What are the difference between raster scan system and random scan system?

Answer 1

Raster-scan system:-1)raster displays have less resolution.

2)the lines produced are ziz-zag as the plotted values are discrete.

3)high degree realism is achived in picture with the aid of advanced shading and hidden surface technique.

4)decreasing memory costs have made raster systems popular.

5)In this case, the electron beam is swept across the screen, one row at a time from top to bottom.

6)Picture definition is stored in a memory area called the refresh buffer/frame buffer.

7)Refreshing on raster scan displays is carried out at the rate of 60 to 80 frames/second.

Random scan system:-1)random displays have high resolutions since the picture definition is stored as a set of line drawing commands and not as a set of intensity values.

2)smooth lines are produced as the electron beam directly follows the line path.

3)realism is difficult to achieve.

4)random-scan system's are generally costlier.

5)Here CRT has the electron beam directly only to the parts of the screen where a picture is to be drawn.

6)Picture definition is stored as a set of line drawing commands in an area of memory referred to as refresh display file.

7)Random scan systems are designed to draw all the component lines of a picture 30 to 60 times each second.