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How to Repair a Broken LCD TV Screen
How to Repair a Broken LCD TV Screen
By Fatima Rangwala
So it's hardly just been two or three years for your LCD screen to serve you with all the entertainment and one fine day, what you see is, you have a big dent in the screen, probably due to some obvious reasons or perhaps some internal technical reasons. Whatever be the reason, the bottom line is- you have a broken LCD TV screen and you are on a high to either learn to fix it or replace it entirely. The broken LCD screen problems can not only arouse in television sets but laptops are also prone to such issues. Many people have this tendency of repairing a particular piece of electronic item rather than going for its overall replacement. While many others believe that if the repairing cost is tossing out to be more than the cost of the whole replacement set, it's better to purchase a brand new LCD screen and fix it to the old unit. Well, this thought isn't bad either! But there are two most important points one has to look out while going for the replacement procedure and they are: firstly, see that the screen hasn't extended its warranty period. And secondly, the consumer needs to find a reliable seller or manufacture if he/she wants to buy the LCD screen in a good price. Later on, they might also have to find reliable service men who can fix the new screen and do the overall job correctly. The cost carried for the same is different. So, although replacement sounds like a good option, it is bit lengthy and fallible. It is advisable that one should go for the broken LCD screen replacement procedure only when there are a chain of problems in the whole working unit and not just one or two.
Usually an LCD TV screen has a good life expectancy up to 10 years. Moreover, the value of the monitor/screen increases with the resolution, size and clarity of the panel installed in the screen. So, if there is any sort of malfunction or damage done to the screen, the cost of its repairs comes with a price too! Fortunately, half your cost of paying the service men would be saved because with some lucid steps explained on how to repair a broken LCD screen given below, all you have to think of spending your money on, is, to buy a replacement screen and do the rest of the job all by yourself.
Signs of a Broken LCD TV Screen
Well, under this subject the most common problem why an LCD TV screen fails is the dimming of the back-light after a significant use. However, there are other obvious signs like, the system starts off but the screen is blank. May be there's an issue with the panel whose job is to display a picture. Also, the problem of blank screen appearing can be due to the panel not receiving good amount of data or power from the source. The full form of LCD is liquid crystal display which is made of two glass layers wherein, the outer layer is constructed to protect the inner layer. So if there is an ugly crack on the outside layer of the screen, fixing the same is an easy job. No specific glass is required nor any special tools are needed. All that is required is for you to look down 'coz now it's time to read the procedure for replacement..
How to Fix a Broken LCD TV Screen
For now all you need is a small screwdriver and of course a replacement LCD TV screen to replace it to your old unit.
Step 1: In this first step of repairing the broken screen, it's important to turn off the TV, unplug the power supply and place it face down on a working table carefully.
Step 2: Using the screwdriver unscrew all the fasteners from the television and also detach the back panel from the unit. This will give you a clear look at the motherboard situated at the center of the TV behind the screen.
Step 3: Also what else you would see is an inverter board mounted at the side end of the motherboard. Remove all the inverter screws and expose the whole unit. There will be a bunch of cables connected to various ports. They transmit electrical power to the LCD screen.
Step 4: Your first job to do is, check for all the connections of the inverter board to see whether they are properly secured or not. If they aren't, unplug the cables and try plugging them back into the ports. Power the screen and see if its working, if not, then go ahead.
Step 5: Remove all the fasteners, plugs and connections from the ports in the board and pull out the whole board from the TV set and keep it aside.
Step 6: Now replace the old for a new board. Fit the new replacement board in the television, and hopefully you have marked the positions of the cable connections. Join the cables together and attach all the screws back in place. Lastly, replace the back cover of the inverter and also the rear panel of the television carefully.
No matter with how much care and precaution you handle your electronic devices, if accidents have to happen, they will! And when they do, don't fear or panic, just remember to read this article (if in case again) and you have your solution in hand!
LCD TV Recommended Dealers
LCD TV Recommended Dealers
By Robert Wiley, Senior Editor
To the right is a list of authorized online Internet Dealers which sell LCD TVs and LED backlit LCD TVs. These online retailers normally have excellent selection as well as solid after purchase service – offering you a great combination of attributes when purchasing an expensive flat panel TV. We recommend these retailers based on their service track record, authorized status, prices, and stock inventory.
LCD and LED LCD Televisions are usually large and require a certain amount of care when handling. These retailers have lots of history with thousands of types of TV units shipped, so they know how to safely handle the product during shipping. Due to this, they also know how to get the product to you faster through their shipping network. These dealers also have more inventory and will not tell a customer they have the product in stock when they do not or attempt bait-and-switch techniques by advertising an extemely low price on a product that is out of stock or hasn;t been released. All online order systems are secure and with the exception of Amazon, they all have an easily accessible toll free number to call to speak to a customer representative.
A few other helpful tips when buying a television from an Internet Retailer that you are not sure is authorized.
CHECK THEM OUT
First you might consider going to the web site of the manufacturer and checking to see if they have a listing of all the authorized Internet dealers. That way, you can see if the company in question is authorized.
POLICIES
Make sure you can access the policies on the dealer web site with regard to returns and every other aspect of the transaction. Read them. What is covered, what is not? If you decide to order from them, print out a copy of the policies as they can change without notice.
TECH SUPPORT
Through the toll-free provided, ask the company representative you speak with some specific questions about the product before ordering. Make sure they can give you some post-purchase technical assistance and guide you in the purchase of accessories such as mounts, cables, etc.
ADVICE AND PRICE
Look for knowledgeable, unbiased advice on which products may best suit your needs.
Generally, you are looking for a well established, specialized dealer who will give you a good price AND good service and support. The better the e-tailer knows its products, the smoother the ordering process will be. It is possible to buy an LCD TV online, and save a lot of money in the process! You will definitely find the best prices online, and there is also good customer service to be found from online dealers. Using these steps, you should be able to avoid a bad online ordering experience.
Step 7: Buy an LCD TV or LCD LED Flat Screen TV
Step 7: Buy an LCD TV or LCD LED Flat Screen TV
By Robert Wiley, Senior Editor from LCD TV buying guide
BRICK AND MORTAR BIG BOX
If you go with a traditional, "brick and mortar" retailer, remember to shop around-not just for the best prices but also for the best LCD or LCD LED TV flat screens. While established big box retailers such as Best Buy, Frys, HHGregg, are almost always authorized dealers of what they sell they also enjoy the benefit of immediate purchase gratification and make it easier to return the product if necessary. They usually have a vested interested in pushing certain brands or outdated models to reduce inventory and benefit from special rebates the manufacturers offer them, so be careful with this and know what you want to purchase ahead of time. Big box retailers typically will not have as good of pricing as you will find online. They also charge outrageously exorbitant prices on the extended warranties and accessory products - thus making up for small margins on the TV. Sometimes big box retailers will have slightly better pricing through their online portals.
ONLINE RETAIL
Online dealers such as Amazon, Vanns, and One Call, and Crutchfield often have excellent pricing and free shipping on TVs and are also authorized for all the products they sell. They have great inventory of LCD TVs and LCD LED Televisions and do not have the luxury of trying to steer you to the product that they want you to buy. Being able to order online offers maximum convenience though not immediate gratification. Their accessory products may be priced somewhat more reasonably than big box retailers. We recommend purchasing from online dealers that are authorized for the products they sell. This often means the larger more esablished online retailers as most small etailers are not authorized. Purchasing from online dealers that are not authorized by the manufacturers can lead to headaches such as poor return policies, excessive restocking charges, and poor post purchase service (not to mention b-stock or gray market goods). The trust factor is important as trying to read through policies can be onerous. The dealers we recommend on this site are the larger authorized online dealers.
Lastly consider shopping for your extended warranty online no matter where you purchase the television. Most extended warranties are created equal as long as they cover in home service and parts and labor. Shopping online for the extended warranty can save you hundreds of dollars.
8 STEPS TO BUYING AN LCD TV
Step 1: What exactly is LCD TV?
Step 2: How do LCD Televisions work?
Step 5: Installation Considerations
Step 6: View the Top 10 LCD Televisions
Step 7: How and Where to buy a LCD TV
Step 8: Find reputable online LCD Televisions Dealers
Step 6: Top LCD and LED LCD TVs; Top 10 Best Selling, Top 10 by Price, Top Recommended by Size
Step 6: Top LCD and LED LCD TVs;
Top 10 Best Selling, Top 10 by Price, Top Recommended by Size
By Robert Wiley, Senior Editor
Choose an LCD or LED backlit LCD TV
What follows is a list of the current best selling LCD and LED backlit LCD Televisions by popularity from retailers and etailers in North America. The list is comprised of the top selling TVs. In the event none of these LCD or LED LCD TVs is in the size category you are looking for we have included below our Recommended by Size TV chart where you may see the recommendations from our editors for all TVs within a certain size. Lastly, we have included on this page LCD and LED LCD TVs that we consider well priced or discounted to appealingly low prices. We hope that from this selection, you will find the perfect TV for your particular situation.
8 STEPS TO BUYING AN LCD TV
Step 1: What exactly is LCD TV?
Step 2: How do LCD Televisions work?
Step 5: Installation Considerations
Step 6: View the Top 10 LCD Televisions
Step 7: How and Where to buy a LCD TV
Step 8: Find reputable online LCD Televisions Dealers
Step 5: Installation Considerations for LCD and LCD LED Flat Screen Televisions
Step 5: Installation Considerations for LCD and LCD LED Flat Screen Televisions
By Robert Wiley, Senior Editor
Determine how you're going to install your or LED LCD Flat Screen TV.
LCD technology affords consumers new options when it comes to the physical placement of their TV displays. Gone are the days when you had to configure a room around the television set. Now, you can incorporate the TV into almost any décor, if you give a little thought to the matter beforehand. There are half a dozen ways to install your new LCD TV, which virtually ensures that you'll find the right way to fit one in your home.
You can mount your flat-panel display on almost any wall in your home.
- Flat Wall Mounts allow you to maximize the space-saving benefits of plasma technology. This option is generally the least expensive, and it adds just under two inches to the monitor's total depth.
- Tilt Wall Mounts enable you to place your TV above eye level, keeping it out of the way though readily viewable from anywhere in the room. This mounting option is typically used to install LCD monitors above fireplaces and in bedrooms. The tilt wall mount adds from 4 to 6 inches to the depth of the mounted display.
- Table Stands are another popular way to display LCD units. Realize, though, that these units are not one-size-fits-all appliances. Each display has its own custom-fitted table stand. Oftentimes one is included with the monitor itself; occasionally, though, you will have to purchase the stand separately.
- Articulating Wall Mounts make use of swivel arms to render the LCD unit flush with the wall-and out of the way-when not in use. Pulled out, this mounting device allows you to turn the display 120° to either side and as much as 10° up or down.
- Ceiling Mounts enable you to mount your TV where you want it-in the event that a wall isn't handy. This option is generally coupled with a tilt mount, so that the display can be adjusted downward for easier viewing. Lengths of ceiling mount poles vary according to customer needs, though the standard lengths are from 24 to 43 inches.
- Lifts There are a variety of lift options also available such as motorized ceiling lifts, console lifts, motorized furniture lifts and hydrolic furniture lifts. Lift options allow the plasma or LCD TV to be hidden from view when not in use. Hydrolic lifts are manually operated and less expensive while motorized lifts can be operated using remote control.
8 STEPS TO BUYING AN LCD TV
Step 1: What exactly is LCD TV?
Step 2: How do LCD Televisions work?
Step 5: Installation Considerations
Step 6: View the Top 10 LCD Televisions
Step 7: How and Where to buy a LCD TV
Step 8: Find reputable online LCD Televisions Dealers
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Step 4: Flat Screen LCD and LED LCD TV screen size considerations; Which size is right for you?
Step 4: Flat Screen LCD and LED LCD TV screen size considerations; Which size is right for you?
By Robert Wiley, Senior Editor
Determine the right screen size based on your budget and your floor plan.
In the past, flat screen LCD TVs were more common in smaller sizes (27" and less) and LED backlit LCD TVs were produced in the largest sizes. One reason was that quality-control issues limited display size: Increasing the size of an LCD panel meant adding pixels and three transistors for each additional pixel. It also made distributing the light evenly more difficult, which, in turn, interfered with color reproduction. This is why colors sometimes appeared slightly off or faded in larger LCD TVs. Modern production techniques and LED backlighting technology have eliminated this problem in current large LCD screens.
Now factories in Japan and Korea can mass-produce the super sized sheets of glass embedded with transistors that are necessary to achieve large-scale LCDs. All of which means you'll be seeing larger flat-screen LCD displays with increasingly smaller price tags. LCD prices have been falling rapidly lately, nearly inline with plasma but with screens 50 inches and larger you will still find the most value for the dollar in a plasma television. So, if you're choosing purely based on flat-panel display size, Plasma is still the better choice but in another year or two prices may equalize between the two technologies or LCD panels may even be less expensive.
To get the most out of your investment, remember what your mother always said about sitting too close to the TV-that it's no good for you. Well, she might have been thinking about your health, but we're thinking about your viewing pleasure. For the optimal viewing experience, you need to maintain the right distance between your viewing area and your television screen.
Note: Some audio-visual critics have observed that fixed-pixel displays tend to show their pixel structures at closer viewing distances, so one might notice a sandy texture to the screen when the set is viewed too close. This underscores the importance of maintaining an appropriate viewing distance between you and your LCD or LED TV when configuring your viewing area.
The right distance depends on the size of your Flat Sreen LCD or LED LCD:
- For 20 to 27-inch displays, you should be able to watch comfortably from 2.5 to 5 feet away.
- For 32 to 37-inch TVs, you should sit back 6 to 8 feet from the screen itself.
- For 42 to 46-inch TVs, you'll need 10 to 13 feet between you and the screen.
- 50-inch LCD or LED TVs displays look best when viewed from 12 to 16 feet away.
- 60-inch LED LCD TVs are best viewed from 14 to 16 or more.
- 70-inch LED LCD TVs. You should sit 16 to 20 feet or more from the TV.
Get the lowdown on HDTV compatibility.
If you're one of the 55+ million households sitting astride cable systems that can carry HDTV signals, your LCD or LED LCD TV will enable you to take advantage of the better picture you can get from a higher resolution unit displaying digital HDTV broadcasts. Most LCD Televisions come with built-in ATSC tuners, which enable them to pick up over-air HD broadcasts using antennas. In addition, manufacturers have begun packaging ATSC and cable tuners in LCD TV sets, making them optimal for watching digital HDTV-on local as well as national broadcasts.
8 STEPS TO BUYING AN LCD TV
Step 1: What exactly is LCD TV?
Step 2: How do LCD Televisions work?
Step 3: What are the advantages of LCD Televisions?
Step 4: What do you need to consider before you buy your LCD TV?
Step 5: Installation Considerations
Step 6: View the Top 10 LCD Televisions
Step 7: How and Where to buy a LCD TV
Step 8: Find reputable online LCD Televisions Dealers
Step 3: Flat Screen LCD TV; Advantages for LCD and LED LCD Flat Screen Televisions
Step 3: Flat Screen LCD TV; Advantages for LCD and LED LCD Flat Screen Televisions
by Robert Wiley, Senior Editor
Brighter with Higher Contrast
It's easier to watch. Flat screen TVs like LCDs, LED LCDs and Plasmas are significantly brighter and feature higher contrasts than traditional CRT sets. Which means that an LCD TV will perform exceedingly well under most ambient light conditions. With LCD TV viewing a brightly lit room won't wash out its picture, nor will lamplight cause a glare on your television screen. The beauty of these flat screens is that you don't have to turn out the lights to see the image clearly and easily. Nor do you have to worry about eyestrain, since neither LCDs nor Plasmas flicker the way old-fashioned TVs do.
Recently, LCD TVs (also dubbed LED TVs) have made great technological advancements with the new LED backlighting system. This enables better black levels and a brighter more energy efficient TV performance.
Viewing Angles and Dot Pitch
And, you can watch TV from almost anywhere in a room since flat-screen LCD television displays can have up to a 160° viewing angle, which means your TV will look good when viewed from any point 80° in either direction from the center of the display.
One issue affecting the overall quality of the picture reproduced on LCD and LED LCD TVs has to do with dot pitch. This term refers to the distance between subpixels of the same color in adjoining pixel triads. The closer these "dots" are to one another, the sharper the resolution will be. This is especially true when displaying computer signal images and graphs. And the picture in front of you will be more realistic and detailed. Higher dot pitches also increase the viewing angles of LCD panels. Since dot pitch is measure in millimeters (mm), a good rule of thumb is this: Smaller dot pitches make for sharper images. You generally want a dot pitch of .28mm [" 10,000 pixels/in2 of your display] or finer.
Note: Plasma TV displays have long been touted as having wider viewing angles than comparably sized LCD TVs. But recent improvements in quality have made LCD televisions (especially those with LED backlighting have made them nearly comparable to Plasma TVs with respect to their viewing angles. According to Sharp, a leading manufacturer of LCDs, the newest generation of LCD displays have just as good viewing angles as plasma sets, but this is only true of the better brands. In any event, even the best LCD monitors have yet to achieve the breadth of viewing angles found on typical Plasma monitors.
Smooth Bold Picture Quality
The picture is smooth, colorful, and (best of all) wide. LCD and LED Flat Screen TVs have none of those annoying scan lines that conventional sets do. This owes to the fact that each subpixel has its own transistor electrode, which creates smooth, evenly lit images across the entire surface of the display. It also enables these displays to reproduce images that are saturated with color. [256 shades of red x 256 shades of green x 256 shades of blue " 16.8 million different colors!]
Recent advances in LCD technology have markedly increased the response time of these displays, resulting in even smoother on-screen presentations. There have also been recent increases in the refresh rate as one of the latest advancements to 120Hz and 240Hz and a manipulated 240Hz to form 480Hz. These frame rate increases help get rid of motion blur for fast action scenes. For more on this topic see our article titled 120Hz, 240Hz What does it mean? One way to think about response time is in terms of the amount of time it takes a pixel to "refresh" itself-i.e., to go from being active to being inactive, which is to say, ready to be re-activated). Response time is measured in milliseconds (ms), with the best LCD monitors now clocking in with response times under 20ms. Slower response times (>20ms) can cause the image on the panel to lag and appear jerky, an effect known as "streaking" or "trailing." Another phenomenon associated with slower response times is "ghosting." This occurs when the display is made to switch quickly from light to dark states (or vice-versa). In these instances, on-screen images may appear to stay on the screen belatedly.
LCD displays come either with a 16:9 aspect ratio (i.e., 16 units wide to 9 units high), the proper one for viewing HDTV and for watching DVDs, or with a 4:3 aspect ratio, the norm for most broadcast television shows. If you opt to go with a widescreen (16:9) display, does this mean that you'll have to watch some shows where the image is distorted or stretched unnaturally? No. When displaying a "normal" or 4:3 picture image from satellite, VCR, or cable TV, the image can be viewed in a number of ways-in its original format (with black or gray bars on the sides of the screen), or in "full" mode (where the image is converted or "stretched" using specially designed algorithms to reduce the visible stretch marks as much as possible). Again, the quality of the picture produced under such circumstances depends largely on the quality of the television with which you scale-up 4:3 pictures or scale-down 16:9 ones. Nevertheless, this is only a temporary dilemma: Since HDTV is shown in widescreen, this is the format of the future for much of broadcast television.
The display is multi-functional and long-lived. An LCD is a television monitor, capable of displaying HDTV, regular TV, and home video. It's also a computer monitor. In fact, it can accept any video format. LCD TVs typically include inputs for (a) HDMI, (b) S-video and component video, and (c) one or more RGB 15 pin computer input, USB, and other inputs from a computer. Because of the high resolution of LCDs, text and graphics look especially sharp when viewed on them, which makes them the best solution for displaying data and web-based content.
You can expect to use your LCD TV in many capacities for many years: The average lifespan of one of these displays is 60,000 hours. If watching TV was your full-time job, and you did it 24 hours a day, it would take you almost 7 years to wear out your LCD display. With more normal viewing habits of, say, 8 hours per day, you can extend the lifespan of your TV by a decade or more (to about 20 years)!
A more immediate concern is the actual lifespan of the light source in your LCD or LCD LED Flat Screen Television. This is perhaps THE critical component of your display unit. It is particularly important for maintaining a proper white balance on your TV. As these florescent bulbs age, colors can become unbalanced, which could result in too much red, for example, in your picture. So, it pays to buy name-brand displays. You will definitely pay more for better LCD display brands like Sharp, Toshiba, JVC, or Sony than you will for cheap Chinese or Korean variety knock-offs, but you'll get a backlighting bulb of higher quality and, in the end, a TV whose colors will stay truer longer.
In some cases, the warranty for this particular feature can be shorter than for the display as a whole. This means you might have to buy a new LCD TV because the coverage on its backlight has expired. Moreover, some bulbs can be replaced, while others are built in to the unit itself. You should definitely do some research on the backlighting system, how it's configured, and how it's warranted.
8 STEPS TO BUYING AN LCD TV
Step 1: What exactly is LCD TV?
Step 2: How do LCD Televisions work?
Step 3: What are the advantages of LCD Televisions?
Step 4: What do you need to consider before you buy your LCD TV?
Step 5: Installation Considerations
Step 6: View the Top 10 LCD Televisions
Step 7: How and Where to buy a LCD TV
Step 8: Find reputable online LCD Televisions Dealers
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Step 2 : How do LCD and LED LCD TVs work
Step 2 : How do LCD
and LED LCD TVs work
By Robert Wiley, Senior Editor
How does a LCD (Liquid Crystal Diode) TV operate?
The Basics: LCD TVs and so-called LED TVs work by blocking light. By sandwiching a solution of TN liquid crystals between two perpendicularly aligned panes of polarized glass, it becomes possible to manipulate the intensity of light as it passes through this crystalline matrix and out the glass panel at the other end. Depending on the voltage of the electrical charge running through them, liquid crystals will untwist so that the intensity of light able to pass through the second polarized pane is affected. Basically, these displays can switch between light states (where the liquid crystals are fully twisted) and dark states (where the liquid crystals are fully untwisted), or somewhere along the gray scale in between. The term "liquid" in liquid cyrstals is actually a misnomer as they are not a fluid substance but rather a hard crystal.
Addressing: A liquid crystal display consists of an array of tiny segments-called "pixels"-that are manipulated to form images or to present information. Addressing is the process by which pixels are turned on (which disables the passage of light) and off (which enables the passage of light) so as to create an image on the polarized display pane in front of you. So-called active-matrix LCD TVs employ thin film transistors (TFTs), or tiny switching transistors and capacitors arranged in a matrix on a glass substrate, to direct electric charges down columns to reach a particular pixel. This, in turn, causes the liquid crystals to untwist and "display" a predetermined amount of light generated by the light source-usually a florescent bulb-in back of them.
Color (Re) Production: The light source in an active-matrix LCD TV is a series of florescent bulbs (called CFL or CCFL), or the more newly implemented LED (light emitting diode) backlighting (LED TVs) both of which emits white light through a polarized glass pane behind the liquid crystal solution. Theoretically, then, you can start with a white display: This is one where its liquid crystals are completely twisted and therefore able to direct the full spectrum of light out through the polarized display screen in front of you. Since all wavelengths can pass through, the full spectrum of light can be manipulated to create the desired color. To achieve a full color pallet on your LCD or LED LCD TV, each pixel is divided into three subpixels-red, green, and blue-that work in conjunction to determine the LCD pixel's overall hue. These subpixels are created by subtracting certain wavelengths, and the color(s) corresponding thereto, using special filters. By exploiting a combination of red, green, and blue subpixels of various intensities (or gray scales), a single pixel triad can reproduce approximately 16.8 million colors. Recently, Sharp Electronics has introduced the new Quattron Quad pixel technology which introduces a 4th color pixel - yellow. This increases the number of possible colors 4 fold.
8 STEPS TO BUYING AN LCD TV
Step 1: What exactly is LCD TV?
Step 2: How do LCD Televisions work?
Step 3: What are the advantages of LCD Televisions?
Step 4: What do you need to consider before you buy your LCD TV?
Step 5: Installation Considerations
Step 6: View the Top 10 LCD Televisions
Step 7: How and Where to buy a LCD TV
Step 8: Find reputable online LCD Televisions Dealers
Step 1: What exactly is a Liquid Crystal Diode (LCD) TV?
Step 1: What exactly is a Liquid Crystal Diode (LCD) TV?
WHAT EXACTLY IS A LIQUID CRYSTAL DIODE (LCD) TV?
LCDs are all around us. Liquid crystal displays so prevalent, in fact, that most people couldn't get through their day without using one. This technology is utilized in digital clocks, microwave ovens, car dashboards, calculators, stereos, thermometers, and even some bathroom scales! The applications for liquid crystal displays are almost limitless, so it should come as no surprise that this technology has revolutionized the most basic home appliance of all-the television set.
Liquid crystal technology has given birth to those slim, cool-looking, bright displays that are popping up everywhere from bank lobbies to living rooms. But how does it work?
WHAT MAKES A CRYSTAL "LIQUID"?
The twisted nematic (TN) liquid crystal is the most common type of liquid crystal being used in display applications today (e.g., LCD televisions, LCD monitors, and LCD projectors). It has a naturally twisted crystalline structure. A particular feature of this crystal is that it reacts to electric currents in predictable ways-i.e., by untwisting to varying degrees depending on the voltage of the current to which it is exposed. Hence the "liquid" part of the crystal's moniker: Rather than being an oxymoron (How can a solid also be a liquid?), the term refers to the relative pliability of the crystals themselves, which is to say, their twistability.
WHAT TYPE OF BACKLIGHTING DOES AN LCD TV HAVE?
The type of backlighting is the determining factor in what people today call LED TVs. The backlighting until recently has been traditionally CFL flourescent backlighting. But more recently the backlighting has changed to the brighter and more luminous LED (light emitting diode) technology lighting. These LCD TVs with LED backlighting are technically still LCD TVs, but some have dubbed them "LED TVs," to emphasize the LED backlights.
8 STEPS TO BUYING AN LCD TV
Step 1: What exactly is LCD TV?
Step 2: How do LCD Televisions work?
Step 3: What are the advantages of LCD Televisions?
Step 4: What do you need to consider before you buy your LCD TV?
Step 5: Installation Considerations
Step 6: View the Top 10 LCD Televisions
Step 7: How and Where to buy a LCD TV
Step 8: Find reputable online LCD Televisions Dealers
LCD Television Buying Tips
LCD Television Buying Tips
By Robert Wiley
Thinking about buying a new LCD or LED TV but find yourself puzzled by all the special terminology? Don't know the in's & out's of LCD/LED Television resolution, video inputs, LCD and all the other alphabet soup? Wondering how to translate your needs into a set of features? If you're saying "yes" to any of these questions, then this guide is for you! First click on the 8 step guide to how to buy an LCD or LED TV below, or read one of the technology comparison reviews if that is the information you need to know before getting started.
8 STEPS TO BUYING AN LCD TV
Step 1: What exactly is LCD TV?
Step 2: How do LCD Televisions work?
Step 3: What are the advantages of LCD Televisions?
Step 4: What do you need to consider before you buy your LCD TV?
Step 5: Installation Considerations
Step 6: View the Top 10 LCD Televisions
Step 7: How and Where to buy a LCD TV
Step 8: Find reputable online LCD Televisions Dealers
Credit by : LCDTV BUYINGGUIDE.com
How to set up an LCD TV
How to set up an LCD TV
By eHow Contributor
Maybe you are thinking about purchasing an LCD TV or flat screen TV but are not sure about setting it up or what to do once you get it out of the box. You do not need to hang it on the wall, you can place it on a TV stand. The choice is yours. Here are some quick tips to get your LCD TV out of the box and in your living room in no time.
Instructions
1. Carefully unpack your LCD TV from the box. Do not use a box cutter, as you may cut the
screen accidentally.
2. Set the TV on the floor and take stock of the parts, directions, cables and mounting equipment for the LCD TV including stand, hardware and the sockets.
3. Assemble and hang your wall mounting bracket. If you are not mounting the TV on the wall, skip the next two steps.
4. Hang your LCD TV according to instructions if you are using a wall mounting bracket. Have two to three people on hand as the TV is heavier than it appears. Hang by a three prong outlet handy protected by a surge suppressor to protect your investment.
5. Assemble the stand, carefully dropping the screws into the sockets one at a time and fastening it tightly. Magnetic screwdrivers work best as screws tend to land sideways in these tiny crevices. Skip the next two steps if you already mounted TV on wall.
6. Cover your TV stand to avoid scratches and make sure the LCD TV has a flat, sturdy surface to stand on.
7. Connect the cable or satellite box with HDMI cable or cables provided from cable or satellite box. Usually the input is the comp. unless you have basic cable without a box, then the input should be set to cable. If that is the case, have it automatically search for channels.
8. Test the TV setup to make sure you can view a picture and record if you have a DVR.
9. Connect any additional devices using the cables in the back and on the sides of TV.
10. Connect a TV sound bar, computer, or speakers as you wish.
HDTV
HDTV
by Edward Jay Epstein
Converting to high-definition television (HDTV), whatever its benefits to American civilization, would be possibly the most costly modernization ever undertaken voluntarily. It would far exceed the cost of building the interstate highways. Even if Americans bought the cheapest equipment available today, they would need to spend more than $300 billion just to replace their analog TVs with ones capable of receiving HDTV. Television stations also would have to spend tens of billions of dollars for new equipment. To provide the carrot for this massive conversion, the federal government has already committed itself to giving away much of the remaining frequency spectrum to television stations. The public, as its incentive for converting, will get a more elongated picture -- using a 16:9 instead of 12:9 ratio of width to height -- that provides better resolution in newscasts, game shows, reality-based voyeurism, soap operas, wrestling matches and other entertainments. The public's gain has been difficult to fully assess because very few people have ever actually seen regular HDTV broadcasts.
Indeed, until very recently, HDTV was not broadcast in a form in which most Americans could get it without an antenna complex. Television stations had little incentive for broadcasting HDTV, since very few people had the ability to receive it. So they put it on relatively obscure UHF stations as a public relations gesture. Unfortunately, according to tests done by Sinclair Broadcasting, the largest broadcaster group, indoor antennas would not work without a direct line of sight to the transmitting antennas, nor if there was any interference. Further adding to its unavailability, the cable industry, which did not participate in the spectrum giveaway and thus had no incentive to show HDTV, declared that the home cable box was incompatible with it. Similarly, the satellite narrowcasters, DirectTV and EchoStar, although digitized, had little reason to launch the new satellites necessary to carry broader-band HDTV -- at least not until a significant portion of the public had the hardware to receive these signals. It was a chicken-and-egg situation: no sets, no reason to broadcast; no broadcasts, no reason to buy a set.
Like other concerned citizens, I wanted to evaluate this new technology. But I was discouraged when a high-ranking executive at Sony told me that she had considered having the company install a giant antenna on the roof of its skyscraper in New York to get HDTV broadcasts for its showroom, but had found that the cost of providing a reliable signal was "prohibitive." If Sony, which employs 100,000 engineers and technicians, could not get a reliable HDTV of its own, what chance had I of getting one in my New York apartment?
Then, just two weeks ago, I heard through the Internet grapevine that there might be a means of getting HDTV free. My proximate source was Bill Cushman, a Houston-based writer for the video magazine The Perfect Vision, who keeps close contact with the small but resourceful community of HDTV seekers. He passed on the rumor that Time Warner was secretly transmitting HDTV on unused channels of its cable system in New York, presumably to test it out. To get it, he suggested, I merely had to discard my cable box and hook the cable into a HDTV decoder.
I immediately called Time Warner in New York. The customer representative came on the line and courteously denied the rumor that there was free HDTV on its cable. There was now only one way to find out. I bought a RCA Digital Decoder ($630), which arrived by FedEx the next morning. I then unplugged the cable from the cable box and replugged it into the "Antenna A" slot on the HDTV decoder, which was connected to my Sony HDTV- ready projector. Less than 5 minutes later, I was watching HDTV on two channels, CBS and (free) HBO. It was in the 16:9 format with Dolby digital sound (CBS had five channels, HBO only two). To fine-tune these channels, one needs the service access code for the RCA decoder. Fortunately, like many other codes, it is available on the Internet.
Then, to find out what was available over the airwaves as opposed to cable, I mounted an eight-foot UHF ChannelMaster antenna on my roof, which I plugged into the "Antenna B" slot on the RCA decoder. After getting a number of tips from the Internet -- including the useful site at www.antennaweb.org1, which draws a street map from your address showing the precise path to all obtainable digital stations -- I got WNYW, the Fox digital station. According to Internet tipsters, I might also get WTNH, the ABC digital station in New Haven, Conn., and WNJT, the PBS digital station in Trenton, N. J., under the right weather conditions. But at present I can count on only three digital stations, and not everything they broadcast is converted to HDTV. Nevertheless, the material that is broadcast in HDTV -- especially the CBS programs for which Mitsubishi paid to convert and the 16:9 formatted movies on HBO -- provide an ample opportunity to assess this new technology.
There can be no doubt that HDTV renders a picture that is vastly superior to the one on conventional television. HDTV uses roughly 500,000 color pixels; conventional television uses the equivalent of about 50,000. Consider, for example, a picture of 100,00 people at a political demonstration. On HDTV, each person could be represented by five different color pixels, which could show them with multiple color outfits and banners. Conventional television would have to use one color pixel to represent every two persons, turning them into a blur. Suddenly, it becomes possible to see individually tinted hairs on a head or weeds on a baseball diamond. This cumulatively adds up to the illusion of depth, complexity and three-dimensionality. It is, in a word, fabulous.
The price for this new diversion and deception is relatively steep. Unfortunately, smaller HDTV receivers, which cost more than $2,000 (without the decoder), will not provide the full virtual-reality illusion (unless one sits only a few inches away at the risk of one's vision). So one needs a projection HDTV receiver costing between $4,000 and $8,000, as well as a decoder (another $600 to $1,000.) Then there is the cost of getting a signal. Unless one can tap into one's local cable for HDTV, as I did, one will have to invest in some sort of rooftop antenna farm or at least a satellite dish. Of course, there is the risk that HDTV will be abandoned once television stations get full title to their digital licenses. (Stations can pack four non-HDTV digital channels in the space required for one HDTV channel.) But why not see HDTV while the opportunity nobly provided by Time Warner still exists? If, of course, you can afford it.
LCD television Basic LCD concepts
LCD television
Basic LCD concepts
LCD televisions produce a black and colored image by selectively filtering a white light. The light is typically provided by a series of cold cathode fluorescent lamps (CCFLs) at the back of the screen, although some displays use white or colored LEDs instead. Millions of individual LCD shutters, arranged in a grid, open and close to allow a metered amount of the white light through. Each shutter is paired with a colored filter to remove all but the red, green or blue (RGB) portion of the light from the original white source. Each shutter–filter pair forms a single sub-pixel. The sub-pixels are so small that when the display is viewed from even a short distance, the individual colors blend together to produce a single spot of color, a pixel. The shade of color is controlled by changing the relative intensity of the light passing through the sub-pixels.
Liquid crystals encompass a wide range of (typically) rod-shaped polymers that naturally form into thin, ordered layers, as opposed to the more random alignment of a normal liquid. Some of these, the nematic liquid crystals, also show an alignment effect between the layers. The particular direction of the alignment of a nematic liquid crystal can be set by placing it in contact with an alignment layer or director, which is essentially a material with microscopic grooves in it, on the supporting substrates. When placed on a director, the layer in contact will align itself with the grooves, and the layers above will subsequently align themselves with the layers below, the bulk material taking on the director's alignment. In the case of a Twisted Nematic (TN) LCD, this effect is utilized by using two directors arranged at right angles and placed close together with the liquid crystal between them. This forces the layers to align themselves in two directions, creating a twisted structure with each layer aligned at a slightly different angle to the ones on either side.
LCD shutters consist of a stack of three primary elements. On the bottom and top of the shutter are polarizer plates set at right angles. Normally light cannot travel through a pair of polarizers arranged in this fashion, and the display would be black. The polarizers also carry the directors to create the twisted structure aligned with the polarizers on either side. As the light flows out of the rear polarizer, it will naturally follow the liquid crystal's twist, exiting the front of the liquid crystal having been rotated through the correct angle, that allows it to pass through the front polarizer. LCDs are normally transparent in this mode of operation.
To turn a shutter off, a voltage is applied across it from front to back. The rod-shaped molecules align themselves with the electric field instead of the directors, distorting the twisted structure. The light no longer changes polarization as it flows through the liquid crystal, and can no longer pass through the front polarizer. By controlling the voltage applied across the liquid crystal, the amount of remaining twist can be selected. This allows the transparency of the shutter to be controlled. To improve switching time, the cells are placed under pressure, which increases the force to re-align themselves with the directors when the field is turned off.
Several other variations and modifications have been used in order to improve performance in certain applications. In-Plane Switching displays (IPS and S-IPS) offer wider viewing angles and better color reproduction, but are more difficult to construct and have slightly slower response times. IPS displays are used primarily for computer monitors. Vertical Alignment (VA, S-PVA and MVA) offer higher contrast ratios and good response times, but suffer from color shifting when viewed from the side. In general, all of these displays work in a similar fashion by controlling the polarization of the light source.
