thin film transistor liquid crystal display
TRANSCRIPT
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Thin film transistor liquid crystal display (TFT-LCD) is a variant
of liquid crystal display (LCD) which uses thin-film transistor (TFT)
technology to improve image quality (e.g., addressability, contrast).
TFT LCD is one type of active matrix LCD, though all LCD-screens
are based on TFT active matrix addressing. TFT LCDs are usedin television sets, computer monitors, mobile phones, handheld video
game systems, personal digital assistants, navigation
systems, projectors, etc.[1]
Contents
[hide]
1 Construction
2 Types
o 2.1 Twisted nematic (TN)
o 2.2 In-plane switching (IPS)
o 2.3 Advanced fringe field switching (AFFS)
o 2.4 Multi-domain vertical alignment (MVA)
o 2.5 Patterned vertical alignment (PVA)
o 2.6 Advanced super view (ASV)
3 Display industry
4 Electrical interface
5 Safety
o 5.1 Toxicity
6 See also
7 References
8 External links
[edit]Construction
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based s are by f ar t e st due t t eir l er roduction
cost, ereas olycrystalline silicon s are ore costly and difficult
to roduce[3]
.
[edit] ypes
[edit]Twisted em ti (TN)
N display under a icroscope, it
t
e transistors isible at t
e bottom
e not so expensi e t isted nematic display is t e most common consumer display type. e pixel response time on modern N panels
is sufficiently f ast to avoid t e shadow-trail and hosting ar tif acts of
ear lier production. he f ast response time has been emphasised in
adver tising N displays, although in most cases this number does not
reflect per f ormance across the entire range of possible color
transitions.[c it tion n
d d ]
More recent use of R Response ime
ompensation / Overdr ive) technologies has allowed manuf acturers
to significantly reduce grey-to-grey G2G) transitions, without
significantly improving the ISO response time. Response times are now uoted in G2G figures, with 4ms and 2ms now being
commonplace f or N-based models. he good response time and low
cost has led to the dominance of N in the consumer mar ket.[c it tion
n d d ]
N displays suff er f rom limited viewing angles, especially in the
ver tical direction. olors will shift when viewed off -perpendicular . In
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the vertical direction, colors will shift so much that they will invert past
a certain angle.
Also, most T panels represent colors using only six bits per B
color, or 18 bit in total, and are unable to display the 16.7 million color
shades ( -bittruecolor ) that are available from graphics cards.Instead, these panels display interpolated -bit color using
a dithering method that combines adjacent pixels to simulate the
desired shade. They can also use a form of temporal dithering
called Frame ate Control (F C), which cycles between different
shades with each new frame to simulate an intermediate shade. Such
18 bit panels with dithering are sometimes advertised as having "16.
million colors". These color simulation methods are noticeable to
many people and highly bothersome to some.[
]F C tends to be most
noticeable in dar er tones, while dithering appears to ma e theindividual pixels of the LCD visible. verall, color reproduction and
linearity on T panels is poor. Shortcomings in display
color gamut(often referred to as a percentage of the TSC 195 color
gamut) are also due to bac lighting technology. It is not uncommon
for displays with simple LED or CCFL-based lighting to range from
10% to 6% of the TSC color gamut, whereas other ind of displays,
utilizing more complicated CCFL or LED phosphor formulations or
B LED bac lights, may extend past 100% of the TSC color
gamut, a difference quite perceivable by the human eye.The transmittance of a pixel of an LCD panel typically does not
change linearly with the applied voltage,[5]
and the s B standard for
computer monitors requires a specific nonlinear dependence of the
amount of emitted light as a function of the B value.
[edit]In-plane switching IPS)
In-plane switching was developed by itachi Ltd. in 1996 to improve
on the poor viewing angle and the poor color reproduction of T
panels at that time.
[6]
Its name comes from the main difference fromT panels, that the crystal m lecules m ve parallel t the pa el pla e
i stea f perpe icular t it . This change reduces the amount of light
scattering in the matrix, which gives IPS its characteristic wide viewing
angles and good color reproduction.[7]
Initial iterations of IPS technology were plagued with slow response
time and a low contrast ratio but later evolutions have made mar ed
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improvements to these shortcomings. Because of its wide viewing
angle and accurate color reproduction (with almost no off-angle color
shift), IPS is widely employed in high-end monitors aimed at
professional graphic artists, although with the recent fall in price it has
been seen in the mainstream mar et as well.
Hitachi IPS evolving technology[8]
Name Nickname Year AdvantageTransmittance/contrast ratio
Remarks
Super TFT IPS 1996 Wideviewingangle
100/100 Base level
Most panels also support true 8-bit per channel color . These improvements came at the cost of a slower response time, initially about 50 ms. IPS panels were also
extremely expensive.
Super-IPS S-IPS 1998 Color shiftfree
100/137
IPS has since been superseded by S-IPS (Super-IPS, Hitachi Ltd. in 1998), which has all the benefits of IPS technology with the addition of improved pixel
refresh timing.
AdvancedSuper-IPS
AS-IPS 2002 Hightransmittance
130/250
AS-IPS, also developed by Hitachi Ltd. in 2002, improvessubstantially on the contrast ratio of traditional S -IPS
panels to the point where they are second only to some S-PVAs.
IPS-Provectus
IPS-Pro 2004 High contrastratio
137/313
The latest panel from IPS Alpha Technology with a wider
color gamut and contrast ratio matching PVA and ASVdisplays without off-angle glowing.
IPS alpha IPS-Pro 2008 High contrastratio
Next generation of IPS-Pro
IPS alphanext gen
IPS-Pro 2010 High contrastratio
Technology transfer from Hitachi to Panasonic
LG IPS evolving technology
Name Nickname Year Remarks
Super-IPS S-IPS 2001 LG Display remains as one of the main manufacturers of panels based on HitachiSuper-IPS.
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Advanced Super-IPS
AS-IPS 2005 Increased contrast ratio with better color gamut.
Horizontal IPS H-IPS 2007
Improves contrast ratio by twisting electrode plane layout. Also introduces an optional
Advanced True White polarizing film from NEC, to make white look more natural.
This is used in professional/ photography LCDs.
Enhanced IPS E-IPS 2009 Wider aperture for light transmission, enabling the use of lower -power, cheaper
backlights. Improves diagonal viewing angle and further reduce response time to 5ms.
Professional IPS P-IPS 2010 Offer 1.07 billion colours (30 -bit colour depth). More possible orientations per sub -
pixel (1024 as opposed to 256) and produces a better true colour depth.
[edit]Advanced fringe field switching AFFS)
This is an LCD technology derived from the IPS by Boe- ydis of
Korea. Known as fringe field switching (FFS) until 00 ,[9] advanced
fringe field switching is a technology similar to IPS or S-IPS offering
superior performance and colour gamut with high luminosity. Colour
shift and deviation caused by light lea age is corrected by optimizing
the white gamut, which also enhances white/grey reproduction. AFFS
is developed by YDIS TEC L IES C .,LTD, Korea (formally
yundai Electronics, LCD Tas Force).[10]
In 00 , YDIS TEC L IES C .,LTD licensed its AFFS patent
to Japan's itachi Displays. itachi is using AFFS to manufacturehigh end panels in their product line. In 006, YDIS also licensed its
AFFS to Sanyo Epson Imaging Devices Corporation.
YDIS introduced AFFS+ which improved outdoor readability in 007.
In ay 011, this technology is reported to be used in the next
generation Amazon Kindle eboo reader.[11]
[edit]Multi-domain vertical alignment MVA)
ulti-domain vertical alignment was originally developed in 1998
by Fujitsu as a compromise between T and IPS.[citati
!
!
ee"
e"
]It
achieved pixel response which was fast for its time, wide viewing
angles, and high contrast at the cost of brightness and color
reproduction. odern VA panels can offer wide viewing angles
(second only to S-IPS technology), good blac depth, good color
reproduction and depth, and fast response times due to the use of
TC ( esponse Time Compensation) technologies. When VA
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panels are viewed off-perpendicular, colors will shift, but much less
than for T panels.
There are several "next-generation" technologies based on VA,
including AU ptronics' P-MVA and A-MVA, as well as Chi ei
ptoelectronics' S-MVA. Analysts[w h
#
?]
predicted that VA woulddominate the mainstream mar et, but the less expensive and slightly
faster T overtoo it. The pixel response times of VAs rise
dramatically with small changes in brightness. Less expensive VA
panels can use dithering and F C (Frame ate Control).
[edit]Patterned vertical alignment PVA)
Patterned vertical alignment and super patterned vertical alignment
(S-PVA) are alternative versions of VA technology offered
by Samsung's and Sony's joint venture S-LCD. Developed
independently, they offer similar features to VA, but with higher
contrast ratios of up to 000:1.[citati
$ %
%
ee&
e&
]Less expensive PVA panels
often use dithering and F C, while S-PVA panels all use at least 8
bits per color component and do not use color simulation methods. S-
PVA also largely eliminated off angle glowing of solid blac s and
reduced the off angle gamma shift. Some newer S-PVA panels
offered byEizo offer 16-bit color internally .[citati
$ %
%
ee&
e&
], which enables
gamma and other corrections with reduced color banding. Some high
end Sony B AVIA LCD-TVs offer 10bit and xvYCC color support, for
example the Bravia X 500 series. PVA and S-PVA offer the best
blac depth of any LCD type along with wide viewing angles.[citati
$ %
%
ee&
e&
]S-PVA also offers fast response times using modern TC
technologies.
[edit]Advanced super view ASV)
Advanced super view, also called axially symmetric vertical
alig me t was developed by Sharp. It is a VA mode where liquid
crystal molecules orient perpendicular to the substrates in the off
state. The bottom sub-pixel has continuously covered electrodes,while the upper one has a smaller area electrode in the center of the
subpixel.
When the field is on, the liquid crystal molecules start to tilt towards
the center of the sub-pixels because of the electric field; as a result, a
continuous pinwheel alignment (CPA) is formed; the azimuthal angle
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rotates 3 degrees continuously resulting in an excellent viewing
angle. he ASV mode is also called PA mode.[ ' 2]
[edit] isplay industry
Thi ( secti) 0
is missing citations or needs footnotes. Please hel1
add i 2 li2 e citati3 2
s t 3 guard agai 2 st
copyr ight violations and factual inaccuracies. (December 2008)
Due to the very high cost of building f actor ies, there are f ew
ma jor OEM panel vendors f or large display panels. he glass panel
suppliers are as f ollows:
L4
D glass panel suppliers
Panel type
Company Remarksmajor TV
makers
IPS-Pro Panasonic
Solely for LC5
TV
markets and known asIPS Al pha TechnologyLtd.[13]
Panasonic,Hitachi,
Toshi6
a
7
-IPS
& P-
IPS LG Display
They also produceother type of TFT
panels such as TN for
OEM markets such asmobile, monitor,
automotive, por tableAV and industr ial
panels.
LG,Phili ps
S-IPS
Hannstar
Chuangwa Picture Tubes,
Ltd.
A-MVA AU Optronics
S-MVA Chi Mei Optoelectronics
S-PVA S-LCD (Samsung/Sony joint venture)
Samsung,
Sony
AFFS SamsungFor small and medium
si8 e special projects.
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AS9
Sharp Corporation
Solely for LCD TVmarkets
Sharp
Raw LCD TFT panels are usually factory-sorted into three categories,
with regard to the number of dead pixels, bac light evenness andgeneral product quality.
[citati @ A
A
eeB
eB
]Additionally, there may be up to +/-
ms maximum response time differences between individual panels
that came off the same assembly line on the same day. The poorest-
performing screens are then sold to no-name vendors or used in
"value" TFT monitors (for example, mar ed with letter V behind the
type number), the medium performers are incorporated in gamer-
oriented or home office bound TFT displays (sometimes mar ed with
the capital letter S), and the best screens are usually reserved for use
in "professional" grade TFT monitors (often mar ed with letter P or Safter their type number).
[edit]Electrical interface
External consumer display devices li e a TFT LCD feature one or
more analog V A, DVI, D I, or DisplayPort interface, with many
featuring a selection of these interfaces. Inside external display
devices there is a controller board that will convert the video signal
using color mapping and image scaling usually employing the discrete
cosine transform (DCT) in order to convert any video source
li e CVBS, V A, DVI, D I etc. into digital RGB at the native
resolution of the display panel. In a laptop the graphics chip will
directly produce a signal suitable for connection to the built-in TFT
display. A control mechanism for the bac light is usually included on
the same controller board.
The low level interface of ST , DST , or TFT display panels use
either single ended TTL 5V signal for older displays or TTL . V for
slightly newer displays that transmits Pixel cloc , orizontal
sync,Vertical sync, Digital red, Digital green, Digital blue in parallel.Some models also feature input/display enable, horizontal scan
direction and vertical scan direction signals.
ew and large (>15") TFT displays often use LVDS signaling that
transmits the same contents as the parallel interface ( sync, Vsync,
RGB) but will put control and RGB bits into a number of serial
transmission lines synchronized to a cloc whose rate is equal to the
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pixel rate. VDS transmits seven bits per clock per data line, with six
bits being data and one bit used to signal if the other six bits need to
be inver ted in order to maintain DC balance. ow uality displays
often have three data lines and theref ore only directly suppor t bits
per pixel, while better ones have a f our th data line so they can suppor t24 bits per pixel, which delivers truecolor . ltra high end models can
suppor t even more colors by adding more lanes, that s how 3 -bit
color can be suppor ted by five data lanes. Panel manuf acturers are
slowly replacing VDS with Internal DisplayPor t and Embedded
DisplayPor t, which allow sixf old reduction of the number of diff erential
pairs.
Backlight intensity is usually controlled by varying a f ew volts DC, or
generating a P M signal, or ad justing a potentiometer or simply fixed.
his in turn controls a high-voltage .3 kV) DC- AC inver ter or a matr ix of EDs. he method to control the intensity of ED is to pulse them
with P M which can be source of harmonic flicker .
he bare display panel will only accept a digital video signal at the
resolution determined by the panel pixel matr ix designed at
manuf acture. Some screen panels will ignore the SB bits of the color
inf ormation to present a consistent inter f ace bit->6bit/color x3).
laptop displays can't be reused directly with an ordinary computer
graphics card or as a television, this is because they lack a hardware
rescaler that can resi e the image to fit the native resolution of the
display panel.[c it C tion n
D D d D d ]
ith analogue signals like VGA, the display
controller also needs to per f orm a high speed analog to
digital conversion. ith digital input signals like DVI or HDMI some
simple reorder ing of the bits is needed bef ore f eeding it to the rescaler
if input resolution doesn't match the display panel resolution. or
CVBS V) usage a tuner and color decode f rom a uadrature
amplitude modulation QAM) to uminance Y), Blue-Y ), Red-Y
V) representation which in turn is transf ormed into Red, Green Blue
is needed.[c it C tion n D D d D d ]
[edit]Saf ety
This section requires expansion.
[edit]Toxi ity
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The liquid crystals inside the display are highly toxic to humans and to
the environment. It must not be ingested or come in contact with your
s in, eyes or clothes. If spills occur due to a crac ed display, wash off
immediately with soap and water.[1
E
] Liquid crystals currently
mar eted inside displays are generally non-toxic
[15]
.[edit]
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TFT stands for Thin-Film Transistor. TFT technology is a new standard these days for
manufacturing displays, monitors, laptop screens, and other devices. TFT LCD displays can
show crisp text, vivid colors, fast animations, and complex graphics.
TFT LCD monitors, also called flat panel displays, are replacing the old style cathode ray
tubes (CRTs) as the displays of choice. Almost all LCD monitors today take advantage of the TFT technology.
What are the benefits of a TFT display?
Each pixel on a TFT display is backed by a tiny transistor. Transistors are so small these
days, they need only a very minimal charge to control what they do. TFT displays are much
more energy eff icient than regular CRT screens that need a powerful light source.
TFT displays also allow for very f ast re-drawing of the display, so the image has very
little chance to flicker. This was not always the case with flat-panel monitors. Original
passive matrix LCD displays were not able to refresh at very high rates and therefore could
not keep up with fast moving images. A TFT monitor refresh rate is very high resulting in a
display that can be used for video, gaming, and all forms of multimedia.
A TFT monitor delivers crisp text, vibrant colors , and an improved response time for
multimedia applications. Today's standard for response rate in TFT monitors is 16 ms or
less.
H ow does TFT display work?
Let us start with explanation how a LCD display, a predecessor to TFT LCD, works.
In general, a LCD display comprises of a layer of LCD material and one or more polarizinglayers made of plastic, glass, or some other material. A LCD display has a sandwich-like
structure with liquid crystals filled between two glass (or plastic or polycarbonate) plates.
A LCD display shows a picture through millions of tiny picture elements called pixels. You
can understand a pixel as a tiny dot on your screen.
Pixels are formed by liquid-crystal cells that change the direction of light passing through
them in response to an electrical voltage.
These liquid crystals when stimulated by an external electrical charge can change the
properties of light passing through them. When you align two polarizing materials witheach other, light passes through. When you align one polarizing agent at a 90° angle to the
other, light is blocked. Change the voltage, and the amount of light passing through the
display is changed.
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Liquid crystals in LCD monitor act as a dynamic polarizing agent. They change their
orientation when you place a voltage across an LCD cell. The orientation of the polarizing
agent under the LCD layer either blocks or pass es light.
So, where does a TFT come into the game?
A TFT display is an advanced LCD display. A TFT monitor uses so -called thin-f ilm
transistortechnology to project a picture on the screen. Transistors in a TFT display are
used to change the orientation of the polarizing agent. A typical 17-inch TFT monitor has
about 1.3 million pixels and 1.3 million transistors. The following text explains TFT in a
greater detail...
Active or passive LCD?
When you look at a passive-LCD technology, the cells act as capacitors. When you charge acell, the liquid crystal flips to one position. When you stop supplying charge to the cell, it
voluntarily bleeds off its voltage and the liquid crystal slowly twists back to its original
position.
Passive LCD panels cannot quickly change the orientation of the crystal. Well, it is quick,
but not quick enough to display fast -moving graphics. To overcome this slowness,
engineers came up with active-LCD technology. Active-LCD displays use transistors to
actively change the orientation of crystals. That is where TFT comes from. T in TFT for
transistor. This method allows for faster control of the LCD cell but is also more complex.
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While passive-LCD displays start to blur with images moving faster than 8 to 15
frames/sec, TFT displays can display full-motion video and graphics because they use fast
switching transistors.
H ow is color displayed in a TFT monitor?
Now that we know how a LCD works and what it behind TFT, we can start talking about
color. Each pixel in a color TFT LCD i s subdivided into three subpixels . One of the subpixels
is capable of producing red, the other one green, and the last one bluecolor. Red, green,
and blue are the basic colors. Any other color can be produced by mixing up these three.
One set of RGB subpixels is equal to one pixel.
Because the subpixels are super tiny for the human eye to see them individually, the three
RGB elements appear to the human eye as a mixture of the three colors. Any color can beproduced by mixing these three primary color s.
Where does the light in a TFT LCD panel come from?
Old TFT displays and the small ones in simple applications such as calculators are ref lective
TFT. A reflective TFT display has no backlight. The polarizing agent at the rear of the TFT
display is simply a mirror layer behind the TFT panel. The agent merely reflects incoming
light from the front of the display. You need to be in a well -lit room to be able to read this
type of display.
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The next step in a TFT LCD design was to add a light source to it. More advanced TFT
displays have added sidelights or front lights to these displays. Sidelights and front lights
are virtually the same as backlights. The difference is just the position of the light. Front
lights sit on the side or slightly in front of the TFT layers. They are designed so that the light
they produce shines through the TFT panel and bounces off the reflective polarizing agent
back through the display.
A transmissive TFT uses a backlight. Most TFT LCD panels today are designed with
a backlight. The source of the light is mounted at the rear side of the LCD panel and shines
light towards your eyes through the TFT panel's polarizing medium (liquid crystal). Small
displays, such as cell phones or calculators, use light source that is placed along the sides of
the display.
The common TFT-display backlight is the CCFL (cold -cathode fluorescent lamp). CCFLs are
similar to fluorescent light tubes that you commonly find in offices and homes. Their
advantage is that they are small, inexpensive, replaceable, and cheap.
If the TFT display has its own light, why can't I see anything
on the display on a sunny day?
The polarizing medium in a TFT that transmits or blocks the backlight is clear, so any light
shining on the display from the front competes with the backlight. If the light source
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shining on the front of the TFT display is strong enough, such as sun on a sunny day, it
simply overpowers your laptop TFT display's backlight and the display image is washed out.
A reflective TFT display is usually a better choice for applications with high ambient light.
What is LED backlighting in a TFT LCD display?
If you shop for a laptop these days, the better ones come with LED backlight. In this case,
the source of light comes from LEDs instead of from CCFL.
LED technology has only recently achieved the white light necessary to illuminate these
panels. LEDs are the choice these days because they are stable over temperature ranges,
durable, and very energy efficient. That is why if you buy a laptop with a TFT LED b ack-
lighted display, it is possible that it will go for as much as 8 hours with your battery.
What else?
Perhaps you might be interested in some reading about LightScribe, ExpressCard, or USB
3.0 (Need for speed).
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T hin F ilm T ransistor is a variant of liquid crystal display (LCD) which uses thin-film transistor (TFT)
technology to improve image quality (e.g., addressability, contrast). TFT LCD is one type of active
matrix LCD, though all LCD-screens are based on TFT active matrix addressing.
Advantages of TFT displays over traditional CRT monitors:
There is much less glare from a TFT monitor. During testing in the Arts IT office we were able to have
the blinds open and still read the screen, something impossible with CR
T displays.The monitor is less bul
F
y. This has a couple of advantages, firstly it gives you more desF
space, but
secondly because of this you can position the monitor further away from you which we have found
more comfortable for the eyes.
TFT monitors produce less heat and radiation that CRT monitors.
TFT monitors have a very crisp image only comparable to very expensive CRT monitors.
The monitor (so long as it is VESA compliant) can be mounted on an arm or on the wall to save even
more desF
space.
Disadvantages of TFT displays:
If you are wor F
ing with graphics, although the graphics are very clear, due to the limited angle at
which you can view the display colours may appear slightly different on non-TFT screens. Web
authors beware.
Cost. A 15" TFT monitors costs approx £ G 50+vat for an unbranded/cheap model. A 17" CRT monitor
costs approx £1 H 0+vat.
TFT monitors have a limited angle of view. This is the angle at which you can clearly view the screen.
If you are looF
ing directly at the screen while wor F
ing on your PC this is fine, but if others are trying to
read it then they may have difficulty (try looF
ing at a laptop screen from a I 5 degree angle).
You may experience some blurring on lower end models when there is movement on the screen. This
is most prominent in full screen games where you get a motion blur effect but is also noticeable when
scrolling through documents or websites.
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TFT vs CRT monitor comparison
February 2, 2008 - 11:30 ² webmaster
Quite a lot of our customers these days go for TFT monitors when they buy their computers. Most
buy their TFTs because they look better than CRT monitors and because the price differentials are
much lower than what they used to be. We try our best to convey to our customers the differences
between CRTs and TFTs and the specific scenarios when one is better than the other. Some timeswe get through and some times we don't. Here we would like to bring out the differences between
the two types of monitors and their pros and cons.
Traditionally all computer monitors used to be CRT monitors which are quite similar to the CRT
televisions we have in our homes. LCD monitors were only used with laptops as the price
differences were quite high. However as technology advanced and the price differences between
CRTs and TFTs came down it became viable to sell computers with TFT (or LCD) monitors. The
display device in a CRT monitor is a cathode ray tube which is inherently bulky and power-thirsty
whereas the display device in a TFT monitor is a flat array of Thin Film Transistors which makes
the TFT monitors much smaller in size and also less power consuming.
The major differences between the two are
1) CRT monitors are bulky and consume a lot of table space where as TFT monitors are thin and
occupy less space.
2) TFT monitors are more easy on the eyes of the viewer than CRT monitors.
3) CRT monitors have much much faster response times than TFT monitors. Response time is the
time interval taken by a pixel on the screen to transit from the on state to the off state or reverse.
4) TFT monitors consume less power than CRT monitors. A typical 15" CRT monitor consumesabout 100W of power whereas a corresponding TFT monitor would only consume 30W of power.
5) TFT monitors looks more elegant than CRT monitors.
6) CRT monitors tend to have much better color responses than TFT monitors. In other words CRT
monitors display colors much better than TFT monitors.
Based on the above differences we can easily make certain deductions about the scenario's where
each of these types of monitors are ideal.
1) You save 70W when you use a 15" TFT monitor instead of a 15" CRT monitor. This would
translate to around 1 unit of electricity every 14 hours of usage. So depending on your usage
patter you can see how long it would take to break even on the cost differential through energy
savings. Say 1 Unit of energy costs 8 Rupees (approx 20 cents) and the cost differential is Rs 4000
(approx 100$) and you use your monitor for 10 hours every day, you will break even in around
700 working days. The equation used is simple; No of days for breaking even = ((Cost
Differential/Cost per unit)*14)/(Hours used per day). Based on your usage pattern and your
budget you can use the above data to make an educated decision.
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2) If you are a graphics artist and you require close to realistic representation of colors you will
have to go for a CRT monitor irrespective of any other factors.
3) If you are a gamer then depending on the type of games you play you will have to choose
between CRT and TFT monitors. If you play very fast moving games then response times of the
monitors comes into play and you might end up having to buy a CRT monitor to get a smoothgaming experience. If however you play more strategy games than action or racing games then
depending your other usage patterns you can decide between either a TFT or a CRT.
4) If you have to move your residence frequently as part of your job and you have to have a
desktop, then a TFT monitor would make more sense. It should be noted that a laptop would make
even more sense in such cases.
5) If you are running a software development center it might be wiser to select TFTs for your
software developers and CRTs for your graphics guys. If you are running any other kind of office
where your computers remain on most of the day then TFTs would pay for themselves in a few
years and would be the ideal choice.
6) If you are running a retail outlet a TFT would give your POS counter a more professional look
and also help you save on your electricity bills.
7) Small or restricted work areas also place a default preference of TFT monitors over CRT
monitors.
If you need help in deciding between a TFT monitor or a CRT monitor, do get in touch with us
using the comments form below and we will try to help you in making your decision.
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Q: What is a TFT?
A: Short for Thin Film Transistor, a type of LCD flat-panel display screen, in which each pixel is
controlled by from one to four transistors. TFT screens are sometimes called active-matrix LCDs.
Q: What are the benefits of a TFT display?
A: A TFT LCD display delivers crisp text, vibrant color and an improved response time for visual
applications at the best resolution of all the flat-panel techniques, but it is also the most expensive.
Q: What sets the TFT apart for other LCDs?
A: TFT displays use a separate tiny transistor for each pixel on the display. Because each transistor is so
small, the amount of charge needed to control it is also small. This allows for very fast re-drawing of the
display, as the image is re-painted or refreshed several times per second.
Q: What are the differences between TFT and Color STN?
A: TFT displays utilize active matrix technology and feature transistors on every pixel. Color STN (CSTN)
is a passive matrix graphic LCD with a color filter. It only has one transistor per each pixel row and
column and features a lower refresh rate than TFTs.
Q: What size TFTs does Microtips currently offer?
A: We currently offer a 2.4´, 2.8´, 3.5´, 4.3´, 5.7´ and 7.0´ TFT.
Q: How do I interface with a TFT?
A: 1st Pick a microprocessor with a built-in TFT controller (this will tell you which interface type to use)
2nd Determine which TFT size and interface type required
3rd Determine how the pins on the TFT should best connect to the corresponding pins on the your
microprocessor
4th Connect the FFC from the TFT to a mating connector mounted on your board which is assigned to
the TFT interface of the microprocessor
5th Write initialization code and software through your microprocessor to the TFT
Q: How does Microtips handle a fluctuating TFT supply chain? A: Microtips utilizes strategic partnerships with our supply chain and focuses on standard TFT sizes
(3.5´, 5.7´, and 7.0´).
Q: Who drives the TFT market?
A: The small TFT displays below 3.5´ are typically driven by the large volume cell phone manufacturers
in Asia. That being said the supply chain for TFT displays below 3.5´ can be more volatile than the 3.5´
and above sizes. The digital photo frame industry has also begun to affect the availability of the 7.0´ and
5.7´ sizes.