Liquid-crystal display televisions (LCD TV)
Liquid-crystal display televisions (LCD TV) are television sets that use LCD display technology to produce images. LCD televisions are thinner and lighter than cathode ray tube (CRTs) of similar display size, and are available in much larger sizes. When manufacturing costs fell, this combination of features made LCDs practical for television receivers.
In 2007, LCD televisions surpassed sales of CRT-based televisions worldwide for the first time,[citation needed] and their sales figures relative to other technologies are accelerating. LCD TVs are quickly displacing the only major competitors in the large-screen market, the plasma display panel and rear-projection television. LCDs are, by far, the most widely produced and sold television display type.
LCDs also have a variety of disadvantages. Other technologies address these weaknesses, including organic light-emitting diodes (OLED), FED and SED, but as of 2011 none of these have entered widespread production.
High-definition
It was the slow standardization of high definition television that first produced a market for new television technologies. In particular, the wider 16:9 aspect ratio of the new material was difficult to build using CRTs; ideally a CRT should be perfectly circular in order to best contain its internal vacuum, and as the aspect ratio becomes more rectangular it becomes more difficult to make the tubes. At the same time, the much higher resolutions these new formats offered were lost at smaller screen sizes, so CRTs faced the twin problems of becoming larger and more rectangular at the same time. LCDs of the era were still not able to cope with fast-moving images, especially at higher resolutions, and from the mid-1990s the plasma display was the only real offering in the high resolution space.
Through the halting introduction of HDTV in the mid-1990s into the early 2000s, plasma displays were the primary high-definition display technology. However, their high cost, both manufacturing and on the street, meant that older technologies like CRTs maintained a footprint in spite of their disadvantages. LCD, however, was widely considered to be unable to scale into the same space, and it was widely believed that the move to high-definition would push it from the market entirely.
This situation changed rapidly. Contrary to early optimism, plasma displays never saw the massive economies of scale that were expected, and remained expensive. Meanwhile, LCD technologies like Overdrive started to address their ability to work at television speeds. Initially produced at smaller sizes, fitting into the low-end space that plasmas could not fill, LCDs started to experience the economies of scale that plasmas failed to achieve. By 2004, 32" models were widely available, 42" sets were becoming common, and much larger prototypes were being demonstrated.
The type of TV
Name
|
Size
|
Ratio
|
Abbreviation
|
Common name.
|
Low Definition Television.
|
480 × 320.
|
3: 2.
|
LDTV (320p).
|
High-definition televisions. (Now deprecated).
|
Standard Definition Television.
|
640 × 480.
|
4: 3.
|
SDTV (480p).
|
Standard definition TV. (Used in some countries).
|
Enhanced Definition Television.
|
640 × 480.
|
4: 3.
|
EDTV (480p).
|
Standard resolution calls scenery. (Now deprecated).
|
High Definition Television.
|
1920 × 1080.
|
16: 9.
|
HDTV (1080p).
|
Call scenery in high definition. (Used in some countries).
|
Quad Full High Definition Television.
|
3840 × 2160.
|
16: 9.
|
QHDTV (2160p).
|
Call scenery very high resolution. (Television format is going to happen in the future).
|
Super Hi-Vision Television.
|
7680 × 4320.
|
16: 9.
|
SHVTV (4320p).
|
Call up the scenery. (Television format is going to happen in the future).
|
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