LCDs have been used for a while, for example in digital clocks and laptops. In recent years they have become a standard for desktop monitors. During the same time, LCDs have also conquered the TV market.
Flatscreen monitors are much thinner and lighter than CRT (cathode ray tube) monitors. They also require less energy, emit no electromagnetic radiation, and the technology enables clearer images, higher resolutions, and a flicker-free display, which is easier on the eyes.
These are only a few key arguments to finally replace the old CRT monitor. This article explains the various features of monitors in general and flatscreens in specific. It will help you understand what you should watch out for when buying a new LCD computer monitor.
The screen size is measured in inches, diagonally from the bottom left to the upper right corner of the display. Available sizes range from 15″ to 30″. The most common size for a desktop monitor today is 19″ to 22″, but it is not uncommon to buy larger sizes.
Bigger sizes usually means you will have more room on your desktop. You might finally be able to view multiple open windows in parallel. However, bigger monitors also take up more space on your desk and they tend to be more expensive.
Aspect ratio describes the relative number of horizontal to vertical pixels in a display. Standard CRT monitors were almost square with an aspect ratio of 4:3. Today, you will find widescreen monitors that have aspect ratios like movie theater screens, i.e. 16:9 or 16:10. 16:9 is also called HD (high definition).
If you’re watching DVDs on your computer, you can avoid the black bars across your screen with a widescreen display. Wide ratios are also the most convenient solution for viewing multiple windows in parallel. The only reasons to go with 4:3 is that you either prefer it for some reason or you don’t have sufficient space on your desk for a wider monitor.
Resolution is the number of pixels displayed horizontally and vertically. Due to the nature of LCD technology, flatscreens have only one optimized or native resolution. Hence, their native resolution describes the absolute number of pixels present horizontally and vertically.
Unlike CRT monitors, using a lower than native resolution on a flatscreen, leads to fuzzy images. Hence it is important to choose the right native resolution from the start as you can not change it, unless you accept a loss of image quality.
Higher resolutions mean sharper images, higher clarity, and more desktop space. This is perfect if you multitask or enjoy to watch movies on your computer. On the other hand, text become much smaller and harder to read. Thus a high resolution is to be avoided if your eyesight is less than perfect.
Crunch Gear has produced a great comparison chart of aspect ratios and available resolutions. Click the respective links for the article or the .
Contrast ratio describes the difference between the brightest white and the darkest black the LCD computer monitor can display. Higher contrast ratios equal whiter whites and blacker blacks, as well as a greater degree of gray values in between. The best contrast ratio you can get is 1,000 : 1.
Contrast ratio is a difficult topic. You cannot really compare the values between different manufacturers. Also, sometimes you will find the term dynamic contrast, which is not the same as contrast ratio and can be deceiving.
LCD monitors are illuminated by several backlights. Brightness is measured in candelas per square meter (cd/m2). A higher rating of at least 300 cd/m2, i.e. higher brightness, is to be desired if you want to watch movies or play games on your computer. For office work and browsing a lower rating of 200 – 250 cd/m2 is fine.
The higher the viewing angle, the better people who look at the monitor from the side will be able to see its display. Compared to CRTs, LCDs have a limited viewing angle. However, this feature is only interesting if you expect yourself or guests to look at your monitor with an angle. You can ignore it if you’re always going to sit straight in front of your monitor.
All this time I’ve only been talking about the display and the LCD technology. But a monitor is more than just a display. It needs to be connected to a computer and possibly other devices. Hence, you need to know what type of port you will need and then make sure the monitor has it. Most importantly, check which connector your video card supports.
Here is a brief overview of the most common ones:
The latest digital display interface, produced since 2008.
High-Definition Multimedia Interface, a digital audio/video interface produced since 2003.
Digital Video Interface, the first digital video interface. Produced to replace VGA since 1999.
Video Graphics Array, the old analog connector, first produced in 1987.
The image below shows the ports mentioned above. From left to right: DisplayPort (blue), HDMI (black), VGA (white), and DVI (white).
In addition to these you may find component video, S-video, and composite video connectors.
To summarize, you should first pick a desired size, aspect ratio, and resolution. These characteristics should meet your needs. In the next step you can compare all available models for further features, most importantly contrast ratio, brightness, and available ports. Finally, the price will decide which model you can afford.
What is the most important factor for you when buying an LCD computer monitor?