What is the difference between square and non-square pixels? Should this be a decision factor in my purchase?
Pixels are the basic picture elements of digital display devices such as plasmas. Pixels are further divided into three different ?sub-pixels? regions for each Red, Green and Blue fundamental color spaces.
The pixel structure itself can take various shapes. There are different manufacturing techniques to produce plasma panels of large group of pixels. The majority of manufacturers OEM their panel glass to Panasonic who uses ?square? pixel structure. This type of panel has the correct physical and image ratio. For example, a 16:9 physical ratio will also have 16:9 pixel ratio (a typical 50? unit will have 1365:768 pixels +/- 2-3 pixels).
On the other hand, all Pioneer 50? panels (1280:768) and the new generation of HD 42? panels (1024:768) have a ?rectangular? pixel structure. While keeping the same 16:9 physical ratio, the rectangular pixel structure mismatches the physical ratio by 15:9 for the 50? plasmas and 12:9 for the HD 42? units. This translates into a ?stretched? image to fill the correct 16:9 physical ratio (circles look like ovals). However, the internal scaling processing of the plasma units compensate for this and the end result is a perfect image (circles look circles).