Transcript LCD Television Technology

LCD Television Technology
By Brian Sheskier
What is an LCD Television?
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Liquid Crystal Diode
LCD’s used widely, such as in microwaves
and calculators
The twisted nematic (TN) is the most
common liquid crystal used in LCD
televisions today
Brief LCD History
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Liquid crystals were
discovered by Austrian
botanist Friedrich Reinitzer
in 1888
Melted cholesterol
benzoate, noticed it became
a cloudy liquid then cleared
up as temp. rose
The liquid turned blue before
crystallizing as it was cooled
Twisted Nematic Liquid Crystal
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Used in most display applications today,
such as LCD televisions and LCD monitors
Has a naturally crystalline structure
Reacts to electric currents in particular ways,
usually by untwisting to different degrees
depending on the voltage of the current it is
exposed to
“Liquid” Crystal
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Liquid in the sense of the crystals twistability
and relative pliability in reaction to the
voltage of the current it is exposed to
How do LCD TV’s Work?
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Work by blocking light
Sandwich a solution of TN liquid crystals
between two perpendicularly aligned sheets
of polarized glass
the intensity of the light is manipulated as it
passes through this structure and out the
other glass panel at the other end
How LCD’s Work Cont.
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Liquid crystals then untwist depending on the
voltage of electrical charge passing through
them
Intensity of light able to pass through second
glass pane is affected
Display can switch between light and dark
states
Light State/Dark State
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Light State- A state of
the display where the
liquid crystals are fully
twisted
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Dark State- A state of
the display where the
liquid crystals are
completely untwisted
Pixels
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Tiny segments that make up the LCD display
Manipulated to present information or form
images for viewing
Pixel Structure
Addressing
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The process in which
pixels are turned off
(allowing the passage
of light) and on (not
allowing the passage of
light)
Creates the image on
the display for the
viewer
Pixels Switched Off
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Pixels Switched On
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Color
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Each pixel is divided into 3 sub-pixels: blue,
red, and green
These sub pixels work together to produce
the overall hue of the LCD’s pixel
16.8 million colors in total
Advantages of LCD TV’s
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Brighter and have higher contrasts than other
TV’s (no glare)
160-degree viewing angle
High dot pitch = sharper and more realistic
image
Cooler running temperature
No static images are burned in
Advantages Cont.
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Wide and colorful image
High response time- time it takes a pixel to
refresh itself, which makes the image appear
smoother and not jerky
Long Life
Multi-uses- HDTV, regular TV, home video,
any video format is accepted
Disadvantages
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Tracking motion isn’t as good as Plasma
Lower contrast ratio
More expensive than Plasmas
Not common over 42-inches
Does anyone know how big the world’s
largest LCD TV is?
Largest LCD TV
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Largest LCD TV is 108”
Introduced by Sharp at an electronics show
in Las Vegas
Two Links to Outside Websites
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http://electronics.howstuffworks.com/lcd5.htm
http://hometheater.about.com/od/lcdtvfaqs/f/l
cdfaq2.htm
Model
MSRP
1
Sharp LC-37G4U
$5,999
2
Sharp LC-32G4U
$4,499
3
Toshiba 32HL83P
$4,499
4
Sony KLV-23HR2
$2,699
5
Panasonic TC-32LH1
$4,499
6
Sharp LC-20B4U-S
$2,199
7
Toshiba 26HL83P
$3,299
8
Sharp LC-26GA4U
$3,299
9
JVC LT-26WX84
$2,999
10
Sony KLV-30XBR900
$4,999
References
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www.about.com
www.howstuffworks.com
www.plasmatvbuyingguide.com
www.wikipedia.org