are lcd monitors hazardous free sample

-“These chemicals are semi-liquid and can get into the environment at any time during manufacturing and recycling, and they are vaporized during burning,” said University of Saskatchewan environmental toxicologist and lead author John Giesy in a press release. “Now we also know that these chemicals are being released by products just by using them.”

-The researchers found the specific monomers isolated from the smartphones were potentially hazardous to animals and the environment. In lab testing, the chemicals were found to have properties known to inhibit animals’ ability to digest nutrients and to disrupt the proper functioning of the gallbladder and thyroid–similar to dioxins and flame retardants which are known to cause toxic effects in humans and wildlife.

-To be clear, the researchers didn’t observe any adverse health effects from the accumulation of liquid crystals in the human body; they only found that these crystals do in fact leak from devices, and that they have the potential to be toxic. “We don’t know yet whether this a problem, but we do know that people are being exposed, and these chemicals have the potential to cause adverse effects,” said Giesy.

-If you crack LCD screens and find the liquid crystal leakage, don’t panic. Just remember that the liquid crystal materials might not be more toxic than your detergents for stove or washroom. Just wash your hands with soup throughout. Never try to play with it or even worse to taste it. The liquid of the cracked computer screen will not evaporate, no emissions worries.

-Any electronics has environment impact and can’t be used landfills. If you want to get rid of old LCD monitors or LCD TVs, give them to electronic collection stations. Let’s the professionals to handle them. They will extract some precious metals/parts and make them into something useful or at least not hazard. FYI, liquid crystal materials are retrievable.

That"s because it"s quite likely that you have a few old computers stashed in their somewhere. In fact, it"s possible that if you"re moving your place of business, you may have stacks of old monitors, PCs, and various other types of outdated and unusable electronics. So, what do you do with them?

That includes your old batteries, too, by the way. And those old computer monitors are actually toxic. That"s right - they can contain up to eight pounds of lead in their glass tubes. Not to mention that the inside of the tubes were coated with toxic phosphorousdust.

Many recycling programs have been established across North America, and they"re dedicated to making sure used monitors aren"t tossed in landfills to rot. And, some states like California, require that these devices and equipment be properly disposed of for recycling.

However, there are some things you should know about what your monitors contain, how they can hurt the environment, and how to find a reliable recycling service. Not all recycling programs are trustworthy, and it"s up to you to find one to whom you can confidently hand over your monitor.

Similar to CRT televisions, CRT monitors use the same core concept and technology. While they performed well for the time, almost everyone has switched to LCD over the years. In fact, it is now almost impossible to find and purchase a new CRT device.

Disposing of them is not simple, however, as the chemicals and components within CRT monitors are hazardous, even toxic, and must be handled and disposed of properly.

If left in a landfill, for example, these monitors slowly degrade, allowing toxic chemicals and heavy metals to enter the soil. From there, they can find their way back into the human ecosystem through plants and animals.

The most notable metal contained in CRT monitors is lead but they also contain cadmium, which is highly toxic, and small amounts of arsenic. Flame retardants used in the construction of many electronics are also highly toxic when disposed of improperly.

LCD monitors have largely replaced CRT in most homes as those dinosaurs went out of production as far back as 2007. But that doesn"t mean the LCD units aren"t detrimental to the environment when illegally dumped or thrown away in a landfill.

While LCD monitors are inherently stable and not a health hazard while being used, once they are disposed of they possess the potential for releasing hazardous material.

The international research team analyzed 362 chemicals used in LCD screens and found that nearly 100 have the potential to be toxic. These particles don"t break down quickly and have "high mobility" in the environment.

In addition, recent research has suggested that liquid crystal monomers - the synthetic chemicals that make LCDs work - contain a variety of toxic chemicals, which tests have shown can leach into the atmosphere.

If you have the tech knowledge, you can also revitalize old monitors for a new cause. If you have the time and patience, there are many ways you can try to extend the usable life of your monitor, as well as the potential to recoup some of its cost.

If your monitor is broken, obsolete, or otherwise useless, however, you will be better off recycling it. This isn"t always an easy process, unfortunately, causing many people to hold onto their old CRT monitors because they aren"t sure what to do with them.

However, you have probably long ago made the switch to LCD and the good news is that there are many recycling programs accept your old LCD monitors, as well as you ancient CRT, for a small fee.

The problem for recyclers is that CRT recycling is an expensive process that is not highly profitable. So, for that reason, many recycling programs must charge a fee to accept CRT monitors and televisions.

Keep in mind, too, that CRT technology was developed long before environmental concerns were a priority in our society, so they aren"t the most recycle-friendly devices.

However, most people are happy to pay a small fee to get these clunky relics out of their homes. Dumping them is illegal in many places, and curbside garbage programs are instructed not to pick them up. That leaves people with one option: bite the bullet and pay the fee.

A word of caution here: while many recycling programs do take these electronics off your hands, that doesn"t mean they"re doing the right thing with them. Some companies make their money by exporting CRT and LCD monitors to developing countries, where they are picked apart, burned, or left to rot.

While you could search online for environmentally-friendly recycling program that specializes in computer monitors, hardware, and other e-waste, we have a much easier solution. Just call the pros at Junk King!

The good news is that a junk recycling service like Junk King offers far more than just genuinely green recycling processes for old computer monitors. In fact, at Junk King, we take much, much more than just monitors and other types of e-waste; we also accept things like broken-down appliances and old furniture and even used mattresses.

We take just about anything and everything except for hazardous waste. And after we pick it up and haul it away for you, your junk is sorted through, organized, and recycled, if possible. In fact, we succeed in getting up to 60 percent of everything we collect a new life elsewhere.

Technology is constantly evolving, bringing us new and better devices that leave us questioning what we ever thought was so great about those old ones in the first place. Last year’s mobile phones, TVs, and computers that use LCD screens are now dated by ever-improving models and a better grade of LCD – so replacing and upgrading the technology is important.

So, what should we do with these old devices and LCD hardware with a lifespan of 10-20 years that we now have lying sad and forgotten in the corner, in the attic, or out on the curb? Recycle them, of course! LCDs have their own regulations for recycling, so here are some tips on how to recycle your old LCD screens and devices.

LCDs that were manufactured before 2009 use cold cathode fluorescent lamps (CCFLs) to backlight the display. These CCFL displays contain mercury, which makes them hazardous to dispose of or incinerate. Other electronic products can contain hazardous chemicals, such as heavy metals and brominated flame retardants. These materials can leak out of landfills and into groundwater, streams, etc., or can be transformed into “super toxicants” while being incinerated. Throwing away these types of devices can clearly be harmful, even today. There are still some harmful chemicals and materials inside electronic devices that will damage the environment if they aren’t disposed of properly—and many times, they aren’t.

Another big problem is that because of the turn-over rate of these electronic devices, LCD screens are just left sitting in landfills. Since they need to be disposed of in certain ways, they’re left to sit and waste away, taking up space in the landfills. Many states have laws prohibiting the disposal of electronic waste in landfills. Because of that, LCDs are likely to sit and rot, or be incinerated in large quantities. They also could be shipped off to other countries that don’t have these prohibiting laws, which is definitely not the best solution to the problem.

Many times, we get new and better gadgets before the current one even needs replacing. That old TV still works, still shows the picture clearly and there’s not a scratch on it. But this new one…well, it’s bigger. It has the Internet capabilities built right in and it can do backflips! Okay, not really, but the point is that we tend to get something new while we still have a perfectly functioning, but slightly older, model. Instead of keeping it in the attic, you can donate it or recycle it to companies and stores in your area that will take it. These places can resell it to people who don’t have the latest backflipping TV, mobile phone or tablet.

Since the issue was raised, there has been much research performed on the best method for recycling LCD screens. Different facilities have different ideas, practices and processes. Some of these processes include removing the hazardous waste materials from the screens/monitors; others believe in completely taking apart the device/screen piece by piece and seeing what can be resold or refurbished, then disposing of the rest in environmentally friendly ways.

Almost 98% of an LCD monitor can be recycled. All plastics are removed to be recycled into new products. Printed circuit boards can be recovered from LCD recycling and smelted to recover valuable metals, while cabling is stripped to reclaim copper and other metals.

Considering how frequently we get new electronic devices, being smart about LCD recycling can make a huge difference. General Digital encourages all of its customers to recycle their used computer monitors and televisions. Learn more about e-cycling from Maryland’s Department of the Environment, and Maine’s Department of Environmental Protection.

I used to work for a laptop manufacturer doing support, and we were instructed that in the event that a customer ever called reporting a leaking LCD we were to IMMEDIATELY tell them to hang up the phone, call emergency services, and get a hazmat team onsite, while we escalated the call to our internal dedicated safety response team. That seems like a pretty harsh response (it"s more severe than what I would have been expected to do for anything short of "My laptop set my house on fire") so I"m inclined to think this stuff isn"t especially safe. It may be true that it"s only a hazard if ingested, though; based on my semi-limited knowledge of the chemistry involved that seems possible. If it were me, though, I"d take the extra cautious route just in case.

(In practice, this basically never happens short of a severe puncture like a blade would cause because of the way these things are manufactured. I"ve actually never personally heard of a situation where an LCD was leaking short of taking a bullet.) EDIT: Let me just make this stronger. This hardly ever happens, ever, anywhere, ever - it"s designed to prevent exactly this sort of problem. Unless you actually witness it in action there is probably no reason to worry about it. See further discussion in comments.

One of the largest recycling problems faced by most countries comes down to the sheer volume of computer electronics that are obsolete and outdated. With technology advances showing no signs of slowing down, it"s no wonder that businesses and home users are constantly upgrading computer monitors.

The first thing that"s important to understand is how big of a problem electronics are. With people replacing phones every year and computers every few years, it shouldn"t come as a surprise that there are mountains of discarded electronics every year.

When e-waste like monitors isn"t properly handled at the end of its life, then exposure to the natural elements alone can cause many of the toxic materials to break down and evaporate into the air.

But even modern LCD monitors contain many different metals and chemicals that are perfectly safe when they are contained. But even small amounts of them in the open air canseriously damage animals, plants, and humans.

When monitors and other computer electronics are illegally dumped, or they end up at a landfill, then all those metals like lead, mercury, and cadmium can ultimately release due to heat, cold, and moisture exposure.

These are not problems that arise suddenly, and contamination often happens over many years with a gradual accumulation of the toxins. Once there are symptoms, a lot of the damage has often been done, and people can be left with permanent health problems.

OK, now that you know that those old monitors in the garage or basement could be a health hazard and that the right thing to do is to recycle computer monitors, it"s time to go through this simple process.

If there are loose cables still attached, or the monitor is still attached to a computer, then make sure you remove all the cables first. You can recycle these as well, but it"s best to keep them separate.

Now is also a good time to check for any other electronic devices like printers, scanners, and DVD players that are just taking up space and never used.

Make sure that your old computer monitors are safely placed in your trunk so that they avoid falling or rolling around. Those external plastics won"t stand up to much force, and you can quickly damage internal components that contain the heavy metals.

If you live in the San Francisco Bay Area, then you can bring your old e-waste to the GreenCitizen recycling facility. The company has years of experience in recycling electronic devices and offers competitive rates.

The recycling process for computers and monitors starts with carefully taking apart the electronics into their individual components. There are plenty of plastics, and then there"s the glass and multiple circuit boards.

While some materials in these devices can enter the cycle economy, there are others like lead glass that can"t be reused. These need to be separated and then disposed of at specialist sites using containers that make sure they are sealed indefinitely or until there"s a solution for dealing with it better.

While they might not take care of the overall breakdown of the materials, many of them do offer to take back old computer monitors, printers, hard drives, phones, and laptops for free or a nominal fee.

Many major electronics stores now offer a recycling program where you can drop off computers, laptops, TVs, monitors, and anything electrical that you bought there.

This should be your first option if you have computer monitors that are relatively modern and still in working order. Many charities and Goodwill stores will happily accept electronics that could help out people with little financial means.

Reusing electronics as is without refurbishing or recycling is an ideal choice, especially since there are so many people that can"t afford the latest and greatest in modern technology.

If you"re in the San Francisco Bay Area and have some old monitors from personal home use, then GreenCitizen offers a free drop-off service . And the process couldn"t be any easier.

Then weigh the fee items and fill out the mail-in recycling form. All that"s left is to pay the fee online and receive the shipping instructions. You can then use your preferred shipping company to have your old computer monitors and other equipment sent to the recycling center.

GreenCitizen has created a Green Directoryof recycling service providers around the country with an easy-to-use search function. You simply enter what you need to recycle and what your zip code is, and you"ll receive the nearest company that offers a business collection or drop-off program.

Yes, old CRT monitors can be recycled. In most cases, it"s not possible to reuse them with modern computers, but they contain toxic metals that should end up in the trash or landfill.

The penalty for not recycling old computer monitors is different from state to state and county to county. In many cases, it ranges from $50 to several hundred dollars, which should be enough incentive not to throw it in the trash.

Yes, a monitor can store data. This is typically more common with smart TVs, but some monitors also have similar functions that could store login details for streaming services. It"s important that you use a data destruction service for such devices.

The easiest way to get rid of working electronics for free is to drop them off at Goodwill or a charity store. If they are relatively new, then you may also be able to recycle them for free at a local recycling center.

I strongly suggest starting your recycling effort with GreenCitizen, and even if they aren"t close enough to deal with your old computer screen, laptop, or other devices, our Green Directory will be able to point you to your closest service.

A.In 2003, the Electronic Waste Recycling Act established a funding system for the collection and recycling of certain electronic wastes. Key elements of the Electronic Waste Recycling Act of 2003 include the collection of an electronic waste recycling fee at the retail point of sale of covered products and requirements on manufacturers to provide consumer information regarding recycling opportunities. The intent of this program is to make recycling options for consumers more convenient so products containing toxic compounds are disposed of appropriately. For more information on this law and its implementation, please seehttp://http://www.calrecycle.ca.gov/Electronics/.

Beginning in 2005, an Electronic Waste Recycling Fee will be assessed on certain "covered" electronic devices sold in California. "Covered" devices include most video display products, such as computer monitors and televisions. The fee will be collected at the time of retail sale, including Internet and catalog sales, to California consumers and is not reimbursable to consumers.

A.After February 2006, it is illegal for residents and small businesses to dispose of fluorescent lamps, household batteries, and other “Universal Waste” in the trash. Under the law , “Universal Waste” is defined as batteries, mercury thermostats, fluorescent lights, cathode ray tube devices (computer monitors, televisions), mercury thermometers, and other products containing mercury or other heavy metals. This list includes:

Electronic devices, such as televisions and computer monitors, computers, printers, VCRs, cell phones, telephones, radios, and microwave ovens. These devices often contain heavy metals like lead, cadmium, copper, and chromium.

A. Computer monitors and televisions with Cathode Ray Tubes (CRTs) have been deemed hazardous waste by the California Department of Toxic Substance Control and, therefore, cannot be disposed of in a landfill. Each CRT contains 5 to 7 pounds of lead, as well as cadmium, silver, gold, and other heavy metals and toxic compounds. Lab studies have shown the potential for these compounds and elements to leach out of the computer equipment into the landfill’s outflow and cause groundwater contamination.

A. Almost any product with a circuit board is now banned from the landfill and considered universal waste and, as such, requires special handling. Like used motor oil and paint, universal waste is a kind of hazardous waste. It is illegal to dispose of hazardous waste in the garbage. These products contain toxic substances, such as mercury, lead, and cadmium. Mercury, released into the environment through the improper disposal of mercury-containing products, is a known neurotoxin.

A.Since electronic waste is subject to California’s hazardous waste regulations, it must be reused, recycled, or disposed of properly. Please do not put these items in the garbage or curbside recycling bins. A complete list of universal waste products and information about disposal and recycling options, is available on the DTSC website at http://www.dtsc.ca.gov/HazardousWaste/UniversalWaste/index.cfm.

A.If you are a department on campus, you can place calculators, CDs, cellphones, PDAs, telephones, wireless devices, empty printer/toner cartridges, and other e-waste in the green Electronic Devices buckets (for more information and locations click here). For larger electronics, contact Surplus Property.

A. Residential customers, students, and community members may bring their computer monitors, televisions, laptop computers, and plasma screens to PSSI at 339 Bonair Siding, during regular business hours, Monday through Friday from 8 am to 4 pm (phone: 321-4236 or pssi@pssirecycling.com). Please do not leave them at the Stanford Recycling Drop-Off Center. It will be considered abandoned waste and we will receive a violation. We are able to accept these items in our office free of charge because of California’s Electronic Waste Law (2005). The Law requires the consumer to declare that the item was purchased and used in California. To make this declaration, you, the consumer, must provide your name and physical address (P.O. Boxes not acceptable) for a State of California form in our office. Since the recycling of these items is funded through the State, the State must ensure that it is funding recycling by California residents and businesses.

A. Below are a few manufacturers of electronics that have taken the lead to take back their old equipment and/or be involved in the reuse and recycling of their equipment.

You should also be aware of products that contain mercury and are not safe for use. Some skin lightening creams, for example, contain mercury and should not be used.

EPA encourages consumers to consider alternatives to products that contain mercury. For example, digital non-mercury thermometers are a safer alternative to mercury thermometers.

The following products may contain mercury. Unless otherwise noted these products need to be properly disposed at household hazardous waste collection centers if they contain mercury. Consult your local or state collection program.

Older model electric appliances including chest freezers, space heaters, clothes dryers, clothes irons and washing machines may contain mercury switches that turn the device on or off, or turn a light on or off. When disposing of larger appliances, either contact your state or local household hazardous waste collection center for advice on recycling or disposal, or contact a local appliance recycler.

Switches are products or devices that open or close an electrical circuit, or a liquid or gas valve. They are used in trunks and hoods, heated car rear windows, acceleration sensors for air bags and seatbelts and anti-lock braking systems. Automotive relays are products or devices that open or close electrical contacts to control the operation of other devices in the same or another electrical circuit.

Mercury is used in LCD screens and monitors. It is also used in laptop screen shutoffs. Televisions manufactured before 1991 may also contain mercury switches. These products need to be properly disposed at household hazardous waste collection centers.

Most skin creams do not contain mercury compounds. Those that do are generally imported from outside the U.S. and are sold as skin lightening or freckle creams. Do not use of skin cream that contains mercury as this can lead to skin rashes or poisoning because mercury can be absorbed through the skin.

Mercury thermostats are unlikely to break or leak mercury while is use, but they need to be properly disposed of when being replaced. Old thermostats should be taken to a state or local household hazardous waste collection center for recycling. Non-mercury thermostats are commercially available.

Many states and local agencies have developed collection/exchange programs for mercury-containing devices such as thermometers, manometers, and thermostats. Some counties and cities also have household hazardous waste collection programs.  For information about these programs, contact your local officials to find out when and where a collection will be held in your area.

Under the Resource Conservation and Recovery Act, some widely generated hazardous wastes, including mercury-containing wastes like mercury-containing light bulbs, certain spent batteries, thermostats, barometers, manometers, temperature and pressure gauges, and certain switches, are designated as "universal wastes." Businesses and industries that qualify as universal waste handlers must follow specific requirements for storing, transporting and disposing of these wastes. Households are exempt from these regulations.

Note that some states and local jurisdictions have elected to pass regulations that are more stringent than the federal hazardous waste regulations. Several states and municipalities do not recognize the exemption for households; others regulate all fluorescent bulbs as hazardous, regardless of their mercury content. For example, Vermont bans all mercury-containing waste from landfills, including mercury-containing waste generated by households.

The Shelby County Household Hazardous Waste Facility is available for residents of Shelby County to bring their hazardous waste items. It is located on 6305 Haley Road in Memphis, Tennessee (38134). Currently, the facility is open to residents on Tuesdays, Thursdays, and Saturdays from 8:00 am to 1:00 pm, excluding the holidays of Thanksgiving, Christmas, and New Year’s Day. For further information, call (901)222-7729. The Household Hazardous Waste Facility Acceptable& Not Acceptable products list. Helping Protect Our Environment.

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, digital clocks, calculators, and mobile telephones, including smartphones. LCD screens are also used on consumer electronics products such as DVD players, video game devices and clocks. LCD screens have replaced heavy, bulky cathode-ray tube (CRT) displays in nearly all applications. LCD screens are available in a wider range of screen sizes than CRT and plasma displays, with LCD screens available in sizes ranging from tiny digital watches to very large television receivers. LCDs are slowly being replaced by OLEDs, which can be easily made into different shapes, and have a lower response time, wider color gamut, virtually infinite color contrast and viewing angles, lower weight for a given display size and a slimmer profile (because OLEDs use a single glass or plastic panel whereas LCDs use two glass panels; the thickness of the panels increases with size but the increase is more noticeable on LCDs) and potentially lower power consumption (as the display is only "on" where needed and there is no backlight). OLEDs, however, are more expensive for a given display size due to the very expensive electroluminescent materials or phosphors that they use. Also due to the use of phosphors, OLEDs suffer from screen burn-in and there is currently no way to recycle OLED displays, whereas LCD panels can be recycled, although the technology required to recycle LCDs is not yet widespread. Attempts to maintain the competitiveness of LCDs are quantum dot displays, marketed as SUHD, QLED or Triluminos, which are displays with blue LED backlighting and a Quantum-dot enhancement film (QDEF) that converts part of the blue light into red and green, offering similar performance to an OLED display at a lower price, but the quantum dot layer that gives these displays their characteristics can not yet be recycled.

Since LCD screens do not use phosphors, they rarely suffer 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 are, however, susceptible to image persistence.battery-powered electronic equipment more efficiently than a CRT can be. By 2008, annual sales of televisions with LCD screens exceeded sales of CRT units worldwide, and the CRT became obsolete for most purposes.

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, along with OLED displays, 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 soon produced the first digital quartz wristwatches with TN-LCDs and numerous other products. James Fergason, while working with Sardari Arora and Alfred Saupe at Kent State University Liquid Crystal Institute, filed an identical patent in the United States on April 22, 1971.ILIXCO (now LXD Incorporated), produced LCDs based on the TN-effect, which soon superseded the poor-quality DSM types due to improvements of lower operating voltages and lower power consumption. Tetsuro Hama and Izuhiko Nishimura of Seiko received a US patent dated February 1971, for an electronic wristwatch incorporating a TN-LCD.

In 1972, the concept of the active-matrix thin-film transistor (TFT) liquid-crystal display panel was prototyped in the United States by T. Peter Brody"s team at Westinghouse, in Pittsburgh, Pennsylvania.Westinghouse Research Laboratories demonstrated the first thin-film-transistor liquid-crystal display (TFT LCD).high-resolution and high-quality electronic visual display devices use TFT-based active matrix displays.active-matrix liquid-crystal display (AM LCD) in 1974, and then Brody coined the term "active matrix" in 1975.

In 1972 North American Rockwell Microelectronics Corp introduced the use of DSM LCDs for calculators for marketing by Lloyds Electronics Inc, though these required an internal light source for illumination.Sharp Corporation followed with DSM LCDs for pocket-sized calculators in 1973Seiko and its first 6-digit TN-LCD quartz wristwatch, and Casio"s "Casiotron". Color LCDs based on Guest-Host interaction were invented by a team at RCA in 1968.TFT LCDs similar to the prototypes developed by a Westinghouse team in 1972 were patented in 1976 by a team at Sharp consisting of Fumiaki Funada, Masataka Matsuura, and Tomio Wada,

In 1983, researchers at Brown, Boveri & Cie (BBC) Research Center, Switzerland, invented the passive matrix-addressed LCDs. H. Amstutz et al. were listed as inventors in the corresponding patent applications filed in Switzerland on July 7, 1983, and October 28, 1983. Patents were granted in Switzerland CH 665491, Europe EP 0131216,

The first color LCD televisions were developed as handheld televisions in Japan. In 1980, Hattori Seiko"s R&D group began development on color LCD pocket televisions.Seiko Epson released the first LCD television, the Epson TV Watch, a wristwatch equipped with a small active-matrix LCD television.dot matrix TN-LCD in 1983.Citizen Watch,TFT LCD.computer monitors and LCD televisions.3LCD projection technology in the 1980s, and licensed it for use in projectors in 1988.compact, full-color LCD projector.

In 1990, under different titles, inventors conceived electro optical effects as alternatives to twisted nematic field effect LCDs (TN- and STN- LCDs). One approach was to use interdigital electrodes on one glass substrate only to produce an electric field essentially parallel to the glass substrates.Germany by Guenter Baur et al. and patented in various countries.Hitachi work out various practical details of the IPS technology to interconnect the thin-film transistor array as a matrix and to avoid undesirable stray fields in between pixels.

Hitachi also improved the viewing angle dependence further by optimizing the shape of the electrodes (Super IPS). NEC and Hitachi become early manufacturers of active-matrix addressed LCDs based on the IPS technology. This is a milestone for implementing large-screen LCDs having acceptable visual performance for flat-panel computer monitors and television screens. In 1996, Samsung developed the optical patterning technique that enables multi-domain LCD. Multi-domain and In Plane Switching subsequently remain the dominant LCD designs through 2006.South Korea and Taiwan,

In 2007 the image quality of LCD televisions surpassed the image quality of cathode-ray-tube-based (CRT) TVs.LCD TVs were projected to account 50% of the 200 million TVs to be shipped globally in 2006, according to Displaybank.Toshiba announced 2560 × 1600 pixels on a 6.1-inch (155 mm) LCD panel, suitable for use in a tablet computer,transparent and flexible, but they cannot emit light without a backlight like OLED and microLED, which are other technologies that can also be made flexible and transparent.

In 2016, Panasonic developed IPS LCDs with a contrast ratio of 1,000,000:1, rivaling OLEDs. This technology was later put into mass production as dual layer, dual panel or LMCL (Light Modulating Cell Layer) LCDs. The technology uses 2 liquid crystal layers instead of one, and may be used along with a mini-LED backlight and quantum dot sheets.

Since LCDs produce no light of their own, they require external light to produce a visible image.backlight. Active-matrix LCDs are almost always backlit.Transflective LCDs combine the features of a backlit transmissive display and a reflective display.

CCFL: The LCD panel is lit either by two cold cathode fluorescent lamps placed at opposite edges of the display or an array of parallel CCFLs behind larger displays. A diffuser (made of PMMA acrylic plastic, also known as a wave or light guide/guiding plateinverter to convert whatever DC voltage the device uses (usually 5 or 12 V) to ≈1000 V needed to light a CCFL.

EL-WLED: The LCD panel is lit by a row of white LEDs placed at one or more edges of the screen. A light diffuser (light guide plate, LGP) is then used to spread the light evenly across the whole display, similarly to edge-lit CCFL LCD backlights. The diffuser is made out of either PMMA plastic or special glass, PMMA is used in most cases because it is rugged, while special glass is used when the thickness of the LCD is of primary concern, because it doesn"t expand as much when heated or exposed to moisture, which allows LCDs to be just 5mm thick. Quantum dots may be placed on top of the diffuser as a quantum dot enhancement film (QDEF, in which case they need a layer to be protected from heat and humidity) or on the color filter of the LCD, replacing the resists that are normally used.

WLED array: The LCD panel is lit by a full array of white LEDs placed behind a diffuser behind the panel. LCDs that use this implementation will usually have the ability to dim or completely turn off the LEDs in the dark areas of the image being displayed, effectively increasing the contrast ratio of the display. The precision with which this can be done will depend on the number of dimming zones of the display. The more dimming zones, the more precise the dimming, with less obvious blooming artifacts which are visible as dark grey patches surrounded by the unlit areas of the LCD. As of 2012, this design gets most of its use from upscale, larger-screen LCD televisions.

RGB-LED array: Similar to the WLED array, except the panel is lit by a full array of RGB LEDs. While displays lit with white LEDs usually have a poorer color gamut than CCFL lit displays, panels lit with RGB LEDs have very wide color gamuts. This implementation is most popular on professional graphics editing LCDs. As of 2012, LCDs in this category usually cost more than $1000. As of 2016 the cost of this category has drastically reduced and such LCD televisions obtained same price levels as the former 28" (71 cm) CRT based categories.

Monochrome LEDs: such as red, green, yellow or blue LEDs are used in the small passive monochrome LCDs typically used in clocks, watches and small appliances.

Mini-LED: Backlighting with Mini-LEDs can support over a thousand of Full-area Local Area Dimming (FLAD) zones. This allows deeper blacks and higher contrast ratio.MicroLED.)

Today, most LCD screens are being designed with an LED backlight instead of the traditional CCFL backlight, while that backlight is dynamically controlled with the video information (dynamic backlight control). The combination with the dynamic backlight control, invented by Philips researchers Douglas Stanton, Martinus Stroomer and Adrianus de Vaan, simultaneously increases the dynamic range of the display system (also marketed as HDR, high dynamic range television or FLAD, full-area local area dimming).

The LCD backlight systems are made highly efficient by applying optical films such as prismatic structure (prism sheet) to gain the light into the desired viewer directions and reflective polarizing films that recycle the polarized light that was formerly absorbed by the first polarizer of the LCD (invented by Philips researchers Adrianus de Vaan and Paulus Schaareman),

Due to the LCD layer that generates the desired high resolution images at flashing video speeds using very low power electronics in combination with LED based backlight technologies, LCD technology has become the dominant display technology for products such as televisions, desktop monitors, notebooks, tablets, smartphones and mobile phones. Although competing OLED technology is pushed to the market, such OLED displays do not feature the HDR capabilities like LCDs in combination with 2D LED backlight technologies have, reason why the annual market of such LCD-based products is still growing faster (in volume) than OLED-based products while the efficiency of LCDs (and products like portable computers, mobile phones and televisions) may even be further improved by preventing the light to be absorbed in the colour filters of the LCD.

A pink elastomeric connector mating an LCD panel to circuit board traces, shown next to a centimeter-scale ruler. The conductive and insulating layers in the black stripe are very small.

A standard television receiver screen, a modern LCD panel, has over six million pixels, and they are all individually powered by a wire network embedded in the screen. The fine wires, or pathways, form a grid with vertical wires across the whole screen on one side of the screen and horizontal wires across the whole screen on the other side of the screen. To this grid each pixel has a positive connection on one side and a negative connection on the other side. So the total amount of wires needed for a 1080p display is 3 x 1920 going vertically and 1080 going horizontally for a total of 6840 wires horizontally and vertically. That"s three for red, green and blue and 1920 columns of pixels for each color for a total of 5760 wires going vertically and 1080 rows of wires going horizontally. For a panel that is 28.8 inches (73 centimeters) wide, that means a wire density of 200 wires per inch along the horizontal edge.

The LCD panel is powered by LCD drivers that are carefully matched up with the edge of the LCD panel at the factory level. The drivers may be installed using several methods, the most common of which are COG (Chip-On-Glass) and TAB (Tape-automated bonding) These same principles apply also for smartphone screens that are much smaller than TV screens.anisotropic conductive film or, for lower densities, elastomeric connectors.

Monochrome and later color passive-matrix LCDs were standard in most early laptops (although a few used plasma displaysGame Boyactive-matrix became standard on all laptops. The commercially unsuccessful Macintosh Portable (released in 1989) was one of the first to use an active-matrix display (though still monochrome). Passive-matrix LCDs are still used in the 2010s for applications less demanding than laptop computers and TVs, such as inexpensive calculators. In particular, these are used on portable devices where less information content needs to be displayed, lowest power consumption (no backlight) and low cost are desired or readability in direct sunlight is needed.

Displays having a passive-matrix structure are employing Crosstalk between activated and non-activated pixels has to be handled properly by keeping the RMS voltage of non-activated pixels below the threshold voltage as discovered by Peter J. Wild in 1972,

STN LCDs have to be continuously refreshed by alternating pulsed voltages of one polarity during one frame and pulses of opposite polarity during the next frame. Individual pixels are addressed by the corresponding row and column circuits. This type of display is called response times and poor contrast are typical of passive-matrix addressed LCDs with too many pixels and driven according to the "Alt & Pleshko" drive scheme. Welzen and de Vaan also invented a non RMS drive scheme enabling to drive STN displays with video rates and enabling to show smooth moving video images on an STN display.

Bistable LCDs do not require continuous refreshing. Rewriting is only required for picture information changes. In 1984 HA van Sprang and AJSM de Vaan invented an STN type display that could be operated in a bistable mode, enabling extremely high resolution images up to 4000 lines or more using only low voltages.

High-resolution color displays, such as modern LCD computer monitors and televisions, use an active-matrix structure. A matrix of thin-film transistors (TFTs) is added to the electrodes in contact with the LC layer. Each pixel has its own dedicated transistor, allowing each column line to access one pixel. When a row line is selected, all of the column lines are connected to a row of pixels and voltages corresponding to the picture information are driven onto all of the column lines. The row line is then deactivated and the next row line is selected. All of the row lines are selected in sequence during a refresh operation. Active-matrix addressed displays look brighter and sharper than passive-matrix addressed displays of the same size, and generally have quicker response times, producing much better images. Sharp produces bistable reflective LCDs with a 1-bit SRAM cell per pixel that only requires small amounts of power to maintain an image.

Segment LCDs can also have color by using Field Sequential Color (FSC LCD). This kind of displays have a high speed passive segment LCD panel with an RGB backlight. The backlight quickly changes color, making it appear white to the naked eye. The LCD panel is synchronized with the backlight. For example, to make a segment appear red, the segment is only turned ON when the backlight is red, and to make a segment appear magenta, the segment is turned ON when the backlight is blue, and it continues to be ON while the backlight becomes red, and it turns OFF when the backlight becomes green. To make a segment appear black, the segment is always turned ON. An FSC LCD divides a color image into 3 images (one Red, one Green and one Blue) and it displays them in order. Due to persistence of vision, the 3 monochromatic images appear as one color image. An FSC LCD needs an LCD panel with a refresh rate of 180 Hz, and the response time is reduced to just 5 milliseconds when compared with normal STN LCD panels which have a response time of 16 milliseconds.

Samsung introduced UFB (Ultra Fine & Bright) displays back in 2002, utilized the super-birefringent effect. It has the luminance, color gamut, and most of the contrast of a TFT-LCD, but only consumes as much power as an STN display, according to Samsung. It was being used in a variety of Samsung cellular-telephone models produced until late 2006, when Samsung stopped producing UFB displays. UFB displays were also used in certain models of LG mobile phones.

In-plane switching is an LCD technology that aligns the liquid crystals in a plane parallel to the glass substrates. In this method, the electrical field is applied through opposite electrodes on the same glass substrate, so that the liquid crystals can be reoriented (switched) essentially in the same plane, although fringe fields inhibit a homogeneous reorientation. This requires two transistors for each pixel instead of the single transistor needed for a standard thin-film transistor (TFT) display. The IPS technology is used in everything from televisions, computer monitors, and even wearable devices, especially almost all LCD smartphone panels are IPS/FFS mode. IPS displays belong to the LCD panel family screen types. The other two types are VA and TN. Before LG Enhanced IPS was introduced in 2001 by Hitachi as 17" monitor in Market, the additional transistors resulted in blocking more transmission area, thus requiring a brighter backlight and consuming more power, making this type of display less desirable for notebook computers. Panasonic Himeji G8.5 was using an enhanced version of IPS, also LGD in Korea, then currently the world biggest LCD panel manufacture BOE in China is also IPS/FFS mode TV panel.

In 2011, LG claimed the smartphone LG Optimus Black (IPS LCD (LCD NOVA)) has the brightness up to 700 nits, while the competitor has only IPS LCD with 518 nits and double an active-matrix OLED (AMOLED) display with 305 nits. LG also claimed the NOVA display to be 50 percent more efficient than regular LCDs and to consume only 50 percent of the power of AMOLED displays when producing white on screen.

This pixel-layout is found in S-IPS LCDs. A chevron shape is used to widen the viewing cone (range of viewing directions with good contrast and low color shift).

Vertical-alignment displays are a form of LCDs in which the liquid crystals naturally align vertically to the glass substrates. When no voltage is applied, the liquid crystals remain perpendicular to the substrate, creating a black display between crossed polarizers. When voltage is applied, the liquid crystals shift to a tilted position, allowing light to pass through and create a gray-scale display depending on the amount of tilt generated by the electric field. It has a deeper-black background, a higher contrast ratio, a wider viewing angle, and better image quality at extreme temperatures than traditional twisted-nematic displays.

Blue phase mode LCDs have been shown as engineering samples early in 2008, but they are not in mass-production. The physics of blue phase mode LCDs suggest that very short switching times (≈1 ms) can be achieved, so time sequential color control can possibly be realized and expensive color filters would be obsolete.

Some LCD panels have defective transistors, causing permanently lit or unlit pixels which are commonly referred to as stuck pixels or dead pixels respectively. Unlike integrated circuits (ICs), LCD panels with a few defective transistors are usually still usable. Manufacturers" policies for the acceptable number of defective pixels vary greatly. At one point, Samsung held a zero-tolerance policy for LCD monitors sold in Korea.ISO 13406-2 standard.

Dead pixel policies are often hotly debated between manufacturers and customers. To regulate the acceptability of defects and to protect the end user, ISO released the ISO 13406-2 standard,ISO 9241, specifically ISO-9241-302, 303, 305, 307:2008 pixel defects. However, not every LCD manufacturer conforms to the ISO standard and the ISO standard is quite often interpreted in different ways. LCD panels are more likely to have defects than most ICs due to their larger size. For example, a 300 mm SVGA LCD has 8 defects and a 150 mm wafer has only 3 defects. However, 134 of the 137 dies on the wafer will be acceptable, whereas rejection of the whole LCD panel would be a 0% yield. In recent years, quality control has been improved. An SVGA LCD panel with 4 defective pixels is usually considered defective and customers can request an exchange for a new one.

Some manufacturers, notably in South Korea where some of the largest LCD panel manufacturers, such as LG, are located, now have a zero-defective-pixel guarantee, which is an extra screening process which can then determine "A"- and "B"-grade panels.clouding (or less commonly mura), which describes the uneven patches of changes in luminance. It is most visible in dark or black areas of displayed scenes.

The zenithal bistable device (ZBD), developed by Qinetiq (formerly DERA), can retain an image without power. The crystals may exist in one of two stable orientations ("black" and "white") and power is only required to change the image. ZBD Displays is a spin-off company from QinetiQ who manufactured both grayscale and color ZBD devices. Kent Displays has also developed a "no-power" display that uses polymer stabilized cholesteric liquid crystal (ChLCD). In 2009 Kent demonstrated the use of a ChLCD to cover the entire surface of a mobile phone, allowing it to change colors, and keep that color even when power is removed.

In 2004, researchers at the University of Oxford demonstrated two new types of zero-power bistable LCDs based on Zenithal bistable techniques.e.g., BiNem technology, are based mainly on the surface properties and need specific weak anchoring materials.

Resolution The resolution of an LCD is expressed by the number of columns and rows of pixels (e.g., 1024×768). Each pixel is usually composed 3 sub-pixels, a red, a green, and a blue one. This had been one of the few features of LCD performance that remained uniform among different designs. However, there are newer designs that share sub-pixels among pixels and add Quattron which attempt to efficiently increase the perceived resolution of a display without increasing the actual resolution, to mixed results.

Spatial performance: For a computer monitor or some other display that is being viewed from a very close distance, resolution is often expressed in terms of dot pitch or pixels per inch, which is consistent with the printing industry. Display density varies per application, with televisions generally having a low density for long-distance viewing and portable devices having a high density for close-range detail. The Viewing Angle of an LCD may be important depending on the display and its usage, the limitations of certain display technologies mean the display only displays accurately at certain angles.

Temporal performance: the temporal resolution of an LCD is how well it can display changing images, or the accuracy and the number of times per second the display draws the data it is being given. LCD pixels do not flash on/off between frames, so LCD monitors exhibit no refresh-induced flicker no matter how low the refresh rate.

Color performance: There are multiple terms to describe different aspects of color performance of a display. Color gamut is the range of colors that can be displayed, and color depth, which is the fineness with which the color range is divided. Color gamut is a relatively straight forward feature, but it is rarely discussed in marketing materials except at the professional level. Having a color range that exceeds the content being shown on the screen has no benefits, so displays are only made to perform within or below the range of a certain specification.white point and gamma correction, which describe what color white is and how the other colors are displayed relative to white.

Brightness and contrast ratio: Contrast ratio is the ratio of the brightness of a full-on pixel to a full-off pixel. The LCD itself is only a light valve and does not generate light; the light comes from a backlight that is either fluorescent or a set of LEDs. Brightness is usually stated as the maximum light output of the LCD, which can vary greatly based on the transparency of the LCD and the brightness of the backlight. Brighter backlight allows stronger contrast and higher dynamic range (HDR displays are graded in peak luminance), but there is always a trade-off between brightness and power consumption.

Low power consumption. Depending on the set display brightness and content being displayed, the older CCFT backlit models typically use less than half of the power a CRT monitor of the same size viewing area would use, and the modern LED backlit models typically use 10–25% of the power a CRT monitor would use.

Usually no refresh-rate flicker, because the LCD pixels hold their state between refreshes (which are usually done at 200 Hz or faster, regardless of the input refresh rate).

No theoretical resolution limit. When multiple LCD panels are used together to create a single canvas, each additional panel increases the total resolution of the display, which is commonly called stacked resolution.

As an inherently digital device, the LCD can natively display digital data from a DVI or HDMI connection without requiring conversion to analog. Some LCD panels have native fiber optic inputs in addition to DVI and HDMI.

Limited viewing angle in some older or cheaper monitors, causing color, saturation, contrast and brightness to vary with user position, even within the intended viewing angle.

Uneven backlighting in some monitors (more common in IPS-types and older TNs), causing brightness distort