A popular topic in televisions nowadays is full HDTV (full high definition television). This is due to the full changeover of digital television (DTV) signal on June 12, 2009. With this transition complete, everyone has access to HDTV signal. However, not everyone has HD display because in order to get it, you must have an HDTV display television.
When talking about HDTV, the quality of the picture (or high resolution) is the main point. Anyone who chose to purchase or obtain an HD converter box still has an analogue picture on a CRT screen. The resolution of an NTSC-analogue TV described as 480i. The "i" in the description refers to the word "interlaced". The reason why is because the CRT tube in the analogue television only 240 horizontal lines available, but the television camera has 480 lines. Therefore, in order to present the look of a more vertical resolution, the television signal is interlaced. If you consider the aspect ratio of 4:3, using basic mathematics, you can see why the analogue TV resolution can be depicted as 640 x 480i.
HDTV and full HDTV are different from analogue TV due to the resolution of each. The standard HDTV has a resolution of 720i or 720p while a full HDTV has a resolution of 1080i or 1080p. The "p" instead of the "i" stands for progressive scanning. This means that the vertical scans are done simultaneously. Using a 16:9 aspect ratio, the standard HDTV is has 1520 x 720 pixels and the full HDTV has 1920 x 1080 pixels.
It seems that the full HDTV (1080p) would be the most desirable product for optimum resolution and viewing pleasure. However, on televisions smaller than 42 inches in size, the difference in the standard HDTV versus the full HDTV isn't visible. For this reason, full HDTV isn't available on smaller TVs. Only standard HDTV (720i or 720p) is available. Hence, a 42 inch screen television or larger is required if you wish to get the benefit of full HDTV.
Three choices of screen technologies are available for full HDTV. These are rear projection HDTV, full HD plasma TV and full HD LCD TV. Rear projection HDTVs are still available but this technology appears on the decline with many manufactures dropping out of the market. Therefore, one is left with full HD plasma TV and full HD LCD TV to choose between. Since a resolution of 1080p is assumed, other factors affecting image quality to consider are response time and refresh rate, contrast ratio and color reproduction.
Full HDTV plasma displays are bright, have a wide color range, and can be produced in fairly large sizes, up to 58 inches is commercially available. Because the display panel is only about 6 cm (2.5 inches) thick, the overall thickness is about 4 to 6 inches. Contrast ratios are as high as 50K to 100K are claimed but, in reality, the highest available in stores is 30K with response times at 0.001 milliseconds and refresh frequencies of 600 Hz. Fast response times make plasma TV's ideal for fast motion video (films or sports viewing). Plasma screens also are said to have better color reproduction than LCDs and to have a wider viewing angle.
However, the power requirements for a plasma TV can be as high as 500 watts. Also, plasma televisions are heavier than LCDs; however, plasma screens can be mounted on the wall.
Full HDTV LCD displays have the same resolution as plasma full HDTV displays, but the LCD displays have a slower response time (2 milliseconds). This could result in ghosting during fast moving images. The refresh frequency of an LCD display screen is 240 Hz, but the contrast ratio has been improved so that it's the same as the plasma screen (30K). Though there are some differences in response time and refresh frequencies, LCD TVs are less expensive than plasmas.
Other than resolution, the other features of the two full HDTV options are more up to interpretation and the desire of the consumer. Ultimately, full HDTV is the best choice, taking into consideration the extra cost. However, be careful to make sure that if you're looking into an entire home theatre that your full HDTV is compatible with the system.
When talking about HDTV, the quality of the picture (or high resolution) is the main point. Anyone who chose to purchase or obtain an HD converter box still has an analogue picture on a CRT screen. The resolution of an NTSC-analogue TV described as 480i. The "i" in the description refers to the word "interlaced". The reason why is because the CRT tube in the analogue television only 240 horizontal lines available, but the television camera has 480 lines. Therefore, in order to present the look of a more vertical resolution, the television signal is interlaced. If you consider the aspect ratio of 4:3, using basic mathematics, you can see why the analogue TV resolution can be depicted as 640 x 480i.
HDTV and full HDTV are different from analogue TV due to the resolution of each. The standard HDTV has a resolution of 720i or 720p while a full HDTV has a resolution of 1080i or 1080p. The "p" instead of the "i" stands for progressive scanning. This means that the vertical scans are done simultaneously. Using a 16:9 aspect ratio, the standard HDTV is has 1520 x 720 pixels and the full HDTV has 1920 x 1080 pixels.
It seems that the full HDTV (1080p) would be the most desirable product for optimum resolution and viewing pleasure. However, on televisions smaller than 42 inches in size, the difference in the standard HDTV versus the full HDTV isn't visible. For this reason, full HDTV isn't available on smaller TVs. Only standard HDTV (720i or 720p) is available. Hence, a 42 inch screen television or larger is required if you wish to get the benefit of full HDTV.
Three choices of screen technologies are available for full HDTV. These are rear projection HDTV, full HD plasma TV and full HD LCD TV. Rear projection HDTVs are still available but this technology appears on the decline with many manufactures dropping out of the market. Therefore, one is left with full HD plasma TV and full HD LCD TV to choose between. Since a resolution of 1080p is assumed, other factors affecting image quality to consider are response time and refresh rate, contrast ratio and color reproduction.
Full HDTV plasma displays are bright, have a wide color range, and can be produced in fairly large sizes, up to 58 inches is commercially available. Because the display panel is only about 6 cm (2.5 inches) thick, the overall thickness is about 4 to 6 inches. Contrast ratios are as high as 50K to 100K are claimed but, in reality, the highest available in stores is 30K with response times at 0.001 milliseconds and refresh frequencies of 600 Hz. Fast response times make plasma TV's ideal for fast motion video (films or sports viewing). Plasma screens also are said to have better color reproduction than LCDs and to have a wider viewing angle.
However, the power requirements for a plasma TV can be as high as 500 watts. Also, plasma televisions are heavier than LCDs; however, plasma screens can be mounted on the wall.
Full HDTV LCD displays have the same resolution as plasma full HDTV displays, but the LCD displays have a slower response time (2 milliseconds). This could result in ghosting during fast moving images. The refresh frequency of an LCD display screen is 240 Hz, but the contrast ratio has been improved so that it's the same as the plasma screen (30K). Though there are some differences in response time and refresh frequencies, LCD TVs are less expensive than plasmas.
Other than resolution, the other features of the two full HDTV options are more up to interpretation and the desire of the consumer. Ultimately, full HDTV is the best choice, taking into consideration the extra cost. However, be careful to make sure that if you're looking into an entire home theatre that your full HDTV is compatible with the system.
About the Author:
James Junior writes informative articles about Full HD TV including articles about Full HD Plasma television
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