1. 10/19 Monitors CRT monitors: Flat-panel displays Electron guns
Phosphors
Shadow Masks
varieties
Raster
scan lines
field
Flat-panel displays

2. 2A: How many colors are there?
Name colors possible mode
Standard VGA bit
256 color mode bit
High Color 65, bit
True Color 16,777, bit
VGA: Video Graphics Array
SVGA: Super VGA
XGA: Extended Graphics Array

3. 3. Sending it to the monitor
3 electron guns
RED, GREEN, BLUE
CRT: “Cathode Ray Tube”
video card’s signals tell the intensity needed for each gun

4. 4. The magnetic yoke
The magnetic deflection yoke bends the electron beams from the guns.
Think of the electron guns as the gas pedal
and the magnetic yoke as the steering wheel

5. 4A. Terms Resolution: # pixels displayed horizontally and vertically
Refresh rate: how quickly the image is redrawn

6. 5. The Shadow Mask
Purpose: to keep the electron beams sharp and on target.

7. 5. The Shadow Mask: Types
Dot pitch: distance from one hole’s center to another.

8. 5. The Shadow Mask: Types
Aperture Grille: “Stripe Pitch” -- distance from center of column to the next.

9. 5. The Shadow Mask: Types
Slot Mask: “Stripe Pitch” -- distance from center of column to the next.

10. 6. The Phosphors Material that glows. Different type for each color.
“Persistence”: phosphor keeps glowing after electron beam leaves.

11. 7. Raster scanning
Raster: the area that is hit by the electron beams, line by line. Each line is called a scan line.
Field: a complete sweep of the screen.
Refresh: rate usually at least 60/sec (60 Hz)

12. 9. The cheap way out. “Interlacing”: scan every OTHER line.
Can be seen sometimes as a flicker.

13. Flat-panel LCD Displays
Passive-matrix vs. Active-matrix
Resolution limitations
Considerably more expensive than CRTs
image courtesy of Viewsonic.com

14. Flat-panel Plasma Displays
Brighter than LCD
Easier to manufacture (theoretically)
Mainly used for large-scale applications
image courtesy of Viewsonic.com