3. Cathode ray tube
Cathode-Ray Tube or CRT (sometimes called the Braun Tube) has
played an important part in displaying images, movies, and
information
The cathode ray tube or (CRT) is a vacuum tube containing one or
more electron guns usually three red, green and blue (a source of
electrons or electron emitter) and a fluorescent screen used to view
images.
cheap to manufacture and the ability to display high quality
images.
5. 1. Three Electron guns (for red, green,
and blue phosphor dots)
2. Electron beams
3. Focusing coils
4. Deflection coils
5. Anode connection
6. Mask for separating beams for red,
green, and blue part of displayed
image
7. Phosphor layer with red, green,
and blue zones
8. Close-up of the phosphor-coated
inner side of the screen
6. ADVANTAGES
High contrast ratio (over 15,000:1), excellent colour, fairly
wide colour gamut and low black level.
No native resolution; the only current display technology
capable of true multisyncing
No input lag.
Near zero color, saturation, contrast or brightness
distortion.
Excellent viewing angle.
Allows the use of light guns/pens.
7. DISADVANTAGES
» Large size and weight, especially for bigger screens (a 20-inch (51 cm)
unit weighs about 50 lb (23 kg)).
» Geometric distortion caused by variable beam travel distances.
» High power consumption. On average, a CRT monitor consumes 2–10×
the power that an identically sized LCD monitor would consume,
depending on the type of backlight used in the LCD screen, and its
brightness setting.
» A lot of heat can be emitted during operation, due to relatively high
power consumption.
» Sensitive to magnetic interference, which can cause the image to
shimmer or the colors to shift.
8. LCD
» Liquid crystals were first discovered in 1888.
» A liquid-crystal display better known as (LCD) is a flat
panel display, electronic visual display, or video display
that uses the light modulating properties of liquid
crystals. Liquid crystals do not emit light directly.
» The LCD screen is more energy efficient and can be
disposed of more safely than a CRT .
10. Figure:
1. Polarizing filter film with a vertical
axis to polarize light as it enters.
2. Glass substrate with ITO electrodes.
3. Twisted nematic liquid crystal.
4. Glass substrate with common
electrode film (ITO) with horizontal
ridges to line up with the horizontal
filter.
5. Polarizing filter film with a
horizontal axis to block/pass light.
6. Reflective surface to send light back
to viewer. (In a backlit LCD, this layer is
replaced with a light source.)
11. Passive and active-matrix
Passive matrix
Active Matrix
Twisted nematic (TN)
Vertical alignment (VA)
Blue phase mode
13. » Very compact and light.
» Low power consumption.
» Very little heat emitted during operation, due to low power
consumption.
» The possible ability to have little or no flicker depending on
backlight technology.
» Is very thin compared to a CRT monitor.
» Emits much less undesirable electromagnetic radiation than a CRT
monitor.
» Can be made in almost any size or shape.
» Can be made to large sizes (more than 24 inches) lightly and
relatively inexpensively.
Advantages
14. » Limited viewing angle.
» Uneven backlighting in some (mostly older) monitors, causing
brightness distortion, especially toward the edges.
» Dead or stuck pixels may occur during manufacturing or through
use.
» Poor display in direct sunlight, often completely unviewable.
Cannot be used with light guns/pens.
» Hard to read when wearing polarized sunglasses.
Disadvantages
15. » A plasma display panel (PDP) is a type of
flat panel display common to large TV
displays 30 inches (76 cm) or larger.
» They are called "plasma" displays
because the technology utilizes small
cells containing electrically charged
ionized gases, or what are in essence
chambers more commonly known as
fluorescent lamps.
» Plasma displays are bright (1,000 lux or
higher for the module), have a wide
color gamut, and can be produced in
fairly large sizes—up to 3.8 metres (150
in) diagonally
PLASMA
17. Advantages
» Picture quality
» Capable of producing deeper blacks allowing for
superior contrast ratio
» Wider viewing angles than those of LCD; images do
not suffer from degradation at high angles like LCDs
» Less visible motion blur,very high refresh rates and a
faster response time, contributing to superior
performance when displaying content with
significant amounts of rapid motion.
18. Disadvantages
» Screen-door effects (black lines between rows of pixels) become
noticeable on screen sizes larger than 127 cm (50 in); the effect
is more visible at shorter viewing distances.
» Uses more electrical power, on average, than an LCD TV.
» Plasma displays are generally heavier than LCD, and may require
more careful handling such as being kept upright.
19. NEW DISPLAY TECHNOLOGIES
• Traditional LCD displays use a cold-cathode
fluorescent lamp (CCFL) as the light source behind the
LCD layer.
• LCD display technology is getting more refined with
each passing year. LCD displays are low-cost,
lightweight and can produce excellent images, and
new LCD developments such as In-Plane Switching
(IPS) promise to give LCD displays much wider viewing
angles and better visibility in bright light.
• OLED,LED BACKLIT,IPS
20. OLED
Working
Figure: Schematic of a bilayer OLED: 1. Cathode (−), 2. Emissive Layer, 3.
Emission of radiation, 4. Conductive Layer, 5. Anode (+)
23. Advantages
• Lower cost in the future
• Lightweight and flexible plastic
substrates
• Wider viewing angles and improved
brightness
• Better power efficiency and thickness
• Response time
31. Super PLS
» Further improvement in viewing
angle
» 10 percent increase in brightness
» Up to 15 percent decrease in
production costs
» Increased image quality
» Flexible panel
32. Advantages
» IPS panels display consistent, accurate color from all viewing
angles
» Unlike TN LCDs, IPS panels do not lighten or show tailing when
touched. This is important for touch-screen devices, such as
smartphones and tablets.
» IPS panels can process high speed signals without data loss by
using copper wiring with low resistance values.
» IPS panels offer clear images and stable response time.
33. Disadvantages
» IPS panels require up to 15% more power than TN displays.
» IPS panels are more expensive to produce than TN displays.