Well as we keep on saying that we want to simplify technology for you . You don’t need to be ashamed when you go to your TV showroom or to purchase any gadget and salesman come up with words such as 780p , 1080p etc . We would simplify the jargon for you.
The numbers above are actually summed up resolution and scanning techniques used.There are three main things that define the quality when it comes to new High Definition TV (HDTV)
1). Frame size in pixels is defined as number of horizontal pixels × number of vertical pixels, for example 1280 × 720 or 1920 × 1080. Often the number of horizontal pixels is implied and thus omitted from text. So saying 720P or 1080I actually refers to the number of vertical pixels with the scanning method.
2).Scanning method is identified with the letter ‘I’ for interlaced scanning or ‘P’ for progressive scanning.Interlaced scan-based images uses techniques developed for Cathode Ray Tube (CRT)-based monitor displays, made up of 576 visible horizontal lines across a standard TV screen. Interlacing divides these into odd and even lines and then alternately refreshes them at 30 frames per second. The slight delay between odd and even line refreshes creates some distortion or ‘jaggedness’. This is because only half the lines keeps up with the moving image while the other half waits to be refreshed.
Progressive scanning, as opposed to interlaced, scans the entire picture line by line every sixteenth of a second. In other words, captured images are not split into separate fields like in interlaced scanning thereby there is no flickering also.
Now for understanding the above terminology ,we need to understand what difference they actually makes.The chart below elaborates it.
What the chart shows is that, for a 50-inch screen, the benefits of 720p vs. 480p start to become apparent at viewing distances closer than 14.6 feet and become fully apparent at9.8 feet. For the same screen size, the benefits of 1080p vs. 720p start to become apparent when closer than 9.8 feet and become full apparent at 6.5 feet. In my opinion, 6.5 feet is closer than most people will sit to their 50″ plasma TV (even through the THX recommended viewing distance for a 50″ screen is 5.6 ft). So, most consumers will not be able to see the full benefit of their 1080p TV