What is HDTV?

HDTV stands for High Definition TV and while the FCC does not have a standard definition for HDTV, it is widely agreed upon that HDTV is defined as having higher quality video, audio and a wider image aspect ratio than standard television broadcast signals.

HDTV is part of a larger set of standards called ATSC.

The FCC (Federal Communications Commission) has mandated that all licensed television stations be capable of broadcasting DTV by 2007.

To understand how much higher the quality HDTV is, you need to know the quality of standard TV. In the US, a standard TV has 525 scanned lines for each image. An image is refreshed every 30th of a second, however only half the image is refreshed every 30th of a second, so a full image is refreshed every 60th of a second. This format of refreshing an image is called interlaced. Progressive is when an image is refreshed in its entirety every 30th of a second. Out of the 525 lines of resolution that are scanned, only 480 lines are visible on the TV. Standard TV is also known as 480i (480 lines of usable resolution, interlaced).