A display inverter is a small circuit board in a laptop that passes a current of energy from the machine body to the attached liquid crystal display (LCD). It works by transforming a direct electrical current from the motherboard into an alternating current. The alternating current then turns on what is known as a “backlight”, a complex series of signals that cause the images generated from the hard drive to appear on the screen. This instrument is also often known as a backlight inverter or LCD inverter, among other names. It is extremely important for the proper functioning of the laptop, but it is usually one of the first things to fail in an aging machine. Repairs are sometimes possible, but not always, and in any case tend to require a little experience.
A screen inverter creates the image displayed on a laptop screen.
The inverter’s main function is to power the laptop’s LCD. To some extent, this means that it is responsible for channeling power from the mainframe to the screen so that the screen illuminates and projects accurate images. Standalone “desktop” computers often have displays that are completely separate from their hard drives, and inverters in these configurations do not work the same way. Some translation is still required, but it is usually done via an external cable connected to a graphics card. In a laptop, everything is built together, which means these connections have to happen internally. The screen inverter performs this function.
Laptop repairs are sometimes possible, but not always, and in any case they tend to require a bit of experience.
How it works
Inverter boards have become smaller and of better quality as laptop technology has improved, and as a result, their performance has gotten better and more reliable. On most laptops, this device looks like a thin strip with various switches and wires and is usually located just below the LCD screen, right on the hinge where the top folds over the keyboard; people can access it by removing the plastic frame around the screen. It is normally connected at one end to the internal video line and at the other end to the backlight. In addition to powering the screen, the inverter also creates better screen resolution and can give users more control over display options. Its main task is to scramble and interpret electrical currents.
Even if the device performs a seemingly simple task, when it fails, the results are often impractical. Connection or wiring difficulties can mean that the screen will appear to be backlit, but the light will be very dim and images can be very difficult to see. This can make the computer difficult and frustrating to use, even if the memory and hard drive are in perfect working order. The LCD may also display very faint images or the laptop may appear to be turning on but the screen remains dark.
Faulty circuits or bad conductor coils are two of the most common causes of inverter problems. In such cases, it can sometimes be difficult to determine if the backlight has just burned out or if the inverter is faulty. The symptoms for each are very similar and both can display a dark or slightly lit screen with some or no image, but inverter problems are often more difficult to correct. The backlight is often more like a light bulb that can simply be replaced; the drive is a more complex piece of hardware that often needs more extensive repairs and rework.
The easiest thing people can do when they suspect a bad screen reverse is take their machine in a repair shop, but this can get expensive. In most cases simple tweaks and reconnections can be done at home, provided people have some understanding of computer engineering.
There are multiple websites that detail the step-by-step process of accessing the board, examining the damage, and replacing it if necessary. Depending on the extent of the problem, simply buying a new inverter is often easier than trying to repair old problems. Many computer retailers sell this piece, and in most places it’s not very expensive. It’s often recommended that users check the warranty information on the computer before making any repairs or replacements, though; if the laptop still has a valid warranty, the manufacturer will usually take care of the repair at no cost.