In order for a Television to be classified as an HDTV, or HDTV-ready, the television must be able to display at least 1280x720 pixels. Some of those "budget" Plasma televisions priced at $1,000 or less, that are "selling like hotcakes" only display 852x480 or 1024x768 pixels. These sets are referred to as EDTVs (Extended or Enhanced Definition televisions) or ED-Plasmas.
EDTVs typically have a native pixel resolution of 852x480 or 1024x768. 852x480 represents 852 pixels across (left to right) and 480 pixels down (top to bottom) on the screen surface. The 480 pixels down also represent the number of lines (pixel rows) from the top to the bottom of the screen. By the same token 1024x768 represents 1024 pixels across (left to right) and 768 pixels down (top to bottom) on the screen surface. The 768 pixels down also represent the number of lines (pixel rows) from the top to the bottom of the screen.
The images on these sets look great, especially for DVDs and standard digital cable, but it is not true HDTV. Plasmas that are capable of displaying HDTV signals accurately have a native pixel resolution of at least 1280x720 or higher.
These resolutions (852x480 and 1024x768) are higher than standard television, but not HDTV resolution. 1024x768 comes close, in that it meets the vertical pixel row requirements for a high definition image, but does not meet the horizontal pixel row requirements for a full high definition image.
As a result, some manufacturers label their 1024x768 Plasma televisions as EDTVs or ED-Plasmas, while others label them as Plasma HDTVs. This is where looking a advertised specifications are important. If you are looking for a true HD-capable Plasma Television, check for a native pixel resolution of either 1280x720, 1366x768, or 1920x1080. This will provide a more accurate display of high definition source material.
Since Plasma televisions have a finite number of pixels (referred to as a fixed-pixel display), signal inputs that have higher resolutions must be scaled to fit the pixel field count of the particular Plasma display. For example, a typical HDTV input format of 1080i needs a native display of 1920x1080 pixels for a one-to-one point display of the HDTV image.
However, if your Plasma television only has a pixel field of 1024x768, the original HDTV signal must be scaled to fit the 1024x768 pixel count on the Plasma screen surface. So, even if your Plasma television is advertised as an HDTV, if it only has a 1024x768 pixel pixel screen, HDTV signal inputs will still have to be scaled down to fit the Plasma Television's pixel field.
By the same token, if you have an EDTV with 852x480 resolution, any HDTV signals will have to be scaled down to fit an 852x480 pixel field.
In both of the above examples, the resolution of the image actually viewed on the screen does not always correspond to the resolution of the original input signal.
In conclusion, when shopping for a Plasma Television, make sure you check to see if it is an EDTV or an HDTV. Currently, most Plasma Televisions priced below $1,500 are of the EDTV variety, but there may be exceptions. Of course, this will change as prices come down for Plasma televisions in the coming year(s).
