What is different between a progressive scaned and none progressive sacned image?

Do they effect on the image quality or not. Or is the the progressice scan effective in all tvs?

Progressive scan creates a complete image in one field (1/60 sec in the US) by displaying every line one after the other. The other method, called interlace, takes two fields to complete an image; the first field displays only every other line (the odd-nombered lines, e.g.), and the second field displays the remaining lines. Interlace scanning was used when television was first developed to reduce the required bandwidth needed to transmit the signal. For images that are stationary or slow-moving, your eye retains the image of the first field while the second field is being displayed, so you have the illusion of a complete picture with all the scan lines.

There are two problems with interlacing: 1) fast-moving objects will contain only half the number of lines in any position and will suffer loss of resolution. Edges of moving objects will appear jagged. 2) Cathode ray tube (CRT) displays have difficulty keeping the spacing between the two sets of lines exactly right. This is especially noticeable in text images (even stationary ones) and this is the reason that computer monitors are always progressive scan, and have been from the early days.

New TV sets have gone away from CRTs and use "fixed pixel" displays such as plasma, LCD or DLP. All of these displays are progressive scan; program material that is interlaced is converted to progressive by the electronics in the TV. Progressive is 1 full video frame every 1/30th of a second.