In the present market scenario where innumerable types, models, brands and shapes of television sets are getting introduced and offered for sale, the consuming public crave to learn about the differences between them. Media advertisements and catalogues give vivid description about them. Many of the technical terms or jargons are heard, explained and discussed by the consumers in their bid to understand clearly about the products before buying them. Internet is the best source for the layperson to gather valuable information about the form and content of any particular product.
Among many terms that are used in the context of television technology, 1080i and 1080p are referred very frequently. What is understood vaguely is that they are technical specification concerning high definition flat screen television. Going deeper into the subject, it is pointed out that both the high definition formats offer identical information. Both represent a 1920 x 1080 pixel resolution, i.e.1920 pixels across the screen and 1080 pixels down the screen. Differences occur in the way the signals are emitted from the source or received at the other end – in the case of television the receiving end being the display screen.
In 1080i each frame of video is displayed alternatively. The field contains 540 rows of pixels from top to bottom of the screen. Odd fields will be displayed first followed by even fields and both together constitute a full frame of 1080 pixel rows. A single display takes place once in every 30th of a second. As the frames are displayed intermittently, it is known as 1080i. The alphabet ‘i’ stands for interlaced.
As far as 1080p is concerned each frame is displayed progressively or sent together, and the word ‘p’ denotes progressive scan. It is displayed in three different speeds. Most common system is 1080p/60 in which same frame is repeatedly sent once in every 30th of a second. It is known as enhanced video frame rate. The second system is 1080p/30 wherein the frame is displayed once in every 30th of a second which is called recorded video frame rate. The third system in which the display takes place once in every 24th of a second is known as standard motion picture film frame rate.
The consumer has to assess the quality of display by watching the performance. In case of inadequacies or blemishes, the matter should be brought to the attention of the manufacturer. In some models of HD TVs the process is done internally. The interlaced scanning was adopted traditionally, but when it comes to High Definition TV, desktop computers and other sophisticated products progressive scan is best suited. The manufacturers incorporate progressive scanning in large screens and flat panel televisions as the traditional interlaced scan is not effective in them.
