Display is an important parameter for modern-age devices and with the advent of technology, displays have become better, sharper and also more responsive than ever before. There are certain parameters on which the quality of display depends in addition to the panel type, which we have already explained here.
You must have often seen terms like HD, FHD, 4K, 90Hz and 16:9, 21:9, 19.5:9 written in the specifications of a smartphone, laptop, monitor or TV. So, what are all these terms and how do they affect the display quality and user experience?
Let’s start with the basics. The HD, FHD, QHD, UHD (4K) are resolutions. While the 16:9, 21:9 and 19.5:9 are aspect ratios.
What is display resolution
Before getting to the display resolution, it is important to understand a few other things — Pixels and PPI (pixels per inch).
- Pixels are the smallest element on the display. It is basically a dot on a display that combines together to create an image that you see. Understand this like a jigsaw puzzle where you combine multiple blocks to complete the image.
- PPI (pixels per inch) basically represents the pixel density of a display. It indicates the total number of pixels within a one-inch line. Higher pixel density means there are more pixels packed in a one-inch line which generally returns better image quality. But, it’s codependent on resolution and screen size.
Now, let’s talk about the resolution of a display. Simply put, the total number of pixels arranged in horizontal by vertical pixels is the resolution of the display. For example, an FHD display will have 1920×1080 pixels resolution. Similarly, an HD display will have 1280×720 pixels resolution.
The 1920 and 1280 denote the height of the display, while the 1080 and 720 denote width in landscape displays like laptops, monitors and TVs. Things get reversed in the case of smartphones because they feature portrait displays and here the 720 and 1080 represents height, while the 1280 and 1920 is the width of the display.
So, the display resolution is directly proportional to the quality of the display. In theory, better resolution results in better image quality.
Most modern smartphones today feature a display resolution that reads FHD+, HD+ and so on. What’s that ‘+’ in the name? Well, for that you’ll need to understand the relation between the aspect ratio, resolution and screen size.
The aspect ratio is the ratio of horizontal and vertical pixel counts. So, a 1920×1080 pixel resolution display has a 16:9 aspect ratio. Both are codependent. Change the aspect ratio, the resolution will change and vice versa.
Coming back to the ‘+’ resolutions that we see in modern smartphones. The removal of bezels led to taller screen sizes and that changed the aspect ratio of the smartphones. So, the FHD resolution became FHD+, HD became HD+. For instance, take the Redmi Note 10 Pro Max that features a 6.67-inch FHD+ display and in this case, the resolution measurement is 2400 x 1080 which transforms into a 20:9 aspect ratio. Similarly, some phones feature 19.5:9 or 18:9 aspect ratio displays depending upon the screen resolution and size of the display.
How does screen resolution and aspect ratio affect the display quality
Now, most people think that if a phone has a better panel, let’s say an AMOLED panel, then the display quality will naturally be good. That’s correct to an extent. But, the screen size, resolution and aspect ratio also plays an important role here.
We have already established the concept that the screen size, resolution and aspect ratio is codependent and higher PPI results in better image quality. So, if a 5-inch display has HD+ resolution with an 18:9 aspect ratio, then the PPI count of the phone will be less compared to the same size display with FHD+ resolution just because of the higher pixel density.
Also, higher resolution means more pixel density given the screen size is the same and so will be the image quality as it will have closer pixels to display which results in a sharper and clearer image.