3. Liquid crystals (LCs) are matter in a state which
has properties between those of conventional
liquids and those of solid crystals.
For instance, a liquid crystal may flow like a liquid,
but its molecules may be oriented in a crystal-like
way.
LIQUID CRYSTAL
4. LCD (Liquid Crystal Display)
• Liquid crystals were first
discovered in 1888, by
Austrian botanist Friedrich
Reinitzer.
• First experimental LCD by
RCA in 1968.
• Based on properties of
polarized light.
5. • LCD stands for Liquid Crystal Display.
• Liquid crystal between the TV's display panel.
• Liquid crystal gets activated on receiving
electric current.
• Uses fluorescent lights.
LCD
6. How LCD works
• Formed by two glass layers called substrates.
• One is in charge of columns, and the other is in
charge of rows.
• Liquid crystals are sandwiched in between these
two layers.
• Uses a grid to charge specific pixels.
• When this happens the crystals untwist and allow
light to pass through.
7.
8. A light-emitting diode (LED) is a two-
lead semiconductor light source. It is
a p–n junction diode that emits light
when activated.
When a suitable current is applied to
the leads, electrons are able to
recombine with electron holes within
the device, releasing energy in the
form of photons.
LIGHT EMITTING DIODE
9. LED, which stands for “light emitting diodes,” differs
from general LCD TVs in that LCDs use fluorescent
lights while LEDs use those light emitting diodes.
Also, the placement of the lights on an LED TV can
different.
The fluorescent lights in an LCD TV are always
behind the screen.
But, On an LED TV, the light emitting diodes can be
placed either behind the screen or around its edges.
HOW LED WORKS
10.
11. What is Plasma?
• In physics and chemistry , plasma is a state of
matter similar to gas in which a certain
portion of the particles are ionized.
12. Plasma Displays
• 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 electricall
y charged ionized ga
A Plasma T.V
13. Plasma Displays
• Invented at the University
of Illinois at Urbana-
Champaign in 1964 for the
PLATO Computer System
• 1983 IBM introduced 19”
orange on black
monochrome.
14. How Plasmas work
• Made up of tiny fluorescent
lights.
• Each pixel contains a red,
green, and blue light.
• xenon and neon gas is
contained in hundreds of
thousands of cells positioned
between two plates of glass
along with electrodes.
• When charged, it releases
ultraviolet photons which act
with the phosphors.
• This brings their energy level
up, when it goes back down it
is released as visible light
photons.
15. Comparison
POINTS LCD LED PLASMA
Advantages • More efficient
use of electricity
than CRT
• Produce little
glare compared to
plasmas
• Largest screen
sizes than other
flat panels
• Best for bright
rooms
• Biggest seller
• Very bright
• Very thin and
light
• Low power
consumption
• Best for dark
rooms
• Best blacks
• No motion blur
• Flat panel
• Great range of
larger sized
screens.
• Large viewing
angles.
16. Disadvantages • Manufacturers
often reject about
40 % of the
panels that come
off the assembly
line
• Color contrast
is not the best
• Poor viewing
angles
• Not very good
blacks
• Motion blur on
lower end models
• Backlight
uniformity issues
• Limited
viewing angle
• Quite
expensive.
• As it's slimmer,
you lose sound
quality.
• Not suitable for
rooms with
windows
• Occasional
temporary image
retention
• Bulkier
• Slight buzzing
noise
• Susceptible to
phosphor burn-in
17. Average Viewing
angle
Good Good Best
True Black
Level
Average Good Good
Daylight
Viewing
Good Good Average
Colors Good Good Best
Motion Blur Good Good Best
Average Cost for
40"
645$ 450$
Longevity Best Best Good
Average Yearly
Electricity Cost
for 40"
Best Best Good
18. Average
Thickness
1.8" 2.5" 2.5"
Average Weight
for 40"
27 lb 42 lb 42 lb
Light output
(brightness)
Best Best Good
Contrast ratio Good Good Best
Resolution Best Best Good
