What is pixel pitch?
Once you determine your viewing distance, you can select the optimal pixel pitch for your specific application. An LED screen is made up of an array of tiny LED chip clusters and pixel pitch is the distance in mm from the centre of one LED chip cluster (or pixel) to the next. The smaller the pitch, the higher the resolution and also the higher the cost for a given screen size.
How to choose the pixel pitch?
While you might be tempted to simply buy the highest resolution within your budget to display clear, crisp images, there’s a science behind choosing the ideal pixel pitch for your viewing conditions. There are several factors to consider when choosing the pixel pitch of your LED display, notably viewing distance, viewing angle, resolution, and the type of content you’ll be viewing.
Consider Viewing Distance and Viewing Angle
The viewing distance is the average distance between where you’ll be sitting or standing most of the time and the screen, taking into consideration whether you’ll be wall-mounting it or placing it on top of any supporting unit.
The 20°field of view shown in the image on the left is clearly too far. Fine details in most scenes are too small, it doesn’t deliver an immersive viewing experience. Look at the image on the right, which shows the same LED display but moved a bit closer so it fills up a 30°field of view. It’s much easier to see fine details in the image, which then delivers a more immersive viewing experience.
The Society of Motion Picture and Television Engineers recommends viewing at a distance where the screen fills up a minimum of 30°of your field of vision for a good experience. That’s a good baseline that works well for most setups, but depending on your specific needs and how you plan on using the LED display, you might want to go even closer. A 40° field of view is the recommended maximum for a more immersive viewing experience.
Multiplying the viewing distance by 0.6 will yield a screen size that will be close to a 30°field of view, while multiplying the viewing distance by 0.84 will get you a screen size close to a 40°field of view. Since these metrics are horizontal, the result will be the ideal screen width. Next you can calculate screen height to get the ideal screen size, taking into consideration also available space for installation, aspect ratio, and LED display module size.
The Best Screen Size Depends on the Content
With prices dropping on LED displays, one question often arises: whether you should prioritize size over performance. Should you get the larger but slightly worse resolution screen or get a smaller but better resolution screen? The answer isn’t so straightforward. It’s important to choose the LED display that fits your viewing environment and get the best quality within your budget.
What you watch on your LED display will determine the optimal size and viewing distance. If you intend to watch HD videos, then we have found that a screen size with 40° field of view is more enjoyable. If you’re watching images and normal videos in a limited office space where aesthetics are a concern, then you may choose a screen size that will have 40° field of view or maybe even less.
You also should consider the type of viewing experience you prefer, which is a subjective decision. One of the most common complaints we hear from people after choosing a LED display is that a larger LED display would have been better. It’s not very common to hear people admit that they wish they had chosen a smaller LED display.
Optimal Viewing Distance for Various pixel pitch
Visual acuity distance is the point at which the eye can ‘resolve’ or distinguish individual details in an image. Experts suggest that someone with 20/20 vision can distinguish details that are 1/60th of a degree apart. Our ability to resolve details is determined not only by visual acuity but also by distance. At a certain distance, depending on your eyesight, your eyes won’t be able to distinguish every detail. So, if you are too far, your eyes won’t be able to resolve the image, but if you are too close, that image will appear pixelated. For lower resolutions, you have to view a bit further than preferable to not notice the pixels, while higher resolutions give you more freedom.
Everyone’s eyesight is a little different, so visual acuity isn’t the best way to figure out the best viewing distance. The average optimal viewing distance for the pixel pitch can help you determine a screen setup that takes full advantage of your LED display’s resolution.
The chart below shows the average optimal viewing distances for various pixel pitch
Other Factors to Consider When Choosing a LED display
There are a few other factors that you may wish to consider when selecting a pixel pitch and screen size.
- The first is aesthetics.
- Safety should also be considered. When placing the LED display on a wall, be sure to consider the wall size, weight and the wall’s weight limit.
- Consider the best height to mount your LED display, which can determine how large the screen can be. The height of the display may change the room’s aesthetics.
- Finally, the budget is an important factor. Larger screens and higher resolution displays cost more.