Which is better TFT screen : tn TFT vs IPS LCD display?
If comparing tft screen
in display performance, IPS LCD is better than traditional a-si TN tft lcd display in viewing angle and
color conversion, IPS is with higher contrast than TN tft lcd. If comparing in power
consumption, IPStft panel is higher around 15% than regular tft screen (TN display mode), if
comparing TN panel vs ips in cost, IPS lcd is higher around 30%~50% than ordinary TFT panel. In this article, we would introduce the differences for
IPS lcd and tft lcd in details.
To evaluate
the display performance, we have to evaluate from the key characters of tft display.
Instead of AMOLED or pm OLED display, lcd display is passive display, it can
not emit light by itself, it have to use light source for displaying, we call
it backlight, since we always use it as the light source on the back of LCD
display. So the lcd display module’s key characters is the viewing angle,
contrast, response time, brightness of the lcd module, NTSC (color saturation),
resolution. The brightness of lcd is mostly related to the backlight
brightness, and NTSC is related to the color filter of lcd, the resolution of
IPS lcd and tft lcd have no big difference, so we are mainly discuss the
viewing angle, contrast, response time and power consumption for IPS LCD vs TFT
in this article.
Why IPS LCD have a better viewing
angle than tn tft panel?
The reason is
the arraying ways of IPS LCD and tft lcd display, because the liquid crystal
elements planed in horizontal, it only switch on when power on, so the lights
would be blocked when we view it from difference direction. While for TN tft
lcd, its liquid crystal elements array in vertical, some of lights would be
blocked when we view it from difference directions, especially in wide viewing
angle, the color inversion would be happen. Please see the display effect in
difference viewing angle for IPS LCD vs tft lcd:
Viewing angle
of TFT LCD IPS vs tn TFT:
Viewing directions
IPS viewing
angle
tn TFT viewing
angle
6 o’clock
85°
65°
12 o’clock
85°
55°
3 o’clock
85°
65°
9 o’clock
85°
65°
IPS lcd , no
color inversion in all viewing angles （find more detail about 2.4" IPS TFT LCD）:
Which contrast is better? IPS vs TN tft panel
The contrast
of IPS LCD is better than tft lcd, why? Because as we mentioned on the upper,
IPS LCD is negative display mode, and the light can not transmit it when power
off, it would be more black when in display off,
the LCD
contrast value = the luminance of display on / the luminance of display off,
so TFT LCD IPS is
more easily to get the high contrast because it have more blacker background
when in power off. Because the high contrast on IPS LCD, so IPS lcd can be more
brilliant color image – this is a huge advance in technology than a Twisted
Nematic (TN) display.
IPS tft screen has better
color re-production than TN TFT LCD panel.
The display
response time: TFT LCD IPS vs TN TFT panel
Generally, IPS
have fast response time than TN TFT LCD, why? Because the liquid crystal
elements inside the IPS LCD is in plane, the IPS liquid crystal is switched in
one plane when power on, while TN TFT LCD’s liquid crystal is twisted when
power on, it need more time than the IPS LCD switched in one plane, that is the
reason why IPS TFT LCD have faster response time than regular tft lcd. A faster
response time for IPS LCD, it would improve the display “tail” especially when
the screen display in fast movement video.
IPS tft screen
TN TFT panel
Contrast
600:1
300:1
Response speed
0.3mS
10mS
viewing angle
Full
viewing angle 85°/85°/85°/85°
12:00/6:00 65°/55°/65°/65°
Side viewing
No change on color
Color
get dark and dim in wide viewing angle
The power
consumption: IPS vs TFT lcd panel
TN TFT LCD has
more than around 15% power consumption than IPS lcd. The reason still comes
from the array way of liquid crystal inside the IPS LCD. because the liquid
crystal elements are arrayed in the plane, the power would be save for
switching on liquid crystal in IPS than twist it in tft lcd, that is the reason
IPS screen is better than TN TFT lcd in power consumption.
Regarding the
IPS LCD have better contrast, but in the same time, it have less transmissive
ratio, so we need more light from lcd backlight, if used more led chips, so it
also need more power to the lcd backlight, so the total display module might
need more power consumption if the backlight driving current for IPS LCD. so we
need to more concern about the backlight current consumption instead of the IPS
tft panel itself. The main power consumption would be from the lcd
backlight, not the IPS tft panel.
Which cost is
better: IPS vs tn tft lcd?
The ips lcd
cost would be higher around 30%~50% than TN tft lcd, the main reason is less
tft lcd manufacturers are making IPS LCD, but the market is high demand, so the
ips lcd price is higher than tft lcd. on the other hand, the tft lcd production
technology is more mature than IPS LCD, it has a better production ratio than
IPS LCD.
Which is more
suitable for adding touch screen: IPS lcd vs TFT?
If adding the
resistive touch screen, there would be no a big difference for IPS lcd or tft
screen. If adding the capacitive touch with frame bonding, that is capacitive
touch joint the lcd screen via glue tape on the lcd frame, there would be a gap
of air layer between the capacitive touch and lcd, if in this way, it still no
big difference for IPS LCD screen and TFT.
But if the
capacitive touch with the lcd screen in optical bonding, that is full joint
between the lcd screen and capacitive touch, IPS lcd screen would be better than TN
tft lcd screen, because tn tft screen would be more easily to create “ripple”
when touch on the capacitive touch screen, the reason is still comes from the
liquid crystal elements array mode.
What is IPS LCD screen?
IPS (In-Plane Switching) lcd is still a type of TFT LCD, IPS TFT is also called SFT LCD (supper fine tft ), different to regular tft in TN (Twisted Nematic) mode, the IPS LCD liquid crystal elements inside the tft lcd cell, they are arrayed in plane inside the lcd cell when power off, so the light can not transmit it via the IPS lcd when power off, When power on, the liquid crystal elements inside the IPS tft would switch in a small angle, then the light would go through the IPS lcd display, then the display on since light go through the IPS display, the switching angle is related to the input power, the switch angle is related to the input power value of IPS LCD, the more switch angle, the more light would transmit the IPS LCD, we call it negative display mode.
What is tn tft lcd?
The regular tft lcd, it is a-si TN (Twisted Nematic) tft lcd, its liquid crystal elements are arrayed in vertical type, the light could transmit the regular TFT LCD when power off. When power on, the liquid crystal twist in some angle, then it block the light transmit the tft lcd, then make the display elements display on by this way, the liquid crystal twist angle is also related to the input power, the more twist angle, the more light would be blocked by the tft lcd, it is tft lcd working mode.
A TFT lcd display is vivid and colorful than a common monochrome lcd display. TFT refreshes more quickly response than a monochrome LCD display and shows motion more smoothly. TFT displays use more electricity in driving than monochrome LCD screens, so they not only cost more in the first place, but they are also more expensive to drive tft lcd screen.The two most common types of TFT LCDs are IPS and TN displays.
Why needs an IPS tft screen:
If you use your screen for creative purposes, to watch movies, video, or
mount the screen on the wall that need to view it in all viewing angle, you' may think, do i need an IPS tft screen? the answer would be " yes", you need an IPS for getting the best viewing angles and color accuracy. because IPS LCD is
170 degree wide viewing angle, people could see the display image without the
color shift.
Maclight IPS tft screen:
Maclight
display ( www.szmaclight.com) is offers off-the-shelf
Color TFT display technologies in both TN and IPS, the sizes have 2.4”, 2.8”
3.5” ,4.3”. 5” 7”, 10.1” IPS LCD and tft lcd module, Maclight has the ability
to modify LCDs to meet your unique needs.
0.96" IPS lcd display module: ==>( click the picture to check more)
0.9 inch ips tft lcd display module
80x160 dots tft lcd
suitable for wearable display
IPS full viewing angle tft display
ST7735S controller ic
4 wires spi interface.
1.54" square IPS lcd module: ==>
240x240 dots IPS tft lcd
suitable for wearable display
capacitive touch screen optional
1.54'' square lcd display, ips tft display panel
ST7789 controller ic, MCU interface
2.4" IPS LCD screen: ==>
full viewing angle tft lcd
high contrast tft display
touch panel screen optional
240RGBx320 resolution 2.4' tft.
2.6" IPS LCD TFT: ==>
240RGBX320 dots ips tft
Full viewing angle
ILI9341 IC drive
MCU/SPI/RGB interface
2.8" IPS TFT screen:==>
240RGBX320 dots ips tft
full viewing angle tft lcd
touch panel screen optional tft display
ST7789V controller ic,
MCU/SPI/RGB interface
3.5" IPS LCD module-Landscape type: ==>
QVGA 320RGBX240 dots tft lcd
Free viewing angle tft display
High brightness tft, sunlight readable, 800 nits
ST7272 driver,
RGB interface,
resistive and capacitive touch screen optional.
3.5" IPS LCD module-Portrait type: ==>
320RGBx480 dots
SPI/RGB/MCU interface
ILI9486L driver ic
4.3" ips lcd module: ==>
800RGBx480 dots
wide temperature
Free viewing angle
HX8264-E & HX8664-B driver ic,
RGB interface
5.0" ips lcd capacitive touchscreen: ==>
Wide temperature tft , -30~80 degree working temperature
Full viewing angle
800x480 pixel
Capacitive touch screen and resistive touch optional
Sunlight readable high brightness backlight optional
TFT technology IPS & TFT Display panel Features
Before we go
into the differences, let’s talk about features of each technology. Note that
we’re not talking TVs, computer, or tablets, but screens on a much smaller
scale, (think 7” or smaller) which uses different rules to fit that scale.
First, it’s interesting to discover that the TFT display technologies is the
most common type of color display technology; more monochrome displays still
out-sell color, due to lower cost and lower power consumption, however, the
narrow poor visibility of TFTs in direct sunlight is their downside; but I’m
getting ahead of myself here.
IPS technology
has come a long way in regards to cell phones and other LCD screens that are
even much smaller. (Picture digital clocks on a radio, microwave, and hand-held
games) Some of the features of an TFT LCD IPS screen include:
Wider viewing angles – crystals are
aligned horizontally rather than vertically, so it allows for better
angled viewing, perfect for smaller screens, where you need to rotate the
screen for better viewing
Lower power consumption, resulting in
longer battery life – again for smaller screens, this works great, because
even though this technology requires more power, a smaller screen has less
power drain.
Brilliant color image – this is a huge
advance in technology, from a Twisted Nematic (TN) display that only
produced 6-bit color, to an 8-bit color display with the IPS technology
Variations to help with user’s viewing
requirements or desires – there are several different forms of IPS
technology: Super-IPS, (S-IPS) Advanced Super IPS, Advanced S-IPS, where
the liquid crystal molecules stay parallel to the front and back panels,
instead of perpendicular when a voltage is applied
Consistent, accurate color, under
different viewing angles
Clear images and stable response time,
which allows for faster response time – good for videos.
TFT display
technologies have developed over the years and have become quite popular in
tech circles. The features offered with this advancing technology are:
Superior color display – for technology
that requires it or for consumers that desire color screens
Not only is the color superb, but the
clarity outstanding
Features a longer half-life, (half-life is
the amount of time in hours before the display is 50% as bright as when it
was first turned on), than OLEDs and comes in varying sizes, from under an
inch up to over 15 inches
Capacitive Touchscreen or touch panel,
which is in the majority of Smartphones and allows for additional
functionality, specifically for zooming and scrolling
Resistive touch panel which is lower in
cost and are usually standard on most TFT devices
Aspect ratio control, which refers to a
screen’s ability to maintain an aspect ratio of a source image at the
hardware level, and 1:1 pixel mapping, used to literally “map” the exact
number of pixels specifically in the source resolution to pixels on the
screen
No “ghosting” (ghosting is when an image
will stay on for a short time when instead it should be off)
Variety of displays, which can be
interfaced through a variety of bus types, including 18 and 24 bit for
red/green/blue, LVDS, and 8 bit and 16 bit for a CPU – many controllers
allow for two or more different types of interfaces on the same TFT screen
History of IPS technology
IPS is the use
of light modulating properties from unlit liquid crystals for providing a flat
panel or electronic visual display. TFT, which stands for Thin Film Transistor,
is an LCD display variant built and marketed for enhanced color, as well as
contrast and black levels. IPS further improves display
technology by providing better color reproduction and a wider, more accurate
viewing angle. IPS TFT LCD technology is widely used for high-performance
computers, laptops, tablets and smartphones. When
Apple brought it to the public’s attention, it took off, and as they say, the
rest is history; but, it really didn’t become widespread or worldwide until
just the late 1990’s. Since then, IPS screens have been implemented in homes
all over the world, with variations to suit one’s electronic needs.
The active matrix IPS TFT LCD was developed by Hitachi in 1996 as a
solution to the display limitations of TN TFT LCDs (Twisted Nematic) from the
late 1980s, which are standard non-IPS LCDs. The TN display is known for its
flawed viewing angles, such as inverting colors at extreme angles, and poor
color quality. By contrast, IPS displays provide wider viewing angles and
higher quality color reproduction by altering pixels to be parallel, rather
than perpendicular. In an IPS screen, the liquid crystals run parallel with the
panels when energized. In a TN display, the crystals turn perpendicular to the
top of the panel. High-performance tablets and smartphones deploy IPS display
technology because these electronics are commonly used to watch movies, video
chat and store photos. The improved angle and color technology features provide
an overall better experience for the user. Creative professionals also benefit
from an IPS monitor because an IPS LCD that provides a wider color gamut and
greater viewing angles help achieve better aesthetic accuracy and superior
results.
Other IPS versions include the following technologies:
Super TFT (IPS) for a
wide viewing angle
Super-IPS (S-IPS) for
color shift free and an improvement on pixel refresh timing
Advanced Super-IPS
(AS-IPS) for high transmittance
Enhanced IPS (E-IPS) for
an enhanced diagonal viewing angle and reductions in response time
Horizontal IPS (H-IPS)
for an improved contrast ratio and an Advanced True White polarizing film
that creates a more natural color of white
Professional IPS (P-IPS)
for truer color depth
History of TFT LCD (Thin-film-transistor
liquid-crystal display) technology
A thin-film-transistor liquid-crystal display (TFT LCD) is a
variant of a liquid-crystal display (LCD) that uses thin-film
transistor (TFT) technology to improve image qualities such as
addressability and contrast. A TFT LCD is
an active-matrix LCD, in contrast to passive-matrix LCDs or
simple, direct-driven LCDs with a few segments.
TFT LCDs are used in appliances including television sets, computer
monitors, mobile phones, handheld video game systems, personal
digital assistants, navigation systems and projectors.
TFT LCDs are also used in car instrument
clusters because they allow the driver to customize the cluster, as well
as being able to provide an analogue-like display
with digital elements.
The relatively inexpensive twisted nematic display is the most
common, consumer, display type.[citation needed] The pixel response time
on modern TN panels
is sufficiently fast to avoid the shadow-trail and ghosting artifacts of
earlier production.[citation needed] The more recent use of RTC (Response
Time Compensation / Overdrive) technologies has allowed manufacturers to
significantly reduce grey-to-grey (G2G) transitions, without significantly
increasing the ISO response time.[citation needed] Response times are now
quoted in G2G figures, with 4ms and 2ms now being commonplace for TN-based
models.[citation needed]
TN displays suffer from limited viewing angles, especially in the vertical
direction. Colors will shift when viewed off-perpendicular. In the vertical
direction, colors will shift so much that they will invert past a certain
angle.
Also, most TN panels represent colors using only six bits per
RGB color, or 18 bit in total, and are unable to display the 16.7 million color
shades (24-bit true color) that are available from graphics cards.
Instead, these panels display interpolated 24-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
Rate Control (FRC), 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 "16.2 million
colors". These color simulation methods are notice able to many people and
highly bothersome to some. FRC tends to be most noticeable in darker
tones, while dithering appears to make the individual pixels of the LCD
visible. Overall, color reproduction and linearity on TN panels is poor. Shortcomings
in display color gamut (often referred to as a percentage of the NTSC 1953
color gamut) are also due to backlighting technology. It is not uncommon for
displays with simple LED or CCFL-based lighting to range from 10% to
26% of the NTSC color gamut, whereas other kind of displays, utilizing more
complicated CCFL or LED phosphor formulations or RGB LED backlights,
may extend past 100% of the NTSC 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, and the sRGB standard
for computer monitors requires a specific nonlinear dependence of the amount of
emitted light as a function of the RGB value.
So, are you ready to delve into
the pros and cons of these two technologies? Granted, we’ve touched on their
features and differences, but now it’s time to ask yourself, which one is
better for me or my business?
We’ve been talking largely about Smartphone
screens, but since both technologies work on smaller screens, such as clocks
and timers or digital thermometers, let’s focus on those.
ADVANTAGES OF IPS DISPLAY
Because of their superior color
and clarity of images, devices using an IPS screens are easy to install on
walls, due to their compact form and low-depth. The Super IPS screens offer a
higher angle of 170˚ for better clarity and wider viewing, particularly at
night. Images remain stable and clear and not sparkly, shiny, like other screens;
they also have a longer battery life and screen life, (on smaller screens of
course) because of the lower electrical output. The release of heat is lower,
again because of the reduced electrical consumption. The colors are also more
vibrant and clear, not pixelated like other lower quality-type devices. As
mentioned earlier, there are also many variations of IPS technology to suit
your needs and desires.
DISADVANTAGES OF IPS DISPLAY
Now we will go over the downside
of IPS screens, which we briefly touched on above, which includes a major
disadvantage: cost. If you’re just looking for an average Smartphone or don’t
need all the fancy coloring and clarity for LCD displays, then cost may not be
a big factor; however, this is the main reason why IPS technology is beginning
to come down. As with every new invention, discovery or technology, demand is
everything. Another disadvantage is that colors may not always transcribe
correctly or accurately, which may or may not be a deterrent. Also, high
resolutions are not always readily available for personal applications. In
certain circumstances, the brightness may not be enough, especially in
darkness.
ADVANTAGES OF TFT DISPLAY
With TFT display technologies,
less energy consumption is a big deal, especially when dealing with bigger
screens, and of course less electricity means lower cost, overall. The
visibility is sharper, meaning no geometric distortion, which is great for these
tired, old eyes. The response time and physical design of the screens are also
appealing. TFT displays can also save space and be placed virtually anywhere in
an office or home, because of the brightly lit feature and crisp clear images.
DISADVANTAGES OF TFT DISPLAY
Some cons of TFT screens deal
with the viewing angle, which create distortion, resulting in a
less-than-perfect image. Static resolution, meaning the resolution can’t be
changed, may also cause a problem, but newer models seem to have tackled that
issue. The accuracy of the display of colors is not perfect, specifically
strong blacks and bright whites, so when printing an image, it may not display
the spectrum of colors.
And there you have it. In the
future, even this superb technology will change and new, more exciting
technology will take its place. But until then, IPS & TFT screens are
forging ahead with their own advances and improvements, so stayed tune. You
don’t want to miss it.
Maclight display(www.szmaclight.com) is focus in lcd display, IPS TFT and tn tft lcd are our main productons, welcome to contact us at: [email protected]
