lcd screen heat damage quotation

LC displays (LCD) have a well-defined isotropic or operating temperature limit, above which the actual liquid crystal molecules will lose their orientation and will assume a random orientation instead of ‘twisting’ through the light valve.

The site goes on to note that temperatures above 100°C (212°F) can permanently damage the coating on LCD displays, though Samsung claims that storing your display at temperatures above 45°C (113°F) can damage it, so it"s possible that Vartech"s 100°C threshold is specifically a property of their ruggedized displays.

Vartech also mentions that as temperatures drop the viscosity of the LC increases, resulting in slower response times (which will first manifest as "ghosting", and further as very slow image updates/transitions, like a bad PowerPoint slideshow in slow-mo). The site doesn"t make mention of whether excessively low temperatures can permanently damage a display, but the line

LCDs used in outdoor situations have many concerns to deal with in addition to any that they might normally encounter during indoor use. Initially some concerns are weather related such as moisture in the air or extreme temperatures. Another concern that is often not understood or just not known about at all is sunlight damage.

Liquid crystal displays use organic components that are susceptible to UV (<400 nm) and IR (>750 nm). These bandwidths of radiation have an observable impact on the organic components in LCDs. Extended exposure has been known to cause a color shift and a washed out look to images displayed with the LCD.

In any case it is important to protect your display from the elements, especially if it is going to be exposed to harsh environments not intended by the manufacturer. One way to do this would be to utilize a Hot Mirror with a UV blocker. This will significantly reduce the amount of IR radiation between 750 nm and 1200 nm, as well as the UV radiation below 400 nm. If the LCD is going to be used outdoors for extended periods then an extended hot mirror may be necessary, which extends the bandwidth protection out to 1600 nm and will help reduce some of the longer wavelength IR damage.

Another concern with liquid crystal displays are their susceptibility to overheating due to excess IR radiation. The LCD is intended to operate within a certain range of temperatures according to the manufacturer’s instructions and outdoor use can lead to higher than normal temperatures. The display being exposed to excessive heat can cause the crystal to become isotropic and fail to perform properly. A hot mirror can help alleviate these concerns as well by reducing the amount of infrared radiation that heats the display.

Before we get into specifics about how this would work, it is important to understand that liquid crystal display panels and polarizers utilize organic compounds that are susceptible to high heat and light energy stress. These organic compounds will eventually break down if deployed in high stress environments. One such contributing factor to LCD panel failure is the use of a high energy unfiltered illuminator. The near IR and shorter UV wavelengths not only add excess heat that may overheat the liquid crystal and prevent them from working properly, but they also add UV band energy that is destructive to organic compounds.

Over time the UV and IR will degrade and damage the LCD panel and polarizers to the point that they produce an unacceptably poor performance. In most applications this is observed to be color shift, washed out images and an observable raise in the darkness levels produced by a damaged LCD panel.

In order to help prolong the onset of such damage a set of UV and IR band filters and mirrors can be used to minimize the amount of harmful energy that is conveyed to the LCD panel from the illuminator. In order to determine what combination of filters and mirrors are best for any particular application it is important to know how each material reacts to the various intensities of bandwidths emitted by your chosen illuminator.

Frequently the Illuminators used in LCD systems are gas discharge lamps such as xenon arc lamps and metal halide light sources. A standard hot mirror that reflects energy between 750 and 1200 nm can be used to mitigate the majority of IR energy being conveyed to the LCD panel. In addition a UV blocker can be used to mitigate the damage from energy below 400 nm.

Other thin film coatings and substrates can be utilized to reduce the IR and UV damage to an LCD panel. Any solution must be well researched to minimize concerns so that a sufficient cooling mechanism is planned and allowed for in the application.

The use of liquid crystal displays (LCDs) in user interface assemblies is widespread across nearly all industries, locations, and operating environments. Over the last 20 years, the cost of LCD displays has significantly dropped, allowing for this technology to be incorporated into many of the everyday devices we rely on.

The odds are high you are reading this blog post on a laptop or tablet, and it’s likely the actual screen uses LCD technology to render the image onto a low-profile pane of glass. Reach into your pocket. Yes, that smartphone likely uses LCD technology for the screen. As you enter your car, does your dashboard come alive with a complex user interface? What about the menu at your favorite local drive-thru restaurant? These are some everyday examples of the widespread use of LCD technology.

But did you know that the U.S. military is using LCD displays to improve the ability of our warfighters to interact with their equipment? In hospitals around the world, lifesaving medical devices are monitored and controlled by an LCD touchscreen interface. Maritime GPS and navigation systems provide real-time location, heading, and speed information to captains while on the high seas. It’s clear that people’s lives depend on these devices operating in a range of environments.

As the use of LCDs continues to expand, and larger screen sizes become even less expensive, one inherent flaw of LCDs remains: LCD pixels behave poorly at low temperatures. For some applications, LCD displays will not operate whatsoever at low temperatures. This is important because for mil-aero applications, outdoor consumer products, automobiles, or anywhere the temperature is below freezing, the LCD crystal’s performance will begin to deteriorate. If the LCD display exhibits poor color viewing, sluggish resolution, or even worse, permanently damaged pixels, this will limit the ability to use LCD technologies in frigid environments. To address this, there are several design measures that can be explored to minimize the impact of low temperatures on LCDs.

Most LCD displays utilize pixels known as TFT (Thin-Film-Transistor) Color Liquid Crystals, which are the backbone to the billions of LCD screens in use today. Since the individual pixels utilize a fluid-like crystal material as the ambient temperature is reduced, this fluid will become more viscous compromising performance. For many LCD displays, temperatures below 0°C represent the point where performance degrades.

Have you tried to use your smartphone while skiing or ice fishing? What about those of you living in the northern latitudes - have you accidently left your phone in your car overnight where the temperatures drop well below freezing? You may have noticed a sluggish screen response, poor contrast with certain colors, or even worse permanent damage to your screen. While this is normal, it’s certainly a nuisance. As a design engineer, the goal is to select an LCD technology that offers the best performance at the desired temperature range. If your LCD display is required to operate at temperatures below freezing, review the manufacturer’s data sheets for both the operating and storage temperature ranges. Listed below are two different off-the-shelf LCD displays, each with different temperature ratings. It should be noted that there are limited options for off-the-shelf displays with resilience to extreme low temperatures.

For many military applications, in order to comply with the various mil standards a product must be rated for -30°C operational temperature and -51°C storage temperature. The question remains: how can you operate an LCD display at -30°C if the product is only rated for -20°C operating temperature? The answer is to use a heat source to raise the display temperature to an acceptable range. If there is an adjacent motor or another device that generates heat, this alone may be enough to warm the display. If not, a dedicated low-profile heater is an excellent option to consider.

Made of an etched layer of steel and enveloped in an electrically insulating material, a flat flexible polyimide heater is an excellent option where space and power are limited. These devices behave as resistive heaters and can operate off a wide range of voltages all the way up to 120V. These heaters can also function with both AC and DC power sources. Their heat output is typically characterized by watts per unit area and must be sized to the product specifications. These heaters can also be affixed with a pressure sensitive adhesive on the rear, allowing them to be “glued” to any surface. The flying leads off the heater can be further customized to support any type of custom interconnect. A full-service manufacturing partner like Epec can help develop a custom solution for any LCD application that requires a custom low-profile heater.

With no thermal mass to dissipate the heat, polyimide heaters can reach temperatures in excess of 100°C in less than a few minutes of operation. Incorporating a heater by itself is not enough to manage the low temperature effects on an LCD display. What if the heater is improperly sized and damages the LCD display? What happens if the heater remains on too long and damages other components in your system? Just like the thermostat in your home, it’s important to incorporate a real-temp temperature sensing feedback loop to control the on/off function of the heater.

The next step is to determine the number of temperature sensors and their approximate location on the display. It’s recommended that a minimum of two temperature sensors be used to control the heater. By using multiple sensors, this provides the circuit redundancy and allows for a weighted average of the temperature measurement to mitigate non-uniform heating. Depending on the temperature sensors location, and the thermal mass of the materials involved, the control loop can be optimized to properly control the on/off function of the heater.

Another important consideration when selecting a temperature sensor is how to mount the individual sensors onto the display. Most LCD displays are designed with a sheet metal backer that serves as an ideal surface to mount the temperature sensors. There are several types of thermally conductive epoxies that provide a robust and cost-effective way to affix the delicate items onto the display. Since there are several types of epoxies to choose from, it’s important to use a compound with the appropriate working life and cure time.

For example, if you are kitting 20 LCD displays and the working life of the thermal epoxy is 8 minutes, you may find yourself struggling to complete the project before the epoxy begins to harden.

Before building any type of prototype LCD heater assembly, it’s important to carefully study the heat transfer of the system. Heat will be generated by the flexible polyimide heater and then will transfer to the LCD display and other parts of the system. Although heat will radiate, convect, and be conducted away from the heater, the primary type of heat transfer will be through conduction. This is important because if your heater is touching a large heat sink (ex. aluminum chassis), this will impact the ability of the heater to warm your LCD display as heat will be drawn toward the heat sink.

Insulating materials, air gaps, or other means can be incorporated in the design to manage the way heat travels throughout your system on the way toward an eventual “steady state” condition. During development, prototypes can be built with numerous temperature sensors to map the heat transfer, allowing for the optimal placement of temperature sensors, an adequately sized heater, and a properly controlled feedback loop.

Before freezing the design (no pun intended) on any project that requires an LCD display to operate at low temperatures, it’s critical to perform low temperature first. This type of testing usually involves a thermal chamber, a way to operate the system, and a means to measure the temperature vs time. Most thermal chambers provide an access port or other means to snake wires into the chamber without compromising performance. This way, power can be supplied to the heater and display, while data can be captured from the temperature sensors.

The first objective of the low-temperature testing is to determine the actual effects of cold exposure on the LCD display itself. Does the LCD display function at cold? Are certain colors more impacted by the cold than others? How sluggish is the screen? Does the LCD display performance improve once the system is returned to ambient conditions? These are all significant and appropriate questions and nearly impossible to answer without actual testing.

As LCD displays continue to be a critical part of our society, their use will become even more widespread. Costs will continue to decrease with larger and larger screens being launched into production every year. This means there will be more applications that require their operation in extreme environments, including the low-temperature regions of the world. By incorporating design measures to mitigate the effects of cold on LCD displays, they can be used virtually anywhere. But this doesn’t come easy. Engineers must understand the design limitations and ways to address the overarching design challenges.

A full-service manufacturing partner like Epec offers a high-value solution to be able to design, develop, and manufacture systems that push the limits of off-the-shelf hardware like LCD displays. This fact helps lower the effective program cost and decreases the time to market for any high-risk development project.

projection lamp, which may be associated with a smell of burning plastic and/or heat damage outside of the TV. Sony claims that they have internally evaluated the problem, and that it does not pose a safety risk, but many of the pictures are disturbing.

safety issue (potential injury or property damage), I encourage you to In responses to CPSC incident reports by consumers, Sony consistently provides the following statement: "Sony has determined that product in question does not create an

In some cases, Sony claimed that they were out of the repair kits. In other cases, Sony claimed that the heat damage was too severe to repair. In many cases, customers have both an optical block problem and the melting issue, which is not surprising since heat is a contributing factor to optical block failure. Adding insult to injury, in some of these latter cases, Sony apparently justified their position that the TV was not repairable by citing the optical block problem, as opposed to physical heat damage to parts.

Might be normal for some, but it is not normal for all LCD displays. The LCD on the AC directly below the radio is not effected at all by heat. Between my wife and I we"ve owned 7 cars since moving to Arizona, plus I"ve changed the head units in 3 or 4 of those. None of those have had any kind of display problem at all. I"d say that makes this BMW unit somewhat unique.

iPads are some of the most popular electronic devices on the market, and they are also very fragile. If the user does not store and care for these devices properly, they can become damaged or broken very easily. Owners most often report a damaged iPad screen. Water, heat, force and pressure most often cause this damage.

When consumers seek iPad screen replacement services, it is usually because their iPad has been exposed to excessive heat. Leaving the device in a hot car or on a heated surface for a period of time can leave the screen distorted and warped. This can be even more frustrating if you have purchased your iPad recently.

If the screen has heat damage, obviously it will need either repair or replacement. The best option for replacement is to take your device to a reputable repair shop that has been authorized to work on Apple products. This way, you will know that your iPad screen will be replaced back to out of the box condition.

Most people know that water or other liquids should never come into contact with electronic devices such as iPads. However, this does not mean that there are not many accidental spills that cause screen damage on iPads. Water can even leak inside the iPad and causeinternal damage as well.

If your iPad’s screen has been damaged, you will find numerous DIY guides, tutorials and videos online. Although these guides seem to offer the perfect solution for you to save money on screen replacement services, you should not attempt to repair the device on your own unless you have extensive knowledge about iPad repair. DIY repairs can cause irreversible damage to your iPad.

The best way to avoid having to search for iPad screen replacement services is to get a screen protector for your device. The protector will keep your device looking newer longer. However, if the screen does need to replacing, you can hire the services of knowledgeable and skilled repair technicians who can fix all of your iPad repair issues.

LCD screens use liquid crystal molecules for display and these molecules align to give the desired display pattern. However, exposure to lower temperatures can create bubbles or aggregate liquid molecules (meaning disturbed molecule order), hence leading to permanent damage to the display. It is quite common to observe dimming and screen blackouts at lower temperatures. So, the next time your display turns sluggish, try keeping it in your pockets!

Cold weather can also cause damage to the circuit board, similar to how a paved road cracks over time when exposed to hot and cold temperatures (because the concrete expands and contracts with the fluctuations in temperature). The same can happen with your cell phone, which causes poor circuit connections over time.

Mobile devices aren’t meant to last forever. However, cold temperature damage is often overlooked as the resulting damage doesn’t happen immediately. It’s still a good idea to consider the impact it might have as device costs are increasing and you’ll want to preserve the resale value of your phone or tablet when the time comes to upgrade.

just to recap quickly: one day I turned on my laptop and there was a big nasty crack down the screen running from the top in a jagged line across to the side. the machine was never dropped, hit or abused in any way, so to anyone out there who doubts that this kind of thing can just happen... well, it can.

anyway, after taking the machine to an authorised repair centre, instead of contacting apple for a warranty repair as I"d asked them to do, they just sent me a quote to replace the screen at a cost of around 950€. now, if I"d dropped my computer, or some accident had happened to it, I would have just had to swallow it and accept that this is how things go. but seeing as nothing like that had ever happened, it"s a little harder to come around to thinking you are going to have to shell out for something that obviously was defective and snapped all of its own accord. the repair centre suggested that if I wasn"t happy with the quote I should take it up directly with apple..

so, I called apple france the next day and explained the situation. it was a little tricky because my MBP is now a month or so out of warranty, however it was still under warranty at the date when I handed it over for repair. so fortunately I had documentation to prove that. after a lengthy conversation and being put on hold a couple of times, the consultant told me that they would need to speak with the technician that had assessed the machine. if the technician would verify that there were no signs of abuse on the computer, they"d replace the display under warranty. so they put me on hold again and called the repair centre. when they got back to me, the confirmed that whatever happened to my display was not the result of any damage accidental or otherwise, and they would authorise repair under warranty.

The TV Shield). The TV Shield fans and heaters are thermostatically controlled. Fans turn on at 88 degrees and off at 78 degrees. Heaters turn on at 39° F and turn off at 48° F.

fireplace (keep in mind if the TV is on a full motion mount and being pulled and left out from the wall often when heat is present, that can increase heat damage risk)

TV enclosure. Even then, enclosures are designed to handle hot environments but necessarily direct concentrated high heat, so you"d still want the enclosure to be a bit distanced from anything like heaters and choose an enclosure with fans to keep the inside of the unit and TV at regulated temperatures.

designed to be fire resistant by any means. If you have any uncertainty concerning The TV Shield and hot environments, contact us any time to explain your application and we"ll be able to advise. Enclosures resist heat better than