Interlaced scan is one of two methods used for "painting" an image on a
television screen (the other being
progressive
scan). Designed for the analog
NTSC television
system, interlaced scanning uses two fields to create a frame. One field contains all the odd lines in the image, the
other contains all the even lines of the image. A television scans 60 fields
every second (30 odd and 30 even). These two sets of 30 fields are combined to
create a full frame every 1/30th of a second, resulting in a display of 30
frames per second. Drawbacks to
interlaced scanning compared to progressive scanning include
flicker, lower
resolution and quality issues.
Compare with progressive scan.
