Analog vs Digital TV
Digital and analog TVs are two types of TVs available in the electronics market. Digital TVs are more modern compared to analog TVs. These devices are based on different designs and concepts. In this article, we are going to discuss what digital TV and analog TV are, the scientific concepts behind digital TV and analog TV, and finally the difference between digital TV and analog TV.
Analog TV
In order to understand the operation of analog TV, one must first understand the concept of analog signals. Most of the entities we encounter in our daily lives are analog entities. In physics, as well as electronics, analog is a term used to describe a signal or a function which can take any value over a given region. An analog signal is continuous. A sinusoidal voltage signal is a very good example for an analog signal. An analog signal has infinitely many values between any two given values. This is, however, limited by the capabilities and the resolution of the instruments used to measure these signals.
An analog TV is a television that uses analog signals to receive video and audio data. All televisions up to cathode ray televisions (CRTV) use analog signals. The earliest analog TVs used a disc with holes to transmit images. Today, analog TVs use frequency modulation to transmit sounds and amplitude modulation to transmit images. The video we see on a TV is, in fact, a series of images refreshed faster than the human eye can detect. Almost all of the analog TVs used in these days are based on the cathode ray tube. Analog televisions can either be wireless or can be operated using copper cables. Analog TVs use color systems such as PAT, NTSC and SECAM. These color systems are standards to define the signal shape corresponding to each color.
Digital TV
To understand the concept of digital TV, one must first understand the concept of digital signals. The term “digital” is derived from the word “digit” which means a specific number. A digital signal can take only discrete values. For example, the logic levels of 1 and 0 are digital values. A logic level between 1 and 0 or “true” and “false” doesn’t exist. If a digital signal is digitized with values very close to each other and with a large number of values, it can be said that the signal is a fine approximation for the corresponding analog signal.
A digital TV uses digital signals instead of analog signals. The individual pixel of a digital TV can be illuminated according to the incoming signal. TVs such as LCD, LED, and Plasma displays use digital signals. They are also designed to operate on analog signals due to backward compatibility of technology.
What is the difference between digital TV and analog TV?
• Digital TVs usually have better resolution, sharpness, contrast and clarity than corresponding analog TVs.
• Digital TV systems operate on digital signals, as well as analog signals, but analog TV systems only operate on analog signals.