lcd screen heat damage free sample

Have you ever left your TV or monitor on for days, stuck on the same image? You return to your screen, only to find an image burned into the display. No matter what you do, it won"t go away. It is a permanent image burn.

Why do monitors and TVs get image burn? Why can"t manufacturers prevent LCDs and plasma screens from a burnt image imprint? Moreover, what can you do to fix an image burn?

Before flat-screens and crystal displays, most TVs and monitors featured CRT (Cathode Ray Tube) technology. In CRTs, individual pixels comprise a red, blue, and green phosphor component. Depending on the intensity of each phosphor component, the pixel appears to the human eye as a unique color.

When a particular still image remains for too long, the intensity of each phosphor component diminishes at an uneven rate. The result is a ghost image on the screen, which is known as image burning.

This is a very simplified version of how a plasma screen works. However, the main thing to understand is that plasma screens use phosphor material (like CRTs) to turn those photons into images.

LCD and LED do not work in the same way as CRTs, either. LCD and LED screens use backlit liquid crystals to display colors. Although manufacturers market screens using LED and LCD, an LED screen is still a type of LCD. The white backlight filters through the liquid crystals, which extract particular colors per pixel.

LCD and LED displays don"t suffer from the same type of image burn as CRTs and plasma screens. They"re not completely clear, though. LCD and LED screens suffer from image persistence. Read on to find out more about image persistence.

Before you can fix screen burn-in, take a second to understand why these images burn in the first place. LCDs and LEDs don"t suffer from burn-in as seriously as plasma screens. But static images can leave an imprint on both display types if left alone for too long. So, why does image burn happen?

First, let"s tackle plasma screen burn-in. Remember why CRTs experience image burn? When a still image remains on the screen for too long, the phosphor components in each pixel wear out at different rates. The uneven burn rates leave behind a ghost image, forever etched into the screen.

Plasma screens also suffer from phosphor deterioration. Plasma burning occurs when pixels on the screen are damaged through long exposure. The phosphor loses its intensity and only shows the light it was fed repeatedly. In this case, the still image, which causes the burn.

LCD and LED screens can also experience image burn, though the image burn process can take longer to develop into a permanent issue. In addition, LCD and LED screens suffer from another issue, known as image retention (also known as image persistence or an LCD shadow).

Image retention is a temporary issue that you are more likely to notice before it becomes a permanent issue. However, proper image burn can still affect LCD, LED, and OLED screens.

Image retention is a different issue from image burn (although it is a precursor to image burn). For example, you"re using an image of a steam train as a reference point for a drawing. You have the steam train image on your screen for a few hours before you decide to play a video game instead.

When you load up the video game on the screen, you can still see the faint outline of the steam train on the screen. The steam train image will remain for a short while, but the movement and color changes of the video game (or film, TV show, or other media type) should erase the retained image.

The other thing to consider is that LED and OLED image burn-in, when it happens, is irreversible. That"s because of how LED and OLED screens work. Individual pixels within an LED display decay when they emit light.

Under normal use, an LED, OLED, or QLED screen won"t suffer image burn. However, if you leave your screen on a single channel for hours every day, then burn-in can become an issue, as it would with almost any screen.

Issues arise when a screen shows a single news channel 24 hours a day, every day, causing channel logos to burn-in, along with the outline of the scrolling news ticker and so on. News channels are a well-known source of television burn-in, no matter the screen type.

Image burn-in fixes exist for LCD and plasma screens. How effective an image burn-in fix is depends on the screen damage. Depending on the length and severity of the image burn, some displays may have permanent damage.

The best fix for screen burn is to prevent it in the first place. Okay, that isn"t super useful if your screen is already experiencing image burn. However, you should always try not to leave your screen on a still image for too long. The time it takes for an image to burn-in varies from screen to screen, between manufacturers, sizes, and panel type.

Another prevention method is to reduce screen contrast as much as you can. Unfortunately, most screens aren"t calibrated correctly, often pushing the contrast and brightness settings too high.

Lower contrast means the lighting across your screen is more even. This means less strain on specific areas of the screen, which helps protect against image burning.

If your plasma or LCD screen already has image burn-in, you can try turning on white static for 12 to 24 hours. The constant moving of white-and-black across your screen in random patterns can help remove the ghost image from your screen.

Unfortunately, this won"t work for extreme cases. Some TVs will have a built-in pattern swiping option that basically accomplishes the same thing (filling your screen with random patterns).

Pixel-shift constantly slightly adjusts the image on your screen, which varies the pixel usage to counteract image burn. You might have to enable a pixel or screen shift option in your screen settings. Pixel-shift is a handy feature for LED and OLED screens that cannot recover from image burn and should help counteract an LCD shadow.

Other modern screens feature built-in screen refresh functions that the manufacturer will advise using to remove image retention and image burn issues.

The best tool for fixing ghost images is JScreenFix. The original program helps fix monitors with dead pixels, but the same company also released an "advanced" version of the tool, known as JScreenFix Deluxe.

While the Deluxe version uses advanced algorithms to repair burned screens and prolong plasma and LCD longevity, the official site is no longer up and running, and there is no way to download the full version officially.

If you have television burn-in, you can attach a laptop to your TV using an HDMI cable, extend your desktop to the television, and share the white screensaver. Hopefully, that will shift your television burn-in.

The team over at ScreenBurnFixer offers a few different ways you can attempt to fix screen burn on your TV or monitor. As with any other screen burn-in fixes, their chance of working depends on the scale of the issue.

You can head to the ScreenBurnFixer Video page and find a video that matches your screen type, then let the video play for as long as possible (we"re talking multiple hours, not a quick half an hour blast). Alternatively, head to the Chart page and find your device or a device that matches your specifications.

There are several ways you can attempt to fix screen burn-in. The results will vary between the screen type and the level of burn-in. A screen with extensive image burn may not clear entirely, although you might see an improvement.

Some screen degradation over time is understandable. However, if you follow the steps in this guide, you"ll protect your screen from image burn before it becomes a permanent issue.

Liquid crystal displays (LCD) have become an essential component to the industry of display technology. Involved in a variety of contexts beyond the indoors like LCD TVs and home/office automation devices, the LCD has expanded its usage to many environments, such as cars and digital signage, and, thus, many temperature variations as well.

As with any substance that requires a specific molecular characteristic or behavior, LCDs have an operating temperature range in which the device, if within, can continue to function properly and well. In addition to that, there is also an ideal storage temperature range to preserve the device until used.

This operating temperature range affects the electronic portion within the device, seen as falling outside the range can cause LCD technology to overheat in hot temperatures or slow down in the cold. As for the liquid crystal layer, it can deteriorate if put in high heat, rendering it and the display itself defective.

In order for the LCD panel to avoid defects, a standard commercial LCD’s operation range and storage range should be kept in mind. Without adaptive features, a typical LCD TV has an operating range from its cold limit of 0°C (32°F) to its heat limit of 50°C (122°F) (other LCD devices’ ranges may vary a bit from these numbers).

The storage range is a bit wider, from -20°C (-4°F) to 60°C (140°F). Though these ranges are quite reasonable for many indoor and even outdoor areas, there are also quite a few regions where temperatures can drop below 0°C or rise above 32°C, and in these conditions, LCDs must be adapted to ensure functionality.

Heat, can greatly affect the electronics and liquid crystals under an LCD screen. In consideration of heat, both external heat and internally generated heat must be taken into consideration.

Seen as the liquid crystals are manipulated in a device by altering their orientations and alignments, heat can disrupt this by randomizing what is meant to be controlled. If this happens, the LCD electronics cannot command a certain formation of the liquid crystal layer under a pixel, and the LED backlighting will not pass through as expected, which can often lead to dark spots, if not an entirely dark image. This inevitably disrupts the display’s readability.

Depending on the upper limit of the operation temperature range, LCD device can be permanently damaged by extreme heat. With long exposure to extreme heat, besides the destruction of the liquid crystals, battery life can shorten, hardware can crack or even melt, response time may slow to prevent even more heat generation from the device.

The LED backlight and the internal circuitry, typically TFT-based in the common TFT LCDs, are components that can generate heat that damages the device and its display. To address this concern with overheating, many devices use cooling fans paired with vents.

Some devices that are used in extremely high ambient temperatures may even require air conditioning. With air vents to carry the heat out, the device can expel it into the surroundings.

But this leads to another problem: how can moisture be prevented from entering through the vent? If moisture enters the device and high heat is present, condensation can occur, fogging the display from inside, and in some cases, short-circuiting may cause the device to turn off. In order to circumvent this issue, the shapes of the air vents are specific in a way that allows only for air movement, not forms of moisture.

In the opposite direction is extreme cold. What typically occurs in the cold is “ghosting” (the burning of an image in the screen through discoloration) and the gradual slowing and lagging of response times. Like heat-affected LCD modules, the extreme temperature can affect the liquid crystals. This layer is a medium between the liquid and solid state, so it is still susceptible to freezing.

An LCD device can be left in freezing temperatures because it will likely not be permanently damaged like in the heat, but it is important to understand the device’s limits and how to take precautions when storing the device. The standard and most common lower-bound storage range limit is -20°C, below freezing, but if possible, it would be best to keep it above that limit, or else there is still a risk of permanent damage.

If the device is not adapted for the cold, it would be good to keep it bundled up, trapping the heat within layers. However, this is only a temporary solution. Adapted, rugged devices have advantages such as screen enclosure insulation for heat level preservation and, in more extreme cases, heaters to generate extra heat to raise the internal temperature to a level above the minimum.

Display types have a lot of variation. Choices like alphanumeric or graphic LCD, human-machine interactive LCD modules and touchscreen panels capabilities, the width of the viewing angle, level of contrast ratios, types of backlighting, and liquid crystal alignment methods are often considered. For example, the twisted nematic LCD provides for the fastest response time at the lowest cost, but cannot offer the highest contrast ratio or widest viewing angle.

Environment-based factors must consider things besides the obvious temperature like UV exposure and humidity/moisture, as they all are necessary in finding the perfect fit extreme temperature LCD module.

Besides the LCD modules, recent new products have opened doors in wide temperature range displays, such as OLED displays. OLED displays offer better displays in regard to contrast, brightness, response times, viewing angles, and even power consumption in comparison to traditional LCD displays.

Yes, it happens. It was 2013 when I had a phone call from BenQ, a multinational manufacturer of LCD monitors. The project manager mentioned that one kind of LCD TV screen they were currently shipping damage. BenQ team looked for a solution from us to prevent broken TV monitors when shipped because defective products are not what any good business would want to do.

It was BenQ’s biggest embarrassment. They had a factory in mainland China and every time certain models of LCD screens were produced, they would be shipped to PChome Taiwan for sale. However, the recent damage rate of the goods had been abnormally high up to nearly 20%. Taking preventive measures, such as adjustment of packaging materials or structure, etc., there is no significant effect.

The situation became increasingly serious and it’s not just that it was BenQ who noticed this problem; customers’ feedback also showed that their LCD TVs were suffering from abnormal damages when delivered to them. Without any big accidents happening during the transportation or delivery process at all – one could only imagine what was going on inside those.

And now, with excessive losses and customers’ claims, BenQ had no idea how to do and kept seeking solutions from others, finally, they notice Impact Label through others’ introductions and heard that the label can reduce damage rates by 40-60%.

We had conducted a study on what type of shock can affect the LCD screen and how much damage it entails. We first put types of indicators labels in the box of the LCD panel in order to determine how much force damage would occur during regular shipment and transit.

According to the results of the test, the impact force on the cargo’s bottom is more than the acceleration of 50G, and this impact may damage the screen.

In addition, we observed that these impacts may cause a variety of different damages to screens: scratches on protective glass; or impairing light colors by undergoing color change from long-term use so that they become grayish black patches–which will affect a customer’s viewing experience.

Something wonderful happened. When the Impact Label indicator is in place, the damage rate of products was reduced to 0%. BenQ was enthusiastic and apprehensive, and would like to try a couple more batches.

After several weeks of discussion and debate, BenQ internally decided to adopt an impact monitor to decrease the risk of transportation damage, as the ratio of cargo damage reduced from 20% to 2%. In the next, all package is written “reminder before receipt” on outside the box. Customers can reject shipment if the Impact Label is RED upon arrival.

A study shows the damage rate typically drops by 50% or more when a monitor is in place. The TV screens are rarely damaged in this case, which proves the statement.

From customers’ point of view, the indicator label provides simple reminders of a concealed damage, and the time it takes to process the damaged product after purchase.

As for sellers, the Impact Label reduces the rate of damaged goods and makes business better. More importantly, the cost derived from customer complaints is lower and provides indisputable evidence of mishandling for freight claims.

Managing damage in the supply chain has many options, redesign the package is always the first impression comes to mind, however, it’s more expensive.

In fact, change the handling environment is the fastest and most effective way to solve damaged LCD TV screens, and where Impact Label comes to play! BenQ is not the first user of impact indicators in LCD TV manufacturers. To comply with your LCD TV, our free consultant and free samples for testing are waiting for you.

An LCD is also called a liquid-crystal display, which is one kind of flat-panel display or other electronically modulated optical device. For the LCD technology, they are used in a wide range of applications, including LCD TVs, computer monitors, instrument panels, aircraft cockpit displays, security CCTV monitors, and indoor and outdoor signage.

Small LCD screens are also common and popular in portable consumer devices like digital cameras, watches, digital clocks, calculators, smartphones, etc.

As we provide world-class display solutions, we aim to fulfill all the needs of viewing applications; thus, there are a cascade of sizes of our LCD screens, such as LCD video walls, LCD TVs, large format LCD displays, etc. All of these products have quite sensitive screens, and complicated electrical components and circuits, and they are extremely delicate and must be handled slowly with care. Also, the antireflection coating on the glass of the LCD screen is pretty fragile. Once damage occurs to the LCD screen, we can’t fix it, but only replace the set. At the end of the day, our LCD screens, LCD TVs are very fragile, especially for big LCD screens.

During transit, handlers must avoid rubbing, tapping, hitting, knocking, dropping the LCD screens, and also need to prevent them from severe vibration, or the glass will be cracked and lead to the worst consequence, malfunction.

At first, we only used shock indicators for a fraction of our items, and we noticed that with these devices affixed to every single product we shipped, our damage rate dropped by around 58%. Hence, we decided to put one rule into effect immediately, which is using shock indicators on all of our shipments.

The display controller, UC1611, is no longer available in the form of bonding on the PCB which is how Crystalfontz has used it for this design. We are designing a drop-in replacement that uses the UC1611 heat seal package, which will continue to be supported, instead of the PCB bonding package.

This component package change requires us to alter the PCB by moving some components around so that the heat seal tool can be used without causing damage to any components.

First, this was by making sure I was describing the LCD backlight vs. the RGB enclosure lighting - then, once they fully understood my concerns about the brightness, quickly getting back to me & providing detailed instructions with photos to ensure that I understood how to confidently make the most of my purchase.

I buy a lot of good stuff on Amazon, but don"t write a ton of reviews... Rarely do I have an opportunity for such a great interaction with a vendor on Amazon with a product that meets my needs so well, though... This felt so exceptional that I was inspired to share my own experience regarding both the manufacturer/vendor FormulaMod & their 8.8" LCD itself.

Turn the panel over so that you"re working on the front of the panel. Place the panel on a book or the edge of the table, so that the pins hang over the edge and don"t get damaged while you"re working on the panel.

Use the razor blade to trim the film to the left and right sides and the bottom of the panel. If the film hangs over the top of the viewable area of the panel, that"s fine, but do not try to trim it from the top side, as the IC and conductive traces are easily damaged.

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.

TFT LCD image retention we also call it "Burn-in". In CRT displays, this caused the phosphorus to be worn and the patterns to be burnt in to the display. But the term "burn in" is a bit misleading in LCD screen. There is no actual burning or heat involved. When you meet TFT LCD burn in problem, how do you solve it?

When driving the TFT LCD display pixels Continously, the slightly unbalanced AC will attract free ions to the pixels internal surface. Those ions act like an addition DC with the AC driving voltage.

Those burn-in fixers, screen fixer software may help. Once the Image Retention happened on a TFT, it may easy to appear again. So we need to take preventive actions to avoid burn in reappearing.

For normal white TFT LCD, white area presenting minimal drive, black area presenting maximum drive. Free ions inside the TFT may are attracted towards the black area (maximum drive area)

When the display content changed to full screen of 128(50%) gray color, all the area are driving at the same level. Those ions are free again after a short time;

The use of consumer electronics incorporating LCD-based screens including computers, laptops and smartphones is continuing to increase. However, the LED backlight modules emit extensive blue light that can damage retinal photoreceptors and RPE cells and alter circadian rhythms owing to its short wavelength and high energy, eventually becoming a health hazard. Here, we investigated the effects of the emitted light spectrum of LCDs on LED-induced retinal photoreceptor cell damage and elucidated the detailed mechanisms. As traditional blue light filters and blocking lenses may decrease the luminance of light and reduce the color and contrast sensitivity and visual quality, we alternatively designed LCDs with differing energy emission but the same luminance by adjusting the phosphor ratio and modulating the emitted light spectrum. We also established an index of LCD energy emission, termed OEEI, the value of which is represented by the radiant flux produced by each luminous flux and could be used to evaluate the light hazards. The results of the present study indicated that LCDs with higher OEEI caused stronger light-induced photoreceptor cell damage through the production of ROS and activation of the NF-κB pathway, along with upregulation of protein expression associated with inflammatory response and apoptosis.

In particular, exposure to an LCD with luminance of 300 nits for three days decreased the viability of 661W photoreceptor cells. However, compared to the effects of the LCD with low OEEI, LCD with higher OEEI induced increased levels of cell death and the percentage of apoptotic cells was also higher. Moreover, the effect was OEEI-intensity dependent. Based on the analysis of the emitted light spectrum, the major difference among the three OEEI groups was the radiance of shorter wavelength blue light and green light. Blue light energy emission was much higher in the high OEEI group than that in the medium and low OEEI groups. Although green light energy emission was also higher in the high OEEI group, the photoreceptor-derived cell damage caused by blue light was much more serious than that caused by green light [29]. LCD exposure-induced photoreceptor cell damage could, therefore, be mainly attributed to the level of emitted blue light energy.

Our study demonstrated that the decline of cell viability after LCD exposure was due to elevated cellular ROS formation and mitochondrial dysfunction. Oxygen radicals initiate free radical chain reactions and the oxidative stress results in cellular dysfunction and cell death [30,31]. The effect is stronger in the outer retina because choriocapillaries provide higher concentrations of oxygen. Therefore, 661W photoreceptor cells constitute a good model for studying these effects. In addition, mitochondrial dysfunction can serve as a predictor of cell injury and apoptosis as the mitochondrion is essential for cellular physiological functions and energy production. In the present study, JC-1 staining was used as the indicator of mitochondrial membrane potential damage [32]. Light induces retinal injury through the production of free radicals, oxidative stress, and the damage of mitochondrial membrane potential, as previously reported [15,16,33,34]. The results of our study revealed that lower OEEI exposure produced less ROS, induced less oxidative stress and mitochondrial damage, and subsequently led to decreased apoptosis and cell death compared to that from high OEEI exposure.

NF-κB consists of a family of transcription factors which play critical roles in immunity, inflammation, cell proliferation, differentiation, and cell survival. In order to elucidate the molecular mechanism of the increased oxidative stress and cell apoptosis caused by LCD with higher OEEI, we used western blot analysis and EMSA to evaluate the expression of inflammation and apoptosis-related proteins and the modulation of the NF-κB system. The results of our study revealed that the expression of proteins associated with oxidative stress, inflammation, and the apoptotic pathway all increased in 661W cells exposed to LCD with higher OEEI. In particular, iNOS and HO-1 comprise oxidative stress-related proteins that could be induced in an oxidative environment such as blue light exposure [35,36]. Both ICAM-1 and MCP-1 are pro-inflammatory cytokines that facilitate leukocyteendothelial transmigration, enhance inflammatory vascular permeability, advance cellular extravasation reaction, and promote signal transduction to produce inflammatory effects [37,38,39,40]. Therefore, ICAM-1 and MCP-1 function as strong pro-inflammatory mediators and could be used as indicators to assess the inflammatory status. In comparison, caspase-3 is a marker of cell apoptosis; notably, the cleavage forms of caspase-3 were obviously observed in the group with higher OEEI exposure. Among these, ICAM-1, iNOS, and, MCP-1 are regulated by NF-κB [41,42,43]; in turn, the NF-κB system can be induced by ROS production [44,45]. The result of EMSA in our study demonstrated that exposure to LCDs with higher OEEI activated the NF-κB pathway. Taken together, the findings of the present study suggested that LCD exposure induced oxidative stress and then upregulated the NF-κB pathway. Consequently, it further upregulated NF-κB downstream genes and enhanced the expression of oxidative stress, inflammation, and apoptosis-related proteins, finally inducing cell death. The effect was correlated with OEEI intensity, which also represented LCD energy emission, especially that of blue light.

Our study had some limitations. First, this was an in vitro study. We used 661W cell line as our model system and the cells were still dividing and not fully differentiated. 661W cells have the potential to differentiate into neuronal cells with the treatment of staurosporine [46]. Caspases are also involved in some non-apoptotic processes including cell differentiation [47]. The mechanisms of apoptosis and caspase-mediated cell death may not be the same as that in the well-differentiated human retinal photoreceptors. However, 661W cells express cone photoreceptor features and respond to light stimulation [48]. This cell line has been widely used as the model of light-induced retinal damage in several studies [25,26,27,28,29]. Based on our results, the cleavage forms of caspase-3 were obviously observed in medium and high OEEI group but not in the control or low OEEI group. It implied that apoptosis rather than cell division or differentiation played the major role in the expression of caspases. Further research with primary retinal cell culture or animal experiments may be needed to confirm our results. The exact effect on the human retina and other aspects of light hazards require further investigation. Second, the majority of our experiments were performed under the condition of 3-day exposure with a luminance of 300 nits. Our findings are not necessarily generalizable to other conditions such as higher luminance or longer exposure times. The chronic cumulative effects of daily blue light exposure may cause more photochemical damage. However, the luminance of displays for laptops and other mobile devices is usually between 200 and 300 nits on average. Our results therefore still provided useful information regarding LCD exposure-induced retinal damage in daily life. Third, the visible light spectrum and emitted energy spectrum of the LCDs in our experiments were fixed. We could not analyze the effect of other specific patterns of light spectra and determine the most appropriate light source to maintain eye health. Further studies with specific light spectrum modulation should be considered.

On top of call difficulties, a broken speaker can also cause problems when watching videos or listening to podcasts. First, carefully check your phone to determine if there is any external damage. If nothing is visible, make sure the latest software update is installed on your device. In addition, try some basic troubleshooting by turning your phone on and off while leaving it unplugged.

Once a phone has water damage — from small spills to a full liquid plunge — there’s often no easy fix. The first step should be to check if your smartphone’s Liquid Contact Indicator has been activated. Most models, including Apple, LG and Samsung, have small visible indicators to show whether water damage has occurred. Consider peace of mind for those inevitable accidents with Verizon’s Verizon Protect or  Total Mobile Protection. Not only is your phone covered if it gets water damage, you may be eligible for a full replacement that same day.

From the rays in a hot car to a sunny day spent at the beach, high temps and direct sunlight can cause serious and lasting damage to a smartphone. Extreme heat can damage a smartphone’s internal components and result in slower speeds or even loss of data. And often the damage is not visible from the outside.

Before you panic, get your phone back to room temperature and exit all apps. Look over the exterior of the phone to see if the battery, which is especially sensitive to extreme heat, has leaked. And in all future situations, make sure to follow manufacturer recommendations. For example, Apple recommends not using a smartphone in temperatures above 95 degrees Fahrenheit.

The Macbook Pro 13" LCD display is hard to dismantle. With the iBooks and PowerBooks and even plastic macbooks models it was easy to swap the panel case, only 2 or 4 screws to unscrew and the job was done but with the unibody MBP 13"/15"/17" Apple made it more difficult. You need to heat the glued front glass to take it out and have access to the screws that retain the LCD screen. Doing this would probably void the warranty if you still have one and you could also damage the LCD if too much heat is applied to the screen. A complete LCD display swap would be more secure but would also cost much more.