Viewing Angle Check For Monitors

Many modern LCDs have a wider viewing angle and have achieved specifications of nearly 180° in both a vertical and horizontal direction. However, in many cases this just means the screen is 'visible' and the  display uniformity of the central and peripheral areas of the screen, or the level of chromatic change aren't taken into account. Generally, the steeper the angle from which the LCD screen is viewed, the more the contrast generally declines.

Even when viewed at a slight angle, it's important that the brightness and chromaticity is very uniform, and there is not much chromatic change. This becomes particularly important when you have a group of people all viewing the monitor at once as not all will be able to see the screen head-on. 

Most of the time the viewing angles given in the specifications aren't really very helpful but if you look to see what panel type the LCD uses, you'll have a better idea on how it performs.

IPS, VA and TN panels are available. IPS liquid crystal panels have the least change in brightness or chromaticity when the screen is viewed from an angle, and they are followed closely by VA panels. However, the cost-effective TN type lags far behind in terms of characteristic viewing angle changes in brightness and chromaticity. Simply viewing a screen with TN panels from a slightly different angle makes the coloration change dramatically, and the screen looks completely different according to whether it is viewed vertically or horizontally. According to EIZO, there are quite a few products with a 20-inch wide screen or larger where colours look different in the central and peripheral areas even when the screen is viewed straight on.
 

The display on an IPS panel	The display on a VA panel	The display on a TN panel
When viewed from an angle, the displayed content can be distinguished completely and the colours also show up really well.	Compared with the IPS panel the screen is a little whitish and the chromaticity has slipped, but it is a satisfactory viewing angle for actual use	There is a very clear difference from the IPS and VA panels. The display throughout the entire screen lacks uniformity and there is a yellow cast.

To check how well your monitor performs when viewed from a different angle you can use the gradation and monochrome images we used in our previous monitor check articles.

You need to ensure the image fills the screen then look at it straight on, checking that the brightness and colours are uniform. This means looking at the top, bottom, centre and both sides of the screen. Next, gradually adjust the angle from which you view the screen, checking the brightness and colour uniformity as you do. Feel free to complete this process with an actual photograph you've taken too as it's sometimes easier to see the differences in the display.

It's well worth completing this check in-store (if possible) to ensure the LCD display you are purchasing performs well at various viewing angles. 

The EIZO Test
When EIZO carried out this check on the FlexScan SX2462W the display performed extremely well and more information about this display and all the other monitors available in the EIZO range can be found on the EIZO website.