tft lcd screen vs super amoled free sample

AMOLED and TFT are two types of display technology used in smartphones. AMOLED (active-matrix organic light-emitting diode) displays are made up of tiny organic light-emitting diodes, while TFT (Thin-Film Transistor) displays use inorganic thin-film transistors.

AMOLEDs are made from organic materials that emit light when an electric current is passed through them, while TFTs use a matrix of tiny transistors to control the flow of electricity to the display.

Refresh Rate: Another key difference between AMOLED and TFT displays is the refresh rate. The refresh rate is how often the image on the screen is updated. AMOLED screens have a higher refresh rate than TFT screens, which means that they can display images more quickly and smoothly.

Response Time: The response time is how long it takes for the pixels to change from one colour to another. AMOLED screens have a shorter response time than TFT screens..

Colour Accuracy/Display Quality: AMOLED screens are more accurate when it comes to displaying colours. This is because each pixel on an AMOLED screen emits its own light, which means that the colours are more pure and true to life. TFT screens, on the other hand, use a backlight to illuminate the pixels, which can cause the colours to appear washed out or less vibrant.

Viewing Angle: The viewing angle is the angle at which you can see the screen. AMOLED screens have a wider viewing angle than TFT screens, which means that you can see the screen from more angles without the colours looking distorted.

Power Consumption: One of the main advantages of AMOLED displays is that they consume less power than TFT displays. This is because the pixels on an AMOLED screen only light up when they need to, while the pixels on a TFT screen are always illuminated by the backlight.

Production Cost: AMOLED screens are more expensive to produce than TFT screens. This is because the manufacturing process for AMOLED screens is more complex, and the materials used are more expensive.

Availability: TFT screens are more widely available than AMOLED screens and have been around for longer. They are typically used in a variety of devices, ranging from phones to TVs.

Usage: AMOLED screens are typically used in devices where power consumption is a concern, such as phones and wearable devices. TFT screens are more commonly used in devices where image quality is a higher priority, such as TVs and monitors.

AMOLED and TFT are two different types of display technology. AMOLED displays are typically brighter and more vibrant, but they are more expensive to produce. TFT displays are cheaper to produce, but they are not as bright or power efficient as AMOLED displays.

The display technology that is best for you will depend on your needs and preferences. If you need a screen that is bright and vibrant, then an AMOLED display is a good choice. If you need a screen that is cheaper to produce, then a TFT display is a good choice. However, if you’re worried about image retention, then TFT may be a better option.

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Thanks for the display technology development, we have a lot of display choices for our smartphones, media players, TVs, laptops, tablets, digital cameras, and other such gadgets. The most display technologies we hear are LCD, TFT, OLED, LED, QLED, QNED, MicroLED, Mini LED etc. The following, we will focus on two of the most popular display technologies in the market: TFT Displays and Super AMOLED Displays.

TFT means Thin-Film Transistor. TFT is the variant of Liquid Crystal Displays (LCDs). There are several types of TFT displays: TN (Twisted Nematic) based TFT display, IPS (In-Plane Switching) displays. As the former can’t compete with Super AMOLED in display quality, we will mainly focus on using IPS TFT displays.

OLED means Organic Light-Emitting Diode. There are also several types of OLED, PMOLED (Passive Matrix Organic Light-Emitting Diode) and AMOLED (Active Matrix Organic Light-Emitting Diode). It is the same reason that PMOLED can’t compete with IPS TFT displays. We pick the best in OLED displays: Super AMOLED to compete with the LCD best: IPS TFT Display.

Super AMOLED (S-AMOLED) and Super LCD (IPS-LCD) are two display types used in different kinds of electronics. The former is an improvement on OLED, while Super LCD is an advanced form of LCD.

All things considered, Super AMOLED is probably the better choice over Super LCD, assuming you have a choice, but it"s not quite as simple as that in every situation. Keep reading for more on how these display technologies differ and how to decide which is best for you.

S-AMOLED, a shortened version of Super AMOLED, stands for super active-matrix organic light-emitting diode. It"s a display type that uses organic materials to produce light for each pixel.

One component of Super AMOLED displays is that the layer that detects touch is embedded directly into the screen instead of existing as an entirely separate layer. This is what makes S-AMOLED different from AMOLED.

Super LCD is the same as IPS LCD, which stands forin-plane switching liquid crystal display. It"s the name given to an LCD screen that utilizes in-plane switching (IPS) panels. LCD screens use a backlight to produce light for all the pixels, and each pixel shutter can be turned off to affect its brightness.

There isn"t an easy answer as to which display is better when comparing Super AMOLED and IPS LCD. The two are similar in some ways but different in others, and it often comes down to opinion as to how one performs over the other in real-world scenarios.

For example, one quick consideration is that you should choose S-AMOLED if you prefer deeper blacks and brighter colors because those areas are what makes AMOLED screens stand out. However, you might instead opt for Super LCD if you want sharper images and like to use your device outdoors.

S-AMOLED displays are much better at revealing dark black because each pixel that needs to be black can be true black since the light can be shut off for each pixel. This isn"t true with Super LCD screens since the backlight is still on even if some pixels need to be black, and this can affect the darkness of those areas of the screen.

What"s more is that since blacks can be truly black on Super AMOLED screens, the other colors are much more vibrant. When the pixels can be turned off completely to create black, the contrast ratio goes through the roof with AMOLED displays, since that ratio is the brightest whites the screen can produce against its darkest blacks.

However, since LCD screens have backlights, it sometimes appears as though the pixels are closer together, producing an overall sharper and more natural effect. AMOLED screens, when compared to LCD, might look over-saturated or unrealistic, and the whites might appear slightly yellow.

When using the screen outdoors in bright light, Super LCD is sometimes said to be easier to use, but S-AMOLED screens have fewer layers of glass and so reflect less light, so there isn"t really a clear-cut answer to how they compare in direct light.

Another consideration when comparing the color quality of a Super LCD screen with a Super AMOLED screen is that the AMOLED display slowly loses its vibrant color and saturation as the organic compounds break down, although this usually takes a very long time and even then might not be noticeable.

Without backlight hardware, and with the added bonus of only one screen carrying the touch and display components, the overall size of an S-AMOLED screen tends to be smaller than that of an IPS LCD screen.

This is one advantage that S-AMOLED displays have when it comes to smartphones in particular, since this technology can make them thinner than those that use IPS LCD.

Since IPS-LCD displays have a backlight that requires more power than a traditional LCD screen, devices that utilize those screens need more power than those that use S-AMOLED, which doesn"t need a backlight.

That said, since each pixel of a Super AMOLED display can be fine-tuned for each color requirement, power consumption can, in some situations, be higher than with Super LCD.

For example, playing a video with lots of black areas on an S-AMOLED display will save power compared to an IPS LCD screen since the pixels can be effectively shut off and then no light needs to be produced. On the other hand, displaying lots of color all day would most likely affect the Super AMOLED battery more than it would the device using the Super LCD screen.

An IPS LCD screen includes a backlight while S-AMOLED screens don"t, but they also have an additional layer that supports touch, whereas Super AMOLED displays have that built right into the screen.

For these reasons and others (like color quality and battery performance), it"s probably safe to say that S-AMOLED screens are more expensive to build, and so devices that use them are also more expensive than their LCD counterparts.

These days you really only have two choices of screens when you are buying a smartphone or tablet: LCD or AMOLED. Many of you probably can’t tell the difference between the two screen types, but both technologies have inherent strengths and weaknesses. LCD has been around for a while, but AMOLED phones are gaining popularity thanks to Samsung and other manufacturers. There isn’t a clear winner at this point in time, so here’s a look at both.

LCD, Liquid Crystal Display, has been a part of our lives for years now. Besides mobile devices, we see LCD screens being used with almost every computer monitor, and in the majority of TVs. While these screens are made of wondrous liquid crystals, they also require a couple panes of glass, and a light source. LCD screens produce some of the most realistic colors you can find on a screen, but might not offer as wide of a contrast ratio (darker darks and brighter brights) as an AMOLED screen.

Some common terms you will find associated with LCD displays are TFT and IPS. TFT stands for Thin Film Transistor, which makes the wiring of LCD screens more efficient by reducing the number of electrodes per pixel. One benefit of TFT displays is an improved image quality over standard LCD screens. Another popular LCD technology is In-Plane Switching, or IPS, which improves upon TFT by offering much wider viewing angles and color reproduction on LCD screens. IPS screens are able to achieve this by keeping all the liquid crystals parallel to the screen. IPS is generally preferable to standard TFT.

AMOLED, Active Matrix Organic Light Emitting Diode, technology has grown in popularity in recent years, particularly among Samsung products. AMOLED screens consist of a thin layer of organic polymers that light up when zapped with an electric current. Due to this simple construction, AMOLED screens can be extremely thin and do not require a backlight. The benefit of losing a backlight is readily apparent: these screens are able to produce blacks so deep that the screen pixels can shut right off. Shutting off pixels can also save electricity and battery life in phones and tablets. Just keep your backgrounds close to black and you’ll save energy.

Sometimes when you read about AMOLED screens, you might hear people complaining about something called a “pentile” display. This is a feature of most color AMOLED screens. Instead of having just a single red, blue, and green sub pixel per actual pixel, pentile displays have a RGBG sub pixel layout which has two green sub pixels for each red and blue. The positive of this technology is that you are able to create a screen that is just as bright as normal screens with one third the amount of sub pixels. The negative of pentile screens is that they can appear grainy, or appear to be lower resolution due to the larger, more visible sub pixels. For a while, Samsung begun using a display type called Super AMOLED Plus, which does not use a pentile sub pixel layout and also improves viewability in direct sunlight — traditionally a weakness for AMOLED. Samsung equipped the Galaxy S II with a Super AMOLED plus screen, but then reverted back to Super AMOLED screens for the Galaxy S III, citing screen life as the reason for the switch.

There are pros and cons for each type of screen, and both screen technologies can produce vivid, beautiful displays. The only way to know for sure if the screen on your future device will satisfy you is to try it out for yourself. You will be able to easily see if the screen viewing angles, contrast ratio, and color reproduction will fit your needs after using the phone for just a few minutes.

Roughly speaking there are two main types of displays used in smartphones: LCD and LED. These two base technologies have been refined and tweaked to give us AMOLED and IPS LCD. The former stands for Active Matrix Organic Light-Emitting Diode, while the latter means In-Plane Switching Liquid Crystal Display.

All of this hasn’t gone unnoticed by the marketing people, which means that plain old AMOLED or regular IPS LCD aren’t the terms used in the marketing fluff. Instead, we have Super AMOLED, Dynamic AMOLED, Super LCD, Super Retina OLED, Super Retina XDR, Infinity Display, and so on. But what’s any of that actually mean?

The LED part of AMOLED stands for Light Emitting Diode. It’s the same tech as you find on many home appliances that show that the power is on with a little red light. An LED display takes this concept, shrinks it down, and arranges the LEDs in red, green, and blue clusters to create an individual pixel.

The O in AMOLED stands for organic. It refers to a series of thin organic material films placed between two conductors in each LED. These produce light when a current is applied.

Finally, the AM part in AMOLED stands for Active Matrix, rather than a passive matrix technology. In a passive matrix, a complex grid system is used to control individual pixels, where integrated circuits control a charge sent down each column or row. But this is rather slow and can be imprecise. Active Matrix systems attach a thin film transistor (TFT) and capacitor to each sub-pixel (i.e. red, green, or blue) LED. The upshot is that when a row and column is activated, the capacitor at the pixel can retain its charge in between refresh cycles, allowing for faster and more precise control.

The image above is a close-up shot of the AMOLED display on the Samsung Galaxy S8. The RGB triangular pattern is clearly shown. Towards the bottom of the image, the green and red LEDs are off and the blue LEDs are on only slightly. This is why AMOLED displays have deep blacks and good contrast.

Super AMOLED is a marketing term from Samsung. It means a display that incorporates the capacitive touchscreen right in the display, instead of it being a separate layer on top of the display. This makes the display thinner.

Dynamic AMOLED is another marketing term from Samsung. It denotes Samsung’s next-generation AMOLED display which includes HDR10+ certification. According to Samsung, Dynamic AMOLED also reduces the harmful blue light emitted from the display, which helps reduce eye strain and helps lessen sleep disturbances if you’re using your phone late in the day!

As for Infinity Display (or Infinity-O Display), it is more marketing from Samsung. It means “a near bezel-less, full-frontal, edge-to-edge” display. However, it is still a Super AMOLED unit.

LCD displays work with a backlight that shines through some polarizing filters, a crystal matrix, and some color filters. Liquid crystals untwist when an electric charge is applied to them, which affects the frequency of the light that can pass through. Since the crystals can be twisted to varying degrees depending on the voltage used, a display can be built when they are used with polarized panels. A grid of integrated circuits is then used to control each pixel, by sending a charge down into a specific row or column. Colors are created by the use of red, green, and blue filters, known as sub-pixels, which are then blended by varying degrees to produce different colors.

The above image is of an LCD display from a Huawei Mate 8. Notice how the pixels are made up of equally-sized sub-pixels, one for each of the colors: red, green, and blue.

Like Super AMOLED, a Super LCD display also incorporates the touchscreen. There is no “air gap” between the outer glass and the display element, which means it has similar benefits to Super AMOLED.

Samsung isn’t the only company that is good at marketing, there is another! Apple has coined the term “Retina” for its displays. The term was first used for its smartphones with the launch of the iPhone 4, as it offered a significantly greater pixel density (over 300 ppi) when compared to the iPhone 3GS. Later came Retina HD, which applies to iPhones with at least a 720p screen resolution.

All Retina and Retina HD displays on the iPhone are LCD IPS displays. However, things have changed a bit with the iPhone X as it features an AMOLED display, now marketed under the term Super Retina. It’s still an AMOLED display. It just has extra adjectives. With the launch of the iPhone 11 Pro, Apple coined the term Super Retina XDR. The XDR part means Extended Dynamic Range, as they have better contrast ratios and higher peak brightness.

Not all Retina displays use OLED. Although the MacBook Pro is marketed with a “Retina” display, as you can see from the magnified image above, it is a regular LCD, even if it uses the latest Apple silicon.

Both technologies can be used to build displays with 720p, 1080p, Quad HD, and 4K resolutions. And OEMs have made handsets that support HDR10 using both LCD and AMOLED displays. So from that point of view, there isn’t much difference between the two.

When it comes to color, we know that the blacks will be deeper and the contrast ratios higher on AMOLED displays. But, overall color accuracy can be high on both types of display.

One of the main weaknesses of AMOLED displays is the possibility of “burn-in”. This is the name given to a problem where a display suffers from permanent discoloration across parts of the panel. This may take the form of a text or image outline, fading of colors, or other noticeable patches or patterns on the display. The display still works as normal, but there’s a noticeable ghost image or discoloration that persists. It occurs as a result of the different life spans between the red, green, and blue LED sub-pixels used in OLED panels.

The theoretical lifespan of an AMOLED display is several years, even when used for 12 hours a day. However, there is anecdotal evidence that some displays suffer from burn-in quicker than others. Displays that show signs of burn-in after only a few months should be considered defective because they certainly aren’t normal.

While owners of devices with LCD screens might congratulate themselves for picking a smartphone that is immune to burn-in, there can be a problem with LCD panels called “image retention.” Put simply, liquid crystals can develop a tendency to stay in one position when left at the same voltage for extended periods. Thankfully this phenomenon is normally temporary and can usually be reversed by allowing the liquid crystals to return to their relaxed state.

Picking a winner can be hard as there are many factors to consider, not only about the display technologies but also about the other components in a handset. For example, if you are an AMOLED fan, then would you consider a device with large storage and a good processor, but with an LCD display? The same argument works the other way for LCD fans. Generally, you’ll be fine with either display type, so just pick the handset you like.

Higher-end devices typically sport AMOLED displays and mid-range/budget devices usually use LCD. But that isn’t set in concrete as there are plenty of high-end devices that have LCD displays. With OLED production costs dropping dramatically in recent years, more and more budget options will be offering OLED panels in the future.

Companies like LG and Samsung have seen this trend coming and are rapidly expanding their OLED (and flexible OLED) production capabilities. LCD might still have a bright future in televisions and other large-panel applications, but for now, it looks like mobile will be increasingly dominated by OLED screens.

What do you think? AMOLED or LCD? What about the terms like Retina vs Infinity Display? Are they meaningful to you? Please let me know in the comments below.

One of such trade-offs that buyers often have to bear is choosing between a higher refresh rate or an AMOLED panel. But which is more important for a better experience: a fast 120Hz LCD panel or a 60Hz AMOLED one? Let"s find out.

How fast a screen can refresh affects how well it can simulate motion. In other words, it makes animations appear more natural and fluid as opposed to laggy and jittery. Earlier, the standard refresh rate for smartphones used to be 60Hz. But ever since OnePlus popularized high refresh rate displays, they have become common in the tech industry.

Unlike a regular LCD, an AMOLED display provides more vivid image quality, consumes less power, and does a better job at reducing screen glare. This means that any content you consume on your phone—from games to movies to social media—will appear brighter and more colorful, all while saving your battery life.

Each pixel produces its own light on an AMOLED panel, unlike LCD or IPS panels that use a backlight to illuminate the screen. Because of this, the former can show darker colors and deep blacks more accurately since it can just turn a pixel off to represent an absence of light. On the latter, the same colors appear washed out or faded.

When using Dark Mode (or Night Mode) on an AMOLED panel, the workload of the display is reduced since a measurable portion of the screen is basically turned off. Only the pixels that show colors need to be illuminated, whereas the black pixels can remain shut off. As a result, you save battery life while viewing dark content on an AMOLED screen.

If you"re a gamer, a high refresh rate display will serve you better than an AMOLED one, making your gaming experience much smoother. However, note that the higher the refresh rate, the faster you will drain your battery. Also, keep in mind that many mobile games only support 60Hz, so the benefit of having a 90Hz or 120Hz screen may be redundant.

​​​​On the flip side, if you"re someone who consumes a lot of video content like movies, TV shows, YouTube videos, or TikTok clips, then having an AMOLED panel is clearly the better choice since it will improve the color accuracy and vividness dramatically.

As premium features become more common, they"re quickly making their way into budget phones. Having a high refresh rate AMOLED display is obviously better if you can find such a device in the budget category. But if you can"t, you have to trade one for the other.

Since budget phones come with weaker chips, the games you play may not always take advantage of that high refresh rate screen, making them a bit unnecessary apart from smoother scrolling of social media feeds. However, an AMOLED panel will continue to enrich your viewing experience no matter what.

Advancements in technology have led to better, brighter display systems, redefining our experience of viewing content. Better picture quality and crystal-clear images are some of the benefits of new displays such as AMOLED and IPS LCD

When choosing which television or mobile phone to buy, it’s essential to consider the display quality and technology. Here are the differences between Super AMOLED and IPS LCD screens, two of the forerunners in display technology, and an analysis of which one of the two is better.

LCD, short for liquid crystal display, has a flat panel display. It is an electronically controlled optical device that uses the liquid crystals" light-modified properties along with polarisers. The liquid crystals do not directly emit light. Hence, a reflector and a backlight generate images either in monochrome or colour. An LCD blocks the light instead of emitting it and is used more widely in televisions and basic smartphones. IPS, which stands for in-plane switching, is a screen technology for LCD.

AMOLED is short for Active Matrix Organic Light-Emitting Diodes. This type of OLED is usually incorporated in flagship smartphones and modern televisions. It uses the latest technology of a particular type of thin display. The organic compounds present in it produce electroluminescent material.

The active matrix comes from the technology that addresses the pixels effectively. Super AMOLED contains integrated touch functionality. It exhibits a variety of colours and has exceptional clarity, translating into superior resolution.

AMOLED has a thinner film transistor fixed to every LED alongside a capacitor. AMOLED and IPS LCD screens are made using three pixels—red, blue, and green. LCDs generate light through a backlight. With AMOLED displays, every pixel has a separate light source, eliminating the need for a backlight. As a result, the display assembly is thinner and provides consistent lighting throughout the complete screen.

Each of these displays has its specialities. Nevertheless, if we compare Super AMOLED display vs IPS LCD, the former is better because it integrates the latest technologies and has excellent performance.

Some tablets and smartphones ship with an AMOLED display. Newer ones are shipping with a "Super AMOLED" display. What so super about it, and what does all this alphabet soup even mean?

The short version is that a Super AMOLED touchscreen display integrates touch sensors with the glass surface panel, eliminating at least one layer of glass and with it, a layer of air. That"s what makes Super AMOLED super. Only Samsung makes it.

I said "at least one layer of glass" because AMOLED itself eliminates at least one layer in a display. The current Galaxy Tab, for example, uses a TFT-LCD (Thin-Film Transistor Liquid Crystal Display) screen. Until very recently, TFT-LCD has been the state of the art in thin color displays and is still the only cost-effective option in the vast majority of displays larger than a smartphone screen.

TFT-LCD has approximately four layers: a backlight, a TFT color filter, a touch-sensor panel, and an outer glass screen. AMOLED (Active-Matrix Organic Light-Emitting Diode) eliminates the separate backlight. AMOLED, however, is known for having problems with glare and readability in direct sunlight, even relative to average LCD screens. By minimizing the number of reflective surfaces and power necessary to achieve vivid color, Super AMOLED was designed in part to address this.

Samsung introduced Super AMOLED to commercial devices this year with the Samsung Wave, which ran their own Bada OS. The Android-powered Samsung Galaxy series of smartphones made the displays popular, and it"s since appeared on Samsung"s Windows Phone 7 handsets as well.

There are other advanced color technologies in the market, all of them super, and all of them extra-expensive: Super LCD recently joined Super IPS and Advanced Super View. But only Super AMOLED has really captured the popular imagination.

A 7-inch Android tablet with an AMOLED display would probably be a serious advance over its current LCD screen. But if it"s "just" AMOLED, something about it would just seem ... less than super.

In this edition of Primed, we"ll be examining the different qualities and underlying technologies of several displays, starting with the ubiquitous TFT-LCD and moving through the nascent realm of glasses-free 3D and beyond. We"ll also be addressing the importance of resolution and pixel density. Finally, we"ll be scoping out a handful of upcoming technologies -- while some are thoroughly intriguing, others are just plain wacky. Go ahead... buy the ticket, take the ride, and join us after the break. It"s Primed time.

Generally speaking, two display types rule today"s mobile phones: the Liquid Crystal Display (LCD), and the Organic Light-Emitting Diode (OLED). While each technology carries a set of strengths and weaknesses, a very important distinction can be drawn between the two. The LCD uses the light modulating properties of liquid crystals (LCs), but LCs don"t emit light directly. As such, a light source is necessary for proper viewing. Conversely, the OLED uses organic compounds that illuminate when exposed to electric currents. As backlights aren"t necessary for OLEDs, they"re significantly thinner than traditional LCDs. All things equal, OLED phones should be slimmer than their LCD counterparts, but this isn"t always the case. Take for example the MEDIAS N-04C, which uses a TFT-LCD and measures 7.7mm thin, versus the Galaxy S II, which uses the latest Super AMOLED Plus display and is 8.5mm thick.

The most desirable phone displays today are variants of these two technologies. In the LCD camp, there"s the Super LCD (S-LCD) and the IPS display -- with the latter as the basis for the Retina Display and the NOVA display. Likewise, the OLED territory is filled with options such as Super AMOLED, Super AMOLED Plus and ClearBlack. We"ll discuss the important distinctions between these competing display types shortly, but first let"s develop a fundamental understanding of how these brilliant creations work and how they came to be.

The story of the LCD began in 1888 when cholesterol was extracted from carrots. Think we reached too far back? Not if you"ve ever wondered what liquid crystals are. You see, a botanist named Friedrich Reinitzer discovered this extract had two distinct boiling points and observed the molecule"s ability to transmute from liquid to a crystalline structure in the interim. Even more shocking, the cloudy substance was able to reflect circularly polarized light and rotate the light"s polarization. (This little tidbit will become important when we discuss how LCDs operate.) While liquid crystals appear throughout nature, it wasn"t until 1972 -- when 5CB (4-Cyano-4"-pentylbiphenyl) was synthesized -- that they became commercially viable. A first of its kind, 5CB was chemically stable and entered its nematic phase at room temperature. While there"s actually three phases of liquid crystals, we"re most interested in the nematic one. This describes a state where molecules flow like liquid and self-align in a thread-like helix -- and coincidentally, are easily manipulated with electricity.

Now that you"ve got a little background about liquid crystals, let"s examine how they"re used in LCDs. Let"s start by making a sandwich. As our bread, we"ll take two polarizing filters, one which polarizes light on the horizontal axis and the other on the vertical axis. If we take the slices of bread and hold them up to a light source, nothing is going to pass through. Remember when we said liquid crystals have the ability to rotate light"s polarization? Yeah, they"re a critical ingredient in our sandwich because they determine light"s passage. When nematic crystals are in their natural (or relaxed) state, they form a twisted helix. As light travels through the molecule structure, its polarization is rotated by 90 degrees and light is allowed to pass through the top filter. Conversely, when voltage is applied to the LCs, the helix is broken and light can"t escape the polarizing filters. If you"re keeping score, this is known as the twisted nematic field effect. Going back to the sandwich analogy, the nematic crystals are placed between two layers of transparent electrodes which apply voltage to the liquid crystals. It"s a rather simplistic sandwich, but it describes the fundamentals of how LCDs work. For you visual learners, Bill Hammack does an excellent job of explaining these concepts in the following video.

Now let"s apply this knowledge to the modern TFT-LCD that you"re familiar with. It"s the basis for twisted nematic (TN) and in-plane switching (IPS) displays, and both technologies rely upon the thin film transistor (TFT) for the quick response time and image clarity that we take for granted. Fundamentally, the TFT is a matrix of capacitors and transistors that address the display pixel by pixel -- although at a blistering speed. Every pixel consists of three sub-pixels -- red, green and blue -- each with its own transistor, and a layer of insulated liquid crystals are sandwiched between conductive indium tin oxide layers. Shades are made possible by delivering a partial charge to the underlying LCs, which controls the amount of light that passes through the polarizing filter, thus regulating the intensity of each sub-pixel.

The most common LCD display is based on TN technology, which has been successful due to its relatively inexpensive production costs and fast refresh rates. Many of you will remember the shadow-trail that plagued early LCDs, and faster refresh rates reduce this effect and make the displays better suited for movies and games. Unfortunately, TN displays are famous for exhibiting poor viewing angles and most aren"t capable of showing the entire 24-bit sRGB color gamut. In attempt to mimic the full range of 16.7 million colors, many screens implement a form of dithering to simulate the proper shade. Basic TN screens are hardly fantastic, but they"re also good enough to survive the day without eliciting too many complaints.

Another technology that"s gotten plenty of airtime is the Super LCD (S-LCD), which is a display that"s manufactured by a joint-venture between Sony and Samsung. It employs an alternate method to IPS and TN that"s known as super patterned vertical alignment (S-PVA). Here, the liquid crystals have varying orientations, which help colors remain uniform when viewed from greater angles. S-LCDs also feature improved contrast ratios over traditional TN displays, which exposes a greater amount of details in dark images. Further, these displays feature dual sub-pixels that selectively illuminate based on the brightness of the screen. As you can imagine, this provides power-saving benefits, along with refined control of colors on the screen.

Now, let"s take a look at OLEDs, which are a staple of many high-end phones today. As we"ve mentioned, these displays operate without a backlight. Instead, they use electroluminescent organic compounds that emit light when they"re exposed to an electric current. The main advantages of OLEDs include deeper black levels (because there"s no backlight), enhanced contrast ratios, and excellent viewing angles, while drawbacks include reduced brightness and colors that are often over-saturated. OLED screens also suffer an awkward aging effect, where the red, green and blue sub-pixels will deteriorate and lose efficiency at different rates, which causes brightness and color consistency to worsen over time. While improvements are being made, it"s important to understand that this display technology is still relatively immature.

You"re most likely familiar with the active-matrix OLED (AMOLED), which relies on a TFT backplane to switch individual pixels on and off. Coincidentally, active-matrix displays consume significantly less power than their passive-matrix OLED (PMOLED) counterparts, which makes them particularly well-suited for mobile devices. These displays are typically manufactured by printing electroluminescent materials onto a substrate, and that relatively simplistic process suggests that OLEDs will ultimately become cheaper and easier to manufacture than LCDs. Shockingly, the most challenging step is the creation of the substrate itself, which remains a difficult and expensive endeavor. Currently, the limited supply and high demand of AMOLED screens has restricted their availability, and you"re most likely to find them in high-end smartphones.

While all screens suffer from reduced visibility in direct sunlight, the original AMOLED screens were particularly vulnerable to this drawback. To resolve this, Samsung introduced the Super AMOLED display. With this new technology, the touch sensors were integrated into the screen itself. Naturally, this allowed for a thinner display, but this also improved brightness by eliminating the extra layer. Additionally, the screen"s reflection of ambient light and power consumption were significantly reduced. While colors were now bright and vibrant -- and acceptable in direct sunlight -- the displays still couldn"t match the crispness and clarity of LCD screens, particularly with respect to text. Samsung"s PenTile matrix is to blame, which is a hallmark of its AMOLED and Super AMOLED displays. Here, a single pixel is composed of two sub-pixels, either red and green, or blue and green, and the green sub-pixel is significantly more narrow than the other two. While the scheme works fine for images because the human eye is more sensitive to green, it makes the anti-aliasing of text rather imprecise, and the end result is a bit blurry. Like Super AMOLED, Nokia"s ClearBlack display was created to make the AMOLED screen more visible in direct sunlight. This was accomplished by adding a polarized filter to the display, which allows the viewer to see through the screen"s reflection and view the images as they would appear under more ideal conditions.

In its most recent incarnation, the Super AMOLED Plus features a traditional three sub-pixels of equal proportion within one pixel, along with an increased sub-pixel count and density. Both of these measures create a display that"s much more crisp, especially when it comes to text. Further, the tighter spacing between pixels results in better visibility under direct sunlight. The new Super AMOLED Plus screens are also thinner and brighter to boot.

By now, you"ve probably had the chance of viewing a glasses-free 3D screen for yourself. Whether you think the feature is cool, gimmicky or annoying -- or, all of the above -- it"s clear that autostereoscopic displays are moving into the mainstream. If you"ve ever wondered what makes this marvel possible, today is your lucky day. First, let"s start with stereoscopic imaging itself. This merely refers to a technique that creates an illusion of depth by presenting two offset images separately to the right and left eye of the viewer. Traditionally, glasses were required to complete the effect, but a creation known as the parallax barrier has done away with that. Essentially, it"s a layer of material placed atop the screen with precision slits that allows each eye to view a different set of pixels. As you"ve likely observed (or at least read about), you"re required to position the display at a very specific angle to properly view the 3D effect. Also, because the parallax barrier effectively blocks half the light emanating from the screen, the backlight is forced to shine twice as bright -- which really kills the battery. Granted, it"s an infant as technology goes, but researchers are already making refinements. For example, MIT"s HR3D is a promising project that touts better viewing angles, brightness and battery life -- largely by increasing the number and varying the orientation of the slits.

So far, we"ve discussed the underlying technologies of mobile displays, but these options are merely one factor for consideration as you select your next phone. Screen resolution is another very important topic, as it determines the amount of content that can be displayed at any given time. Many of you are likely aware of this, but the physical size of a screen conveys nothing about the content that it can display. For example, a 4.5-inch screen with an 800 x 480 resolution actually displays less information than a 3.5-inch screen with a 960 x 640 resolution. These numbers are simply measures of the physical number of pixels positioned vertically and horizontally across the screen. Taking it a step further, the 800 x 480 screen is capable of displaying 384,000 pixels worth of information, while the 960 x 640 screen is capable of displaying 614,400 pixels worth of information. Put simply, a low-res screen simply can"t convey the same amount of content as a high-res alternative.

The most common displays today are generally based around the Wide VGA (WVGA, 800 x 480) standard, and lower-res options include Half VGA (HVGA, 480 x 320) and Quarter VGA (QVGA, 320 x 240). Another variation of this is Full Wide VGA (FWVGA, 854 x 480), which is common to Motorola"s Droid family. Quarter HD (qHD) is an up-and-comer in the mobile industry, with a 960 x 540 resolution, which is one quarter the pixel count of full 1080 HD (1920 x 1080). Lest we not forget Apple"s Retina Display, which measures 960 x 640. As you"ve seen in our reviews, we"re particularly fond of high-res screens, and HVGA really is the minimum that you should accept when purchasing a new phone.

Another component of screen resolution is pixel density, which is the total number of pixels within a physical constraint. It"s calculated in pixels per inch (ppi), which is fundamentally a measure of how tightly pixels are squeezed together. This element was somewhat of an afterthought until Apple introduced the Retina Display, but it has important ramifications for the overall crispness of text and images. While the iPhone 3GS came with a 3.5-inch screen with an HVGA resolution, the iPhone 4 kept this same screen size yet boosted its resolution to 960 x 640. The result was a massive increase in pixel density, which grew from 163ppi in the iPhone 3GS to a staggering 326ppi with the iPhone 4. Of course, these numbers are merely academic until you examine the impact that a high pixel density has upon the overall legibility of small text and clarity of images. As you"d expect, other manufacturers aren"t letting Apple have all the fun in the pixel density war, and we"re seeing particularly exciting developments from Toshiba and Samsung (more on that a bit later).

If you"re interested in calculating pixel density for yourself, you"ll need to start by knowing the display size and screen resolution. From there, you"ll need to determine the diagonal resolution of the screen with a little help from our friend Pythagoras (famous for the Pythagorean theorem). For our purposes, his equation is best expressed as follows:

Now that we"ve examined display technologies and screen resolution, let"s take a brief moment to discuss touch screens, which are crucial elements for modern smartphones. The dominant touchscreen technology is known as capacitive touch, which receives feedback from your body"s ability to conduct electricity. When you place a finger on the display, the screen"s electrostatic field becomes distorted, and the change in capacitance is registered by the underlying sensor. From there, software is used to react to your input. The beautiful part about a capacitive touchscreen is its ability to register multiple points of contact at the same time, which enables multi-touch functionality such as pinch-to-zoom.

Another type of touchscreen on the market today is known as the resistive touchscreen. It"s generally less expensive to produce and responds to physical force. While there are multiple elements to a resistive screen, the most important are two electrically conductive layers that are separated by a narrow space. When you press on the display, the two layers come into contact with one another, which registers as a change in current. Unfortunately, these added layers reduce the overall brightness of the display and increase the amount of glare reflected from the screen. You"ll generally find resistive touch screens in lower-end smartphones because they don"t support multi-touch, although a few individuals appreciate its ability to receive input from a stylus, gloved fingers or fingernails.

Ortustech (a joint-venture between Casio Computer and Toppan Printing) has developed a 4.8-inch screen with full 1080p resolution and a stunning pixel density of 458ppi. While a touchscreen isn"t in the mix, manufacturers understand the appeal of full HD, and we"re seeing the industry continually advancing upon this holy grail. Likewise, Hitachi has announced a 4.5-inch IPS display with a 1280 x 720 resolution that supports glasses-free 3D to boot. Toshiba has introduced a 4-inch contender, also at 720p, with a stunning 367ppi resolution. Samsung isn"t resting on its laurels, either, and is working on mobile displays that will push between 300 and 400ppi -- by 2015, anyway. While this announcement was specifically for tablets, we know Sammy"s smartphones are bound to benefit.

If you find your current smartphone far too rigid, 2012 could be quite a milestone, as Samsung is readying flexible AMOLED displays for production next year. While we plan to see smartphones with large screens that can be folded into a smaller form -- a definite improvement over current hinge-based designs -- we"d love to see an outlandish solution that fully incorporates the flexible spirit.

A thin-film-transistor liquid-crystal display (TFT LCD) is a variant of a liquid-crystal display that uses thin-film-transistor technologyactive matrix LCD, in contrast to passive matrix LCDs or simple, direct-driven (i.e. with segments directly connected to electronics outside the LCD) LCDs with a few segments.

In February 1957, John Wallmark of RCA filed a patent for a thin film MOSFET. Paul K. Weimer, also of RCA implemented Wallmark"s ideas and developed the thin-film transistor (TFT) in 1962, a type of MOSFET distinct from the standard bulk MOSFET. It was made with thin films of cadmium selenide and cadmium sulfide. The idea of a TFT-based liquid-crystal display (LCD) was conceived by Bernard Lechner of RCA Laboratories in 1968. In 1971, Lechner, F. J. Marlowe, E. O. Nester and J. Tults demonstrated a 2-by-18 matrix display driven by a hybrid circuit using the dynamic scattering mode of LCDs.T. Peter Brody, J. A. Asars and G. D. Dixon at Westinghouse Research Laboratories developed a CdSe (cadmium selenide) TFT, which they used to demonstrate the first CdSe thin-film-transistor liquid-crystal display (TFT LCD).active-matrix liquid-crystal display (AM LCD) using CdSe TFTs in 1974, and then Brody coined the term "active matrix" in 1975.high-resolution and high-quality electronic visual display devices use TFT-based active matrix displays.

The circuit layout process of a TFT-LCD is very similar to that of semiconductor products. However, rather than fabricating the transistors from silicon, that is formed into a crystalline silicon wafer, they are made from a thin film of amorphous silicon that is deposited on a glass panel. The silicon layer for TFT-LCDs is typically deposited using the PECVD process.

Polycrystalline silicon is sometimes used in displays requiring higher TFT performance. Examples include small high-resolution displays such as those found in projectors or viewfinders. Amorphous silicon-based TFTs are by far the most common, due to their lower production cost, whereas polycrystalline silicon TFTs are more costly and much more difficult to produce.

The twisted nematic display is one of the oldest and frequently cheapest kind of LCD display technologies available. TN displays benefit from fast pixel response times and less smearing than other LCD display technology, but suffer from poor color reproduction and limited viewing angles, especially in the vertical direction. Colors will shift, potentially to the point of completely inverting, when viewed at an angle that is not perpendicular to the display. Modern, high end consumer products have developed methods to overcome the technology"s shortcomings, such as RTC (Response Time Compensation / Overdrive) technologies. Modern TN displays can look significantly better than older TN displays from decades earlier, but overall TN has inferior viewing angles and poor color in comparison to other technology.

The transmittance of a pixel of an LCD panel typically does not change linearly with the applied voltage,sRGB standard for computer monitors requires a specific nonlinear dependence of the amount of emitted light as a function of the RGB value.

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.

Less expensive PVA panels often use dithering and FRC, whereas super-PVA (S-PVA) panels all use at least 8 bits per color component and do not use color simulation methods.BRAVIA LCD TVs offer 10-bit and xvYCC color support, for example, the Bravia X4500 series. S-PVA also offers fast response times using modern RTC technologies.

A technology developed by Samsung is Super PLS, which bears similarities to IPS panels, has wider viewing angles, better image quality, increased brightness, and lower production costs. PLS technology debuted in the PC display market with the release of the Samsung S27A850 and S24A850 monitors in September 2011.

TFT dual-transistor pixel or cell technology is a reflective-display technology for use in very-low-power-consumption applications such as electronic shelf labels (ESL), digital watches, or metering. DTP involves adding a secondary transistor gate in the single TFT cell to maintain the display of a pixel during a period of 1s without loss of image or without degrading the TFT transistors over time. By slowing the refresh rate of the standard frequency from 60 Hz to 1 Hz, DTP claims to increase the power efficiency by multiple orders of magnitude.

Due to the very high cost of building TFT factories, there are few major OEM panel vendors for large display panels. The glass panel suppliers are as follows:

External consumer display devices like a TFT LCD feature one or more analog VGA, DVI, HDMI, 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 like CVBS, VGA, DVI, HDMI, 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 backlight is usually included on the same controller board.

The low level interface of STN, DSTN, or TFT display panels use either single ended TTL 5 V signal for older displays or TTL 3.3 V for slightly newer displays that transmits the pixel clock, horizontal sync, vertical sync, digital red, digital green, digital blue in parallel. Some models (for example the AT070TN92) also feature input/display enable, horizontal scan direction and vertical scan direction signals.

New and large (>15") TFT displays often use LVDS signaling that transmits the same contents as the parallel interface (Hsync, Vsync, RGB) but will put control and RGB bits into a number of serial transmission lines synchronized to a clock whose rate is equal to the pixel rate. LVDS 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 inverted in order to maintain DC balance. Low-cost TFT displays often have three data lines and therefore only directly support 18 bits per pixel. Upscale displays have four or five data lines to support 24 bits per pixel (truecolor) or 30 bits per pixel respectively. Panel manufacturers are slowly replacing LVDS with Internal DisplayPort and Embedded DisplayPort, which allow sixfold reduction of the number of differential pairs.

The bare display panel will only accept a digital video signal at the resolution determined by the panel pixel matrix designed at manufacture. Some screen panels will ignore the LSB bits of the color information to present a consistent interface (8 bit -> 6 bit/color x3).

Kawamoto, H. (2012). "The Inventors of TFT Active-Matrix LCD Receive the 2011 IEEE Nishizawa Medal". Journal of Display Technology. 8 (1): 3–4. Bibcode:2012JDisT...8....3K. doi:10.1109/JDT.2011.2177740. ISSN 1551-319X.

K. H. Lee; H. Y. Kim; K. H. Park; S. J. Jang; I. C. Park & J. Y. Lee (June 2006). "A Novel Outdoor Readability of Portable TFT-LCD with AFFS Technology". SID Symposium Digest of Technical Papers. AIP. 37 (1): 1079–82. doi:10.1889/1.2433159. S2CID 129569963.

Glass substrate with ITO electrodes. The shapes of these electrodes will determine the shapes that will appear when the LCD is switched ON. Vertical ridges etched on the surface are smooth.

A liquid-crystal display (LCD) is a flat-panel display or other electronically modulated optical device that uses the light-modulating properties of liquid crystals combined with polarizers. Liquid crystals do not emit light directlybacklight or reflector to produce images in color or monochrome.seven-segment displays, as in a digital clock, are all good examples of devices with these displays. They use the same basic technology, except that arbitrary images are made from a matrix of small pixels, while other displays have larger elements. LCDs can either be normally on (positive) or off (negative), depending on the polarizer arrangement. For example, a character positive LCD with a backlight will have black lettering on a background that is the color of the backlight, and a character negative LCD will have a black background with the letters being of the same color as the backlight. Optical filters are added to white on blue LCDs to give them their characteristic appearance.

LCDs are used in a wide range of applications, including LCD televisions, computer monitors, instrument panels, aircraft cockpit displays, and indoor and outdoor signage. Small LCD screens are common in LCD projectors and portable consumer devices such as digital cameras, watches, calculators, and mobile telephones, including smartphones. LCD screens have replaced heavy, bulky and less energy-efficient cathode-ray tube (CRT) displays in nearly all applications. The phosphors used in CRTs make them vulnerable to image burn-in when a static image is displayed on a screen for a long time, e.g., the table frame for an airline flight schedule on an indoor sign. LCDs do not have this weakness, but are still susceptible to image persistence.

Each pixel of an LCD typically consists of a layer of molecules aligned between two transparent electrodes, often made of Indium-Tin oxide (ITO) and two polarizing filters (parallel and perpendicular polarizers), the axes of transmission of which are (in most of the cases) perpendicular to each other. Without the liquid crystal between the polarizing filters, light passing through the first filter would be blocked by the second (crossed) polarizer. Before an electric field is applied, the orientation of the liquid-crystal molecules is determined by the alignment at the surfaces of electrodes. In a twisted nematic (TN) device, the surface alignment directions at the two electrodes are perpendicular to each other, and so the molecules arrange themselves in a helical structure, or twist. This induces the rotation of the polarization of the incident light, and the device appears gray. If the applied voltage is large enough, the liquid crystal molecules in the center of the layer are almost completely untwisted and the polarization of the incident light is not rotated as it passes through the liquid crystal layer. This light will then be mainly polarized perpendicular to the second filter, and thus be blocked and the pixel will appear black. By controlling the voltage applied across the liquid crystal layer in each pixel, light can be allowed to pass through in varying amounts thus constituting different levels of gray.

The chemical formula of the liquid crystals used in LCDs may vary. Formulas may be patented.Sharp Corporation. The patent that covered that specific mixture expired.

Most color LCD systems use the same technique, with color filters used to generate red, green, and blue subpixels. The LCD color filters are made with a photolithography process on large glass sheets that are later glued with other glass sheets containing a TFT array, spacers and liquid crystal, creating several color LCDs that are then cut from one another and laminated with polarizer sheets. Red, green, blue and black photoresists (resists) are used. All resists contain a finely ground powdered pigment, with particles being just 40 nanometers across. The black resist is the first to be applied; this will create a black grid (known in the industry as a black matrix) that will separate red, green and blue subpixels from one another, increasing contrast ratios and preventing light from leaking from one subpixel onto other surrounding subpixels.Super-twisted nematic LCD, where the variable twist between tighter-spaced plates causes a varying double refraction birefringence, thus changing the hue.

LCD in a Texas Instruments calculator with top polarizer removed from device and placed on top, such that the top and bottom polarizers are perpendicular. As a result, the colors are inverted.

The optical effect of a TN device in the voltage-on state is far less dependent on variations in the device thickness than that in the voltage-off state. Because of this, TN displays with low information content and no backlighting are usually operated between crossed polarizers such that they appear bright with no voltage (the eye is much more sensitive to variations in the dark state than the bright state). As most of 2010-era LCDs are used in television sets, monitors and smartphones, they have high-resolution matrix arrays of pixels to display arbitrary images using backlighting with a dark background. When no image is displayed, different arrangements are used. For this purpose, TN LCDs are operated between parallel polarizers, whereas IPS LCDs feature crossed polarizers. In many applications IPS LCDs have replaced TN LCDs, particularly in smartphones. Both the liquid crystal material and the alignment layer material contain ionic compounds. If an electric field of one particular polarity is applied for a long period of time, this ionic material is attracted to the surfaces and degrades the device performance. This is avoided either by applying an alternating current or by reversing the polarity of the electric field as the device is addressed (the response of the liquid crystal layer is identical, regardless of the polarity of the applied field).

Displays for a small number of individual digits or fixed symbols (as in digital watches and pocket calculators) can be implemented with independent electrodes for each segment.alphanumeric or variable graphics displays are usually implemented with pixels arranged as a matrix consisting of electrically connected rows on one side of the LC layer and columns on the other side, which makes it possible to address each pixel at the intersections. The general method of matrix addressing consists of sequentially addressing one side of the matrix, for example by selecting the rows one-by-one and applying the picture information on the other side at the columns row-by-row. For details on the various matrix addressing schemes see passive-matrix and active-matrix addressed LCDs.

LCDs are manufactured in cleanrooms borrowing techniques from semiconductor manufacturing and using large sheets of glass whose size has increased over time. Several displays are manufactured at the same time, and then cut from the sheet of glass, also known as the mother glass or LCD glass substrate. The increase in size allows more displays or larger displays to be made, just like with increasing wafer sizes in semiconductor manufacturing. The glass sizes are as follows:

Until Gen 8, manufacturers would not agree on a single mother glass size and as a result, different manufacturers would use slightly different glass sizes for the same generation. Some manufacturers have adopted Gen 8.6 mother glass sheets which are only slightly larger than Gen 8.5, allowing for more 50 and 58 inch LCDs to be made per mother glass, specially 58 inch LCDs, in which case 6 can be produced on a Gen 8.6 mother glass vs only 3 on a Gen 8.5 mother glass, significantly reducing waste.AGC Inc., Corning Inc., and Nippon Electric Glass.

In 1922, Georges Friedel described the structure and properties of liquid crystals and classified them in three types (nematics, smectics and cholesterics). In 1927, Vsevolod Frederiks devised the electrically switched light valve, called the Fréedericksz transition, the essential effect of all LCD technology. In 1936, the Marconi Wireless Telegraph company patented the first practical application of the technology, "The Liquid Crystal Light Valve". In 1962, the first major English language publication Molecular Structure and Properties of Liquid Crystals was published by Dr. George W. Gray.RCA found that liquid crystals had some interesting electro-optic characteristics and he realized an electro-optical effect by generating stripe-patterns in a thin layer of liquid crystal material by the application of a voltage. This effect is based on an electro-hydrodynamic instability forming what are now called "Williams domains" inside the liquid crystal.

In the late 1960s, pioneering work on liquid crystals was undertaken by the UK"s Royal Radar Establishment at Malvern, England. The team at RRE supported ongoing work by George William Gray and his team at the University of Hull who ultimately discovered the cyanobiphenyl liquid crystals, which had correct stability and temperature properties for application in LCDs.

The idea of a TFT-based liquid-crystal display (LCD) was conceived by Bernard Lechner of RCA Laboratories in 1968.dynamic scattering mode (DSM) LCD that used standard discrete MOSFETs.

On December 4, 1970, the twisted nematic field effect (TN) in liquid crystals was filed for patent by Hoffmann-LaRoche in Switzerland, (Swiss patent No. 532 261) with Wolfgang Helfrich and Martin Schadt (then working for the Central Research Laboratories) listed as inventors.Brown, Boveri & Cie, its joint venture partner at that time, which produced TN displays for wristwatches and other applications during the 1970s for the international markets including the Japanese electronics industry, which