lcd panel to replace 11 crt free sample

CRT displays use the same picture tube technology with many enhancements as the first color televisions did more than half a century ago. But old doesn"t necessarily mean obsolete. A good CRT display, such as the Samsung 997DF 19" model shown in Figure 11-1, provides excellent image quality at a reasonable price. CRT displays are an excellent choice for many people, and will remain so for years.

In autumn 2005, Robert finally replaced his beloved Hitachi SuperScan Elite 751 19" CRT display which he had been using as his primary display for six years with a 19" Samsung 930BF LCD display. The Hitachi is a top-notch display, and Robert would have sworn that its image quality was as good then as the day it was first installed. Until, that is, he connected the Samsung 930BF. The difference was startling. The Samsung provided much better brightness, contrast, and color saturation.

Does that mean that a good LCD display always beats a good CRT display, or that current display technology is worlds better than that of six years ago? Nope. It just means that every CRT display even the best models decreases in brightness, contrast, and saturation as it ages. From day to day, the difference is imperceptible, but as the months and years pass the accumulated difference becomes large.

There is a happy ending to this story, though. Robert had been running the Hitachi CRT at 50% brightness and 85% contrast for years. Boosting brightness to 75% and contrast to 100% greatly improved the display quality, so there"s life in it yet. Barbara promptly grabbed the Hitachi for her own office, where it will probably live for another few years.

The CRT is essentially a large glass bottle, flat or nearly so on one end (the screen), tapering to a thin neck at the back, and with nearly all air exhausted. The inside of the screen end is covered with a matrix of millions of tiny phosphor dots (or stripes). A phosphor is a chemical compound that, when struck by electrons, emits visible light of a particular color. Phosphors are organized by groups of three, collectively called a pixel. Each pixel contains one phosphor dot that emits each of the additive primary colors, red, green, and blue. By choosing which dots to illuminate and how brightly to illuminate each, any pixel can be made to emit any one of thousands or millions of discrete colors. The distance between nearest neighbors of the same phosphor color on adjacent rows is called the dot pitch or stripe pitch. A smaller pitch results in a sharper image and the ability to resolve finer detail.

The phosphor dots are excited by one or more electron emitters, called electron guns, located in the neck at the back of the monitor. A gun comprises a heated cathode, which emits electrons, and circuitry that focuses the free electrons into a thin beam.

The deflection yoke is located around the tapered portion of the CRT, between the guns and the screen. This yoke is actually a large electromagnet, which, under the control of the monitor circuitry, is used to steer the electron beam(s) to impinge on the correct phosphor dot at the correct time and with the correct intensity.

The mask sits between the electron guns and the phosphor layer, very close to the latter. This mask may be a sheet of metal with a matrix of fine perforations that correspond to the phosphor dot triads on the screen, called a shadow mask, or a series of fine vertical wires that correspond to phosphors laid down in uninterrupted vertical stripes, called an aperture grill. In practice, and despite the marketing efforts of manufacturers to convince us otherwise, we find that the mask type makes little real difference. Good (read: more expensive) monitors produce good images, regardless of their mask type. Inexpensive monitors produce inferior images, regardless of their mask type.

Screen size is specified in two ways. The nominal size the size by which monitors are advertised and referred to is the diagonal measurement of the tube itself. However, the front bezel of the monitor conceals part of the tube, making the usable size of the monitor less than stated. Various consumer lawsuits have resulted in monitor manufacturers also specifying the Viewable Image Size (VIS), which is the portion of the tube that is actually visible. Typically, VIS is an inch or so less than nominal. For example, a nominal 17" monitor may have a 15.8" VIS. Small differences in VIS for example, 15.8" versus 16" make little practical difference. The smallest monitors still available are 15". While 17" remains the most popular size, 19" models are now so inexpensive that they have nearly overtaken 17" models in unit sales. Monitors 21" and larger are still relatively expensive, and are used primarily by graphics artists and others who require huge displays.

Dot pitch or stripe pitch is measured in millimeters, and specifies the center-to-center distance between the nearest neighboring phosphor dots or stripes of the same color. Smaller pitch means a sharper image that resolves finer detail. Unfortunately, dot pitch, which is used to describe shadow mask monitors, cannot be compared directly to stripe pitch, which is used to describe aperture grill monitors. For equivalent resolution, stripe pitch must be about 90% of dot pitch. That is, a 0.28 mm dot pitch monitor has resolution similar to a 0.25 mm stripe pitch monitor.

Maximum resolution specifies the maximum number of pixels that the monitor can display, which is determined by the physical number of pixels present on the face of the tube. The maximum resolution of many low-end monitors is identical to the optimum resolution for that monitor size. For example, 1024x768 is optimum for 17" monitors, so many low-end 17" monitors provide 1024x768 maximum resolution. Conversely, midrange and high-end monitors may have maximum resolutions higher than practically usable. For example, a high-end 17" monitor may support up to 1600x1200. There is no real benefit to such extreme resolutions, although it can be useful to have one step higher than optimum (e.g., 1280x1024 on a 17" monitor or 1600x1200 on a 19" monitor) available for occasional use for special purposes.

The synchronization range specifies the bandwidth of the monitor, which determines which combinations of resolution, refresh rate, and color depth can be displayed. Synchronization range is specified as two values:

Vertical Scanning Frequency (VSF) is the inverse of the time the monitor requires to display one full screen. VSF (also called refresh rate) is measured in hertz (Hz) and specifies the number of times per second the screen can be redrawn. To avoid screen flicker, the monitor should support at least 70 Hz refresh at the selected resolution. Within reason, higher refresh rates provide a more stable image, but rates beyond 85 or 90 Hz are necessary only for specialized applications such as medical imaging. Most monitors support a wide range of refresh rates, from very low (e.g., 50 Hz) to very high (e.g., 120 to 160 Hz).

Horizontal Scanning Frequency (HSF) is the inverse of the time the monitor requires to display one full scan line. HSF is measured in kilohertz (KHz), and specifies the overall range of bandwidths supported by the monitor. For example, a monitor running 1280x1024 at 85 Hz must display 1024 lines 85 times per second, or 87,040 scan lines per second, or about 87 KHz. In fact, some overhead is involved, so the actual HSF for such a monitor might be 93.5 KHz.

Resolution and refresh rate are interrelated parts of synchronization range of an analog monitor. For a given resolution, increasing the refresh rate increases the number of screens (and accordingly the amount of data) that must be transferred each second. Similarly, for a given refresh rate, increasing the resolution increases the amount of data that must be transferred for each screen. If you increase resolution or refresh rate, you may have to decrease the other to stay within the HSF limit on total bandwidth.

Note that manufacturers often specify maximum resolution and maximum refresh rate independently, without consideration for their interrelatedness. For example, specifications for a 19" monitor may promise 1600x1200 resolution and 160 Hz refresh. Don"t assume that means you can run 1600x1200 at 160 Hz. 160 Hz refresh may be supported only at 640x480 resolution; at 1600x1200, the monitor may support only 70 Hz refresh.

Resolution and refresh rate alone determine the required bandwidth for an analog monitor. Color depth is immaterial, because the color displayed for a given pixel is determined by the analog voltages present on the red, green, and blue lines at the time that pixel is processed. Therefore, at a given resolution and refresh rate, an analog monitor uses exactly the same bandwidth whether the color depth is set to 4, 8, 16, 24, or 32 bits, because the video card converts the digital color data to analog signals before sending it to the monitor. For purely digital monitors, such as LCD displays, greater color depth requires greater bandwidth, because color information is conveyed to a digital monitor as a digital signal.

Monitors use one of three geometries for the front viewing surface. Older monitors used spherical tubes or cylindrical tubes, both of which have noticeably curved surfaces. Flat square tubes (FST) are nearly flat. Other than some "value" models, all current monitors use an FST. Don"t consider buying a monitor that is not FST.

CRTs cost less than LCDs. For the same price as an entry-level 17" LCD, you can buy a midrange 19" CRT or two good 17" CRTs. The pricing differential has somewhat narrowed recently, but LCDs are likely for the foreseeable future to cost more than CRTs with similar size, features, and quality.

LCDs are designed to operate at one resolution, typically 1024x768 for 15" models and 1280x1024 for 17", 18", and 19" models. Although you can run an LCD at lower resolution than it was designed to use, you don"t want to. At nonnative resolution, you must choose between having a sharp image that occupies only a portion of the screen or using pixel extrapolation, which results in a full-screen image with significantly degraded image quality. CRTs, conversely, can operate at various resolutions, which means that you can choose the resolution that suits your own preferences and vision.

A high-quality CRT normally lasts for many years. It"s common for a CRT to remain in use for five years or more, and even ten years is not unheard of. LCDs use an array of cold cathode ray tubes (CCRTs), which are similar to fluorescent tubes, to provide the backlight required to view the image. A failed CCRT is not economically repairable. When a CCRT burns out, the LCD display must be replaced.

CRTs use phosphor pixels, which can be turned on or off almost instantly. LCDs use transistorized pixels that respond more slowly. This slower response may be visible as a smearing or ghosting effect when an LCD displays fast-motion video, such as DVD video or graphics-intensive games. Although better LCDs don"t exhibit this problem, at least not as severely as cheaper models, it is common and intrusive with entry-level LCDs.

CRTs present essentially the same image quality regardless of viewing angle. Conversely, LCDs present their best image quality only within a relatively small viewing angle, although midrange and better LCD models typically have larger viewing angles than entry-level models.

Many graphic artists refuse to use LCDs because the appearance of colors and the relationship between them changes with viewing angle. This problem is particularly acute with inexpensive LCDs, although even premium units exhibit it at least to some extent. The best LCD models are good enough in this respect for routine use, but most who insist on accurate color reproduction still prefer high-quality CRT monitors.

A CRT never has defective pixels. An LCD panel is manufactured as a monolithic item that contains more than a million pixels, and on some LCD panels one or a few of those pixels are defective. Defective pixels may be always-on (white), always-off (black), or some color. People vary in their reaction to defective pixels. Many don"t even notice a defective pixel or two, while others, once they notice a defective pixel, seem to be drawn to that pixel to the exclusion of all else. Most manufacturer warranties specifically exclude some number of defective pixels, typically between five and ten, although the number may vary with display size and, sometimes, with the location of the defective pixels and how closely they are clustered. As long as the display meets those requirements, the manufacturer considers the display to be acceptable. You may or may not find it acceptable.

Although the contrast and brightness of recent high-end LCDs are excellent, most LCDs provide subjectively less vibrant color than a good CRT. This is particularly evident in the darkest and lightest areas, where tones seem to be compressed, which limits subtle gradations between light tones or dark tones that are readily evident on a good CRT. Also, some LCDs add a color cast to what should be neutral light or dark tones. For example, dark neutral tones may appear shifted toward the blue (cooler) or red (warmer) ranges. This problem is less prevalent in high-quality LCDs than in entry-level units, and is also more likely to occur if you are using an analog interface rather than a digital interface.

If your budget is limited, a CRT offers far more bang for the buck than an LCD and, particularly for entry-level models, overall display quality will also be higher.

Remember that a CRT display is a long-term purchase. Even with heavy use, a high-quality CRT can be expected to last five years or more, so buy quality and choose a model that"s likely to keep you happy not just for your current system, but for one or even two systems after that.

Make sure the CRT is big enough, but not too big. We consider 17" models suitable only for casual use or those on the tightest of budgets. For not much more, you can buy a 19" model that you"ll be much happier with. Conversely, make sure your desk or workstation furniture can accommodate the new CRT. Many people have excitedly carried home a new 21" CRT only to find that it literally won"t fit where it needs to. Check physical dimensions and weight carefully before you buy. Large CRTs commonly weigh 50 lbs. or more, and some exceed 100 lbs. That said, if you find yourself debating 17" versus 19" or 19" versus 21", go with the larger model. But note that if your decision is between a cheap larger CRT and a high-quality smaller one for about the same price, you may well be happier with the smaller CRT. A $130 17" CRT beats a $130 19" CRT every time.

Stick with good name brands and buy a midrange or higher model from within that name brand. That doesn"t guarantee that you"ll get a good CRT, but it does greatly increase your chances. The CRT market is extremely competitive. If two similar models differ greatly in price, the cheaper one likely has significantly worse specs. If the specs appear similar, the maker of the cheaper model has cut corners somewhere, whether in component quality, construction quality, or warranty policies.

RECOMMENDED BRANDS Our opinion, which is shared by many, is that NEC-Mitsubishi, Samsung, and ViewSonic make the best CRTs available. Their CRTs, particularly midrange and better models, provide excellent image quality and are quite reliable. You"re likely to be happy with a CRT from any of these manufacturers.

If possible, test the exact CRT you plan to buy (not a floor sample) before you buy it. Ask the local store to endorse the manufacturer"s warranty that is, to agree that if the CRT fails you can bring it back to the store for a replacement rather than dealing with the hassles of returning it to the manufacturer. Mass merchandisers like Best Buy usually won"t do this they try to sell you a service contract instead, which you shouldn"t buy but small local computer stores may agree to endorse the manufacturer"s warranty. If the CRT has hidden damage from rough handling during shipping, that damage will ordinarily be apparent within a month or two of use, if not immediately.

BUY CRTS LOCALLY After shipping costs, it may actually cost less to buy locally, but that is not the main reason for doing so. Buying locally gives you the opportunity to examine the exact CRT you are buying. CRTs vary more between samples than other computer components. Also, CRTs are sometimes damaged in shipping, often without any external evidence on the CRT itself or even the box. Damaged CRTs may arrive DOA, but more often they have been jolted severely enough to cause display problems and perhaps reduced service life, but not complete failure. Buying locally allows you to eliminate a "dud" before you buy it, rather than having to deal with shipping it back to the vendor or manufacturer.

Most mainstream CRT manufacturers produce three Good, Better, and Best models in 17", 19", and 21". In general, the Good model from a first-tier maker corresponds roughly in features, specifications, and price to the Better or Best models from lower-tier makers. For casual use, choose a Good model from a first-tier maker, most of which are very good indeed. If you make heavier demands on your CRT such as sitting in front of it eight hours a day you may find that the Better model from a first-tier maker is the best choice. The Best models from first-tier makers are usually overkill, although they may be necessary if you use the CRT for CAD/CAM or other demanding tasks. Best models often have generally useless features like extremely high resolutions and unnecessarily high refresh rates at moderate resolutions. It"s nice that a Best 17" model can display 1600x1200 resolution, for example, but unless you can float on thermals and dive on rabbits from a mile in the air, that resolution is likely to be unusable. Similarly, a 17" CRT that supports 115 MHz refresh rates at 1024x768 is nice, but in practical terms offers no real advantage over one that supports an 85 or 90 MHz refresh.

Choose the specific CRT you buy based on how it looks to you. Comparing specifications helps narrow the list of candidates, but nothing substitutes for actually looking at the image displayed by the CRT. For example, CRTs with Sony Trinitron tubes have one or two fine horizontal internal wires whose shadows appear on screen. Most people don"t even notice the shadow, but some find it intolerable.

Make sure the CRT has sufficient reserve brightness. CRTs dim as they age, and one of the most common flaws in new CRTs, particularly those from second- and third-tier manufacturers, is inadequate brightness. A CRT that is barely bright enough when new may dim enough to become unusable after a year or two. A new CRT should provide a good image with the brightness set no higher than 50%.

Like all other component manufacturers, CRT makers have come under increasing margin pressures. A few years ago, we felt safe in recommending any CRT from a first-tier maker, because those companies refused to put their names on anything but top-notch products. Alas, first-tier makers have been forced to make manufacturing cost reductions and other compromises to compete with cheap Pacific Rim CRTs.

Accordingly, low-end models from first-tier makers may be of lower quality than they were in the past. The presence of a first-tier maker"s name plate still means that CRT is likely to be of higher quality than a similar no-name CRT, but is no longer a guarantee of top quality. Many first-tier CRTs are actually made in the same Pacific Rim plants that also produce no-name junk, but don"t read too much into that. First-tier CRTs are still differentiated by component quality and the level of quality control they undergo. There is no question in our minds that the first-tier CRTs are easily worth the 10% to 20% price premium they command relative to lesser brands. In fact, we think it is worth the extra cost to buy not just a first-tier CRT, but a midrange first-tier CRT.

TV repair costs between $60 and $350 with most spending $207 on average for LCD, LED, plasma, and 4K TVs; costs are higher if repairing older DLP, projection, and HD TVs. TV problems like display issues, powering-on problems, or sound issues can be fixed. Pickup and delivery fees may apply.

The cost to repair a TV will include the price of parts and labor costs, plus other associated costs. Additional charges include a trip fee for a technician to come to your home, a fee to transport your TV to and from a repair shop, and the diagnostic fee to determine what needs to be replaced.

The cost to repair a TV screen can be significantly more than the cost of purchasing a new TV. For this reason, replacing or repairing a broken TV screen is not considered feasible.

For example, the price of a new Samsung 40-inch LED TV is about $400, yet the cost of a replacement display panel for this model is about $380. This price is only for the replacement part and does not cover diagnostic costs, labor costs, or travel or shipping fees.

Unless you are trying to fix a TV from the ’80s or earlier, cracked TV screen repair is not feasible; the entire display panel must be replaced instead. The cost of a replacement TV display panel is more than the cost of buying a new TV, and that’s before labor and other service costs.

The cost of TV screen replacement is generally the same as or more than the cost of buying a new TV. Therefore, replacing a broken or malfunctioning TV screen is not considered a viable option. If the TV is under the manufacturer’s warranty, the manufacturer may replace the entire unit.

TV manufacturers do keep replacement TV screen panels on hand to support products under warranty in case the screen malfunctions, due to manufacturer defect.

If you still want to replace a damaged or malfunctioning TV screen, your best option is to find a used replacement panel or a broken TV of the same model on which the screen is still functional. You might find one on eBay, and you can hire a technician to change out the panel.

The cost of a used replacement TV panel ranges from $50 to $350 or more, excluding shipping, depending on the brand and size. Note that the chances of finding exactly the part you need in excellent condition are slim, and the cost excludes the cost of installation by a repair shop.

Whether your TV is LCD, LED, plasma screen, or 4K (Ultra HD), the cost to fix common problems ranges from $60 to $350, depending on the repair type and the brand of TV being repaired.

These repair problems could have more than one possible source, so a technician should take time to narrow down the exact problem. TVs are repaired by replacing faulty components.

TV motherboard replacement costs between $200 and $350, including parts and labor, or about $275 on average. Motherboard replacement parts range from $35 to $199and labor costs from $60 to $125.

A TV inverter repair costs $104 to $171, including parts and labor, with an average cost of $138 for a TV with one inverter board or $178 for two. Parts range from $7 to $74, and the average labor cost for TV inverter repair is $97 per hour.

The function of an inverter board in a TV is to power the backlight of the screen. The inverter board requires a few hundred volts of power. If the inverter board goes bad, this would cause the TV to power on and have sound but no picture.

When an inverter component goes bad, it is usually replaced rather than repaired. In some cases, the capacitors on a converter board fail, and a technician can fix it by replacing the capacitors rather than replacing the entire inverter component. However, if an entire inverter board replacement is not available for the model of TV being repaired, replacing the capacitors may be the only option for TV inverter repair.

A flat-screen TV bulb replacement costs between $60 to $115, with most homeowners spending $84 for parts and labor. The price for replacement bulbs ranges from $18.50 to $80.

If an older model LCD TV or projection TV powers on and has sound but no picture, this may be due to lamp burnout, which is both common and expected. In this case, replacing the bulb will fix the problem. An experienced technician should be able to replace the bulb quickly and easily.

TV backlight repair costs $100 to $122, including replacement parts and labor, at a repair shop. In-house repair costs are more due to trip fees. The price of backlight replacement parts averages around $2.50for each LED and between $20 and $25 for each CCFL strip.

If the CCFL strips for your TV are no longer available, a technician can convert the backlight from CCFL to LED using the same number of backlighting strips. Each strip of LEDs costs between $12 and $30.

A new inverter may be needed to power the LEDs, costing between $7 and $74before labor, or an average of $40. In some cases, a repair shop can convert a CCFL backlight to LED without installing a new inverter.

Backlight failure in a TV may also be due to failure of the power inverter that supplies power to the backlight. In rare cases, both the inverter and the lighting components fail.

Repairing a TV power supply board costs $23 to $234 for parts alone. Completely replacing the power supply board costs $250 for parts and labor. If one capacitor has failed, the cost for replacement capacitors is low. However, it’s more cost-effective for the technician to replace the entire board rather than spend time trying to diagnose and replace faulty capacitors one by one.

The cost to fix an HDMI port on a TV is $93 to $302. In some cases, the input circuit board that the HDMI port connects to may be damaged and need to be replaced. The cost for replacing this input circuit board, including labor, ranges from $200 to $350.

TV capacitor repair costs $60 to $129, including parts and labor. The cost for the replacement part ranges from $0.06 to $14, with the labor portion ranging from $60 to $125 per hour. TV capacitors protect the circuit from getting too much power, filter signals, and facilitate changing channels.

It is not possible to fix a TV capacitor when it fails; it needs replacing. If your TV stops working while you are using it and you notice a smell similar to ammonia or bleach, this is a sign that a capacitor has blown. However, some capacitors do not make any noticeable smell when they blow.

Flat screen replacement glass is not available. The only option for flat-screen TV glass repair is to try optical glass glue, which costs $1.70 for a 5-ml. tube. This may be an option for TV glass repair if the crack is only a few inches or less. TV panels are built as one unit at the factory, with the glass adhered to the display panel.

In-home CRT repair ranges from $199 to $249. The cost of repairing a CRT picture tube ranges from $199 for a TV that is 27 inches or smaller to $249 for a TV that is 28 inches or larger.

Picture tubes, or cathode-ray tubes (CRTs), were used in old TVs, which had much poorer image quality than modern TVs and were much bulkier and heavier.

A TV fuse repair costs between $61 and $136, with most spending $99 on average. The cost of the replacement fuse itself is $1.50 to $11, while labor ranges from $60 to $125 per hour. Additional fees may apply.

LCD flat-panel repair is not considered cost-effective. If the glass is cracked or the display is physically damaged, it is cheaper to replace the entire TV than to repair or replace the display panel.

Estimating TV repairs costs by brand is not something TV repair shops offer, however, there are general prices by type. When looking for specific repair costs for your TV, you’ll find them in the common repairs price list above. Pricing applies to brands such as Samsung, LG, Sanyo, TCL, Insignia, HiSense, Sony, Toshiba, Pioneer, and Vizio.

More popular TVs are usually less expensive to repair because repair shops order replacement parts for them in bulk, which allows them to buy those parts at a lower cost.

The cost of flat-screen TV repair ranges from $42 to $359. You cannot fix a broken screen, but the price of a new flat-panel TV starts from around $249 for a 1080-mp (non-4K) LED TV from LG to as much as $14,999 for an 85-inch 8K LED TV from Samsung. A TV referred to as a “flat TV” or “flat-screen” TV might be any of the following:

LCD TV repair typically costs $60 to $85 for diagnostics testing, and $200 to $300 to perform repairs. LCD TVs use backlighting, which may fail. Newer LCD TVs use LED strips for backlighting. Older ones might use CCFL. If CCFL backlighting fails, a technician can replace it with LED backlighting.

An LED TV is just an LCD TV that uses LED backlighting, which all newer models do (older models use CCFL backlighting). The cost to replace one LED backlighting strip ranges from $100 to $122, including parts and labor.

The cost to replace the motherboard, inverter, or LED"s in a 4K TV ranges from $100 to $275 or more depending on the brand and model. The cost for screen repair for a 4K TV is irrelevant because it cannot be fixed or replaced at a cost that is lower than the cost of a new 4K TV.

Digital light processing (DLP) TVs are also known as projection TVs. DLP big screens have not been made since 2012, and DLP TV repair is usually not worth the cost except for a lamp burnout, in which the bulb can be replaced. The cost to replace bulbs ranges from $60 to $115.

TV repair shops charge an average $60 to $125 per hour, or a flat rate of $50 to $250, which includes the diagnostic fee. Additional costs after that depend on the repairs needed and the brand and type of TV. However, most stores will have a minimum charge of about $90.

The brand and model of your TV will dictate the final repair cost, with more expensive brands and larger TVs costing more to repair. Consider the remaining lifespan of the TV before paying for repairs. You can now buy bigger TVs with more features and better displays for a TV that won’t need repairs for a while and probably comes with a warranty.

The cost of labor to fix a TV ranges from $60 to $125 per hour, or a flat rate of $90 to $299. If the work is performed in your home, the cost ranges from $25 to $125 per hour plus the trip fee. Most TV repairs take 1 to 3 hours if the repair specialist has the parts already.

Some shops will pick up and deliver a TV for free. Others charge a fee that ranges from $40 to $75 for pickup and drop-off, with an average cost of $58.

If you live in a remote area, you may need to ship your TV to a repair facility, costing $99 to $175. Be sure to choose a delivery service that allows you to track the shipment and confirm delivery. When sending your TV into a service center for repair, you will be contacted regarding the associated costs and asked to process payment before the repair is completed, which usually takes two weeks including the shipping time.

Many TV repair shops charge a diagnostic fee that ranges from $20 to $60, depending on whether it is done in your home or the repair shop. Some shops charge a flat fee that ranges from $50 to $250that covers both the diagnostic cost and labor cost. In many cases, the initial diagnostic fee will be applied to the repair cost if you have the shop do the repair.

The more expensive a TV is, the more sense it makes to purchase an additional warranty to defray the potential for costly repairs. Best Buy offers an $89 five-year extended warranty for entry-level TVs. On larger TVs such as the 85-inch Samsung QLED 8K TV, which costs $14,998, the five-year warranty from Geek Squad costs an additional $1,699—11.33% of the cost of the TV.

With modern TVs, repair entails component replacement or replacement of capacitors, for which high levels of certification are not necessary. Generally, TV repair shops will let you know if their employees have certification.

First, check that the connecting cable is securely in the socket on both ends. If that doesn’t work, try substituting another data cable if you have one, or test it with a replacement cable.

Satellite dish repair is either covered by your satellite service company or the cost for a technician to fix it ranges from $80 to $150. Repairs may also be billed at an hourly rate of $50 to $65.

The cost of mounting a TV ranges from $149 to $199, with most people paying around $174 for the labor. The mounting hardware costs between $20 and $500 depending on the brand of mounting hardware and the size of your TV.

There are various ways you might be able to save money on TV repair. These include transporting your TV to a repair shop, using a shop that charges in 15- or 30-minute increments, diagnosing the problem yourself, using salvaged parts, and doing the repair work on your own.

You can also consider the cost of TV repair when purchasing a new TV. More popular TV models are less expensive to repair because repair shops buy parts for the most common TVs in bulk and are therefore able to get them at lower prices.

Plug - If the TV is not powering on and no status LEDs are lighting up, start by plugging the TV into a different outlet. If the TV is too challenging to move, you can run an extension cord from another nearby outlet.

Circuit breaker - Check the circuit breaker for the power outlet that the TV plugs into. You can check the breakers by opening the door to your breaker panel and looking for circuit breakers that are in the OFF position.

Power cable - Check the power cable. If it is a removable cable, you can test it by substituting a power cable from another piece of equipment in your home, or you can buy a replacement cable for this test. The cost for a replacement TV power cable ranges from $2.50 to $10.

Remote control - If the TV is not powering on with the remote control, you should try replacing the batteries. For remote controls with a status LED light, there could be enough power to light the LED but not enough power to send a signal to your TV.

Inverter is bad -It is possible that the inverter, which powers the backlights, has gone bad and needs to be replaced. It’s also possible that one or more capacitors on the inverter have gone bad, in which case a technician may be able to replace capacitors more cheaply than replacing the entire inverter.

Lamp burnout -In a projection TV or older LCD TV, no picture may be caused by lamp burnout. In this case, a technician can replace the bulb quickly and easily.

Plug headphones into the headphone jack. If sound comes from the headphones plugged into the headphone jack, this indicates a problem with the TV speakers.

The primary way to save money on TV repair would be to perform the work yourself. This may require you to purchase and get familiar with various tools such as soldering tools, and methods for replacing a capacitor or some other component.

The right parts - It can be complicated to determine which component of a TV is failing and causing the TV not to work correctly. If you buy a replacement part and perform the repair yourself, the TV may still not work, either because you replaced the wrong part, the part was old and not working properly to begin with, or you did not perform the work correctly. Buying multiple replacement parts can become costly.

Lack of experience – you might cause more damage to the TV due to your lack of knowledge and experience, and you might also end up causing a fire with your soldering iron or being electrocuted.

The cost of repairing a TV could be as much as $500 if multiple repairs are needed. Consumer Reports recommends not to spend more than 50% of the cost of a new TV repairing the old one.

If you have a newer TV that cost thousands of dollars, having it repaired would most likely be cost-effective. If the TV only cost a few hundred dollars to begin with, replacing the TV is more likely to be the best option.

Not included in these prices from Best Buy are 1080P screens, which range from $249 to $279 for 43-inch TVs from brands like Samsung, Sony, and LG. On the upper end, Sony and Samsung both have 95-inch 8K LED TVs for $69,999.

In most cases, a flat-screen TV can be fixed. The exception is a physically damaged display panel or screen. Most other issues including failing speakers, backlights, or power supply. Burned out fuses and damaged input ports can also be repaired.

You cannot replace a broken flat-screen display. New TVs costs anywhere from $249 for a 1080P (non 4K) LED TV from LG to as much as $14,999 for an 85” 8K LED TV from Samsung.

Some shops will pick up and deliver a TV for free. Others charge a fee that ranges from $40 to $75 for pickup and drop-off, with an average cost of $58.

If you live in a remote area, you may need to ship your TV to a repair facility, costing $99 to $175. Be sure to choose a delivery service that allows you to track the shipment and confirm delivery.

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.

The origins and the complex history of liquid-crystal displays from the perspective of an insider during the early days were described by Joseph A. Castellano in Liquid Gold: The Story of Liquid Crystal Displays and the Creation of an Industry.IEEE History Center.Peter J. Wild, can be found at the Engineering and Technology History Wiki.

In 1888,Friedrich Reinitzer (1858–1927) discovered the liquid crystalline nature of cholesterol extracted from carrots (that is, two melting points and generation of colors) and published his findings at a meeting of the Vienna Chemical Society on May 3, 1888 (F. Reinitzer: Beiträge zur Kenntniss des Cholesterins, Monatshefte für Chemie (Wien) 9, 421–441 (1888)).Otto Lehmann published his work "Flüssige Kristalle" (Liquid Crystals). In 1911, Charles Mauguin first experimented with liquid crystals confined between plates in thin layers.

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.

The MOSFET (metal-oxide-semiconductor field-effect transistor) was invented by Mohamed M. Atalla and Dawon Kahng at Bell Labs in 1959, and presented in 1960.Paul K. Weimer at RCA developed the thin-film transistor (TFT) in 1962.

In 1964, George H. Heilmeier, then working at the RCA laboratories on the effect discovered by Williams achieved the switching of colors by field-induced realignment of dichroic dyes in a homeotropically oriented liquid crystal. Practical problems with this new electro-optical effect made Heilmeier continue to work on scattering effects in liquid crystals and finally the achievement of the first operational liquid-crystal display based on what he called the George H. Heilmeier was inducted in the National Inventors Hall of FameIEEE Milestone.

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.

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.

A comparison between a blank passive-matrix display (top) and a blank active-matrix display (bottom). A passive-matrix display can be identified when the blank background is more grey in appearance than the crisper active-matrix display, fog appears on all edges of the screen, and while pictures appear to be fading on the screen.

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 s