science

High-definition television

High-definition television is a science topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand High-definition television rather than just read about it. In short: High-definition television (HDTV; also known as high-definition or HD) describes a television or video system which provides a substantially higher image resolution than the previous generation of technologies. The term has been used since at least 1933; in more recent times, it refers to the generation following standard-definition television (SDTV).

Key takeaways

High-definition television belongs to science; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect High-definition television to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of High-definition television from memory before moving on to harder problems.

Reference excerpt

High-definition television (HDTV; also known as high-definition or HD) describes a television or video system which provides a substantially higher image resolution than the previous generation of technologies. The term has been used since at least 1933; in more recent times, it refers to the generation following standard-definition television (SDTV). It is the standard video format used in most broadcasts: terrestrial broadcast television, cable television, and satellite television.

Formats HDTV may be transmitted in various formats:

720p (1280 × 720p): 921,600 pixels 1080i (1920 × 1080i) interlaced scan: 1,036,800 pixels (≈1.04 Mpx). 1080p (1920 × 1080p) progressive scan: 2,073,600 pixels (≈2.07 Mpx). Some countries also use a non-standard CTA resolution, such as 1440 × 1080i: 777,600 pixels (≈0.78 Mpx) per field or 1,555,200 pixels (≈1.56 Mpx) per frame When transmitted at two megapixels per frame, HDTV provides about five times as many pixels as SD (standard-definition television). The increased resolution provides for a clearer, more detailed picture. In addition, progressive scan and higher frame rates result in a picture with less flicker and better rendering of fast motion. Modern HDTV began broadcasting in 1989 in Japan, under the MUSE/Hi-Vision analog system. HDTV was widely adopted worldwide in the late 2000s.

Standards

All modern high-definition broadcasts utilize digital television standards. The major digital television broadcast standards used for terrestrial, cable, satellite, and mobile devices are:

DVB, originating in Europe and also used in much of Asia, Africa, and Australia ATSC, used in much of North America DTMB, used in China and some neighboring countries ISDB, used in two incompatible variations in Japan and South America DMB, used by mobile devices in South Korea These standards use a variety of video codecs, some of which are also used for internet video.

History

… excerpt ends here. Continue reading the full article.

Worked examples

Example 1 — a first encounter with High-definition television

Start with the simplest possible case. Write down what High-definition television claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In science, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to High-definition television before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about High-definition television ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of High-definition television

In research: High-definition television appears in science research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses High-definition television in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: High-definition television is common in secondary-school and first-year university syllabi. It links to neighbouring topics ATSC, Consumer electronics, Digital television, so understanding it makes those chapters shorter.
In everyday life: Look for High-definition television outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

Ask Teacher Smith questions about this articleOpens your AI tutor with a question about “High-definition television” →

Affiliate

Preply — study more efficiently by working with a personal tutor. 50% off.

How to study High-definition television in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what High-definition television means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain High-definition television out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is High-definition television in simple terms?

Why does High-definition television matter?

Because it connects several science ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study High-definition television?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on High-definition television.