Understanding HDTV Picture Resolution

!±8± Understanding HDTV Picture Resolution

Lets cut to the chase. The reason you bought an HDTV or the reason you are planning to get an HDTV is for the picture quality. That's why it's called high definition in the first place is my guess, for high definition picture. But do you really understand what a high definition picture is ? And what is the difference between a TV that displays in high definition and a disk or program that broadcasts high definition images ? This article will explain some of the jargon and help you to differentiate between HDTV and ordinary TV in terms of picture quality or resolution.

Picture resolution on a TV is described by the vertical resolution of the TV. The vertical resolution is the number of lines going from top to bottom that are displayed on the screen. To this extent if a TV has a vertical resolution of at least 720 lines then it is classed as an HDTV. Another measure of the picture resolution is the horizontal resolution. This is the number of lines going from left to right on the screen.

Many TVs, especially plasma and LCD TV's have what is called a fixed pixel display. TVs with older style cathode ray tube picture generation could alter the number of vertical and horizontal lines on a screen. With the new technology this is fixed. The main benefits of this are that each individual pixel is a separate entity that has it's own light and color displays. This lead to better clarity of the overall picture. Also the new TVs have a larger number of pixels on the screen than an ordinary TV. Pixel number in terms of resolution are determined by the number of horizontal pictures times the number of vertical pixels. Thus you might see in sales literature for the latest HDTV : picture resolution 1024 x 768. This is called the native resolution.

So the bigger the numbers the better ? In theory that's true but it also depends on what you are watching. If you are watching a television program that is using the NTSC standard for broadcast then the picture resolution will be around 330 x 480. If this program is being displayed on your HDTV with 1920 x 1080 picture resolution then the picture resolution will be degraded. Having the equipment to display HDTV is not the full picture, so to speak. You also need the media to get full benefit from your HDTV picture resolution. This means viewing HD television broadcasts or watching movies on the blu ray or HD DVD format of DVD.