths.
What has changed with digital TV?
South Korea ceased terrestrial analog broadcasting as of December 31, 2012, and fully transitioned to digital broadcasting. Since then, terrestrial TV has only been available via digital broadcast. So, what advantages does digital TV offer compared to traditional analog TV?
The biggest advantage is superior picture and sound quality. Since digital broadcasting transmits video and audio using digital signals composed of 0s and 1s, it is less susceptible to external noise than analog broadcasting, which uses continuous electrical signals. As a result, the picture is sharper and the sound quality remains more stable. Furthermore, advances in digital compression technology have made it possible to efficiently broadcast more channels within the same frequency band. Initially, the MPEG-2 standard was primarily used, but today, more efficient video compression technologies such as MPEG-4 AVC (H.264) and HEVC (H.265) are widely utilized.
Another feature of digital TV is its ability to offer a variety of additional functions. While analog TV was limited to simply watching broadcasts as transmitted by the station, the digital broadcasting environment now supports various features such as electronic program guides (EPGs), scheduled viewing, closed captioning, and multi-channel broadcasting. Furthermore, with the advent of internet-connected smart TVs, users can now access a wide range of functions that go beyond the traditional concept of broadcasting, including video on demand (VOD), streaming services, and app execution.
How have smart TVs evolved?
Advances in digital technology ultimately led to the emergence of smart TVs. Smart TVs have evolved from devices used solely for watching broadcasts into comprehensive media platforms connected to the internet that allow users to access a wide range of services. Users can install and utilize various applications, accessing features such as online video services, music streaming, internet searches, video calls, gaming, and screen mirroring—all from a single device.
While early smart TVs emphasized social networking services and basic web browsing, the core functionality of today’s smart TVs has shifted to accessing various online video services such as YouTube, Netflix, Disney+, Apple TV+, Coupang Play, Wavve, and TVING. Furthermore, integration with smartphones has advanced significantly, making it commonplace to mirror a mobile device’s screen onto the TV or control the TV using voice-activated artificial intelligence.
In this way, the TV has evolved from a simple screen for displaying video into a device that provides various digital services based on the internet and networks. Today’s smart TVs perform some of the functions of computers and smartphones while leveraging the advantage of a large screen to establish themselves as the central media device in the home.
How will TVs evolve in the future?
So far, we have examined the TV’s roles in news, entertainment, and education; its broadcasting transmission and reception systems; and its evolution into digital and smart TVs. Along with advances in digital technology, the TV has transformed from a simple broadcast receiver into a smart device that provides diverse content and services. It is now evolving beyond a medium for passively watching broadcasts into a comprehensive media platform that utilizes the internet and artificial intelligence.
Going forward, the TV is expected to continue evolving, focusing on higher resolution, superior picture quality, AI-based personalized services, and connectivity with various smart home devices. Furthermore, its role as a central hub for connecting and controlling various digital devices within the home is likely to become even more important.
Once known as the “idiot box” for changing people’s lifestyles, TV has now established itself as a core digital device that encompasses daily life, culture, information, and entertainment, going far beyond a simple broadcasting device. It will be interesting to see how TV, along with new technologies, will continue to transform our lifestyles in the future.
