Display Devices

Question 1

Liquid Crystal Display

LCD

Answer 1

-Light shines through crystals

• Liquid crystal molecules sit between two polarizing filters
  
  • Turn the molecules & light passes
• Requires some type of backlight
  
  • Light shines through the LEDs

Question 2

TN vs IPS

Answer 2

• TN (Twisted Nematic) - LCD most common
  
  • Fast response time (gaming)
  • Low power draw
  • Poor viewing angles - color shifts
• IPS (In Plane Switching) LCD
  
  • Excellent color representation
  • No tailing when touched - mobile devices
  • More Expensive

Question 3

Fluorescent vs, LED Backlighting

Answer 3

• CCFL - Cold Cathode Fluorescent Lamp
  
  • Higher voltage & power needed
  • Used invertor for DC to AC power
  • No longer common backlight
• LED - Backlight LCD display
  
  • LEDs around the edge of the screen
  • An array of LEDs behind the screen
    - May be dimmed individually

Question 4

Plasma Display

Answer 4

• A Display of tiny cells - Noble gas & Mercury
• Voltage forms a plasma
• UV light strikes colored phosphor
• Deep blacks, fast response time
  
  • Very good color representation

-No longer in active production

Question 5

Digital Projectors

Answer 5

-Not always LCD - But most common

• Metal - halide lamp
  
  • Very hot, very bright light
  • Expensive
• Always let bulbs cool
  
  • Fam will run after shutting off
  • Keep plugged in

Question 6

Organic Light Emitting Diode

OLED

Answer 6

• Organic compound emits light when receiving electrical current.
• Thinner & lighter
• No backlight - Organic compound provides light
• Lifespan can be shorter than LED