Understanding Basic TV Terminology

 

A very basic what-is-what guide on some terms related to Televisions today

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Trying to buy a new TV can be an absolute nightmare if you aren’t familiar with any of the terminology, it could mean you end up purchasing a sub-standard television or simply something you don’t want or need.

Here we’ve provided some of the most basic terminology you’ll need to know when trying to find a new television.

What Exactly Is A HD TV?

A HD TV (High Definition TV) is simply a television that can show stuff in high definition, as opposed to standard definition. As you can see from the picture below, high definition is far superior to standard definition.

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Bare in mind that you will need to watch HD television channels or HD films to get the benefit of high definition, as if you watch standard definition channels on a HD TV, it will still be standard definition. So, it all depends on the input.

The main reason HDTVs output can look better than standard definition TVs is because of the screen resolution.

What Does Screen Resolution Mean?

Screen resolution signifies the amount of pixels that a television has. A television is made of up of thousands of tiny individual lights which are called pixels, the more pixels, the higher the amount of detail.

In general, HDTVs resolutions are mentioned as 720p, 1080i, 1080p. So what are these ?

The number (720 or 1080) refers to the display resolution and the letter (i/p) refers to the HDTV source resolution.

1080i and 1080p means a screen resolution of 1920×1080 implies that the display has 1920 horizontal pixels and 1080 vertical pixels. So, the total number of pixels in the TV is = 1920 x 1080 = 2,073,600 pixels.

1080p_tv_resolution_meaning

720p resolution is a common term used to generalize lower HD resolutions of  and 1024x768, 1280x720 or 1366x768. Todays widescreen HDTVs of 720p resolution have a resolution 1366x768 pixels.

1080p, sometimes referred to in marketing materials as Full HD.

Difference between 1080p and 1080i

The letter “p” means progressive scan and “I” means interlaced scan.

1080p_tv_resolution_meaning_2

In interlaced scan a single frame can be considered to be made up of 2 parts of 540 lines each (1080 divided by 2). First all the odd lines (1,3,5 ..) are displayed first. After 1/60th of a second, the even numbered lines (2,4,6…) are shown. So, as a result the complete frame is got every 1/30th of a second. The frame rate in 1080i resolution is 30 frames per second (in case of NTSC based TVs). However in PAL TVs the frame rate is 25 frames per second.

In progressive scan the entire frame is displayed at once. So, the frame rate is increased from 30 frames per second to 60 frames per second in NTSC TVs and to 50 frames per second in PAL TVs.

So, obviously the 1080p resolution is better than 1080i. However, most of the HD sources broadcast the content in 1080i resolution only. So, in general, the difference cannot be found easily.

Find more about the differences here.

How Are TV Sizes Measured?

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TV sizes are measured from opposite corners, for instance from the top left hand corner to the bottom right hand corner and vice versa. So if you measured a 60 inch TV horizontally across, it would actually measure a few inches lower than sixty inches.

What is the Difference Between An LCD, Plasma And LED Screen?

These are the three most common screen types and they are very similar apart from a few positives and negatives.

LCD (liquid crystal display) screens are the cheapest televisions to buy on average, but the picture quality isn’t as good as LED or plasma screens. LCD screens also have low power consumption levels. LCD televisions produce a black and colored image by selectively filtering a white light. The light is typically provided by a series of cold cathode fluorescent lamps (CCFLs) at the back of the screen. More about LCDs here.

LED TVs: Actually LED TVs are also a variant of LCD TVs. It is just for marketing purpose that Samsung has first started off branding them as LEDs. LEDs are actually not part of commercial TV segments at all. Then what are these LED TVs ? These are LED backlit LCD televisions. They are also kind of LCD TVs except that the backlighting technology varies in LCD and LEDs. More about LED TV here.

Plasma screens deliver the highest picture quality of the three; the prices are generally higher than LCD screens and similar to LED screens. However since they have glass screens, they suffer from screen glare plus they have high power consumption levels. More about Plasmas here.

What is Aspect Ratio?

Aspect ratio describes the proportional ratio between the width and the height of the display.

It can be expressed as width by height (16:9 for widescreens – 1920 x 1080 resolution is a wide screen resolution).

This guest post was written by Matt from 60InchTVs.org, where he provides reviews and buying information for 60 inch TVs. Check out his article on the best 60 inch TVs for the money.

The article is intended for a basic understanding of various terms related to present day TVs. Stay tuned to The Netizens updates for a detailed HDTV buying guide to be published soon. 

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