Raster CRT

Advantages

o   Allows solids, not just wireframes

o   Leverages low-cost CRT technology (that means., TVs)

o   Bright, i.e. display emits light

Disadvantages

o   Requires screen-size memory array

o   Discreet sampling (pixels), that means the lines are not straight anymore as in random scan display device. Now ,the lines consist of pixels that can lead to jig jag

o   Practical limit on size (call it 40 inches)

o   Bulky

o   Finicky (convergence, warp, etc.).

However, portable computers such as notebooks employ liquid crystal displays (LCDs) which are also raster devices. The screen should be refreshed to maintain the displayed picture. Now, we are going to describe it in detail.