What is the difference between progressive and interlaced scanning?
Each frame that makes up a TV image is created by an electron beam that rapidly scans horizontally across the face of your TV screen, from top to bottom. With interlaced scan, the beam alternately scans the odd-numbered lines and then scans the even-numbered lines. Today’s conventional TV broadcasts use the interlaced scanning method (up to 525 scan lines per frame). With progressive scan, all the lines are scanned at once, progressing from the top to the bottom of the frame, in one quick burst. The perfect still image generated for each frame in progressive scanning results in better rendition of moving subjects. HDTV standard broadcast formats are 1080i (1080-line interlaced scan) and 720p (720-line progressive scan).
