One of my obsessions when I analyze a telephone is fluency, but understood as something measurable in objective terms, not as the subjective perception of whether a mobile is moving well or not. With the arrival of the high refresh rate, a good leap was made in it, but there is a big bet that is going unnoticed: the sample rate. Little by little, manufacturers begin to increase the bet for the touch sampling rate, an unknown that can completely change the experience with a phone. The response speed of the panel depends largely on it, and some manufacturers are reaching record figures.
The sample rate vs the refresh rate
The refresh rate that has been talked about for so long in recent years refers to the frequency with which the screen updates the number of images it displays per second. In a matter of two years we have come to see 120Hz as mainstream, and the more frames the phone displays per second, the greater the sense of fluidity.
However, you have surely seen in a presentation that a mobile has a refresh rate at 120Hz and a touch sampling rate at 360Hz. The touch sample rate refers to how often the panel checks user interaction. In other words, how often the screen detects if we have our finger on it or not.
The panel latency largely depends on this sample rate, that is, how long it takes for the screen to react to our finger. Although we are talking about milliseconds here, when we are typing fast, playing with the mobile or scrolling, minimizing latency is key for an excellent experience.
The big bet on the sample rate
Little by little, manufacturers are reinforcing their commitment to the tactile sampling rate. A good example is the Lenovo Legion Phone Duel 2, with a touch sampling rate of 720 Hz. It is the same case of the Black Shark 4 Pro, with a 144 Hz refresh rate but a 720 Hz on-screen sampling.
We also have a high sampling rate in terminals designed for the general public, such as the Realme GT 2 Neo, with 600 Hz. In the case of Xiaomi, its Mi 11 Ultra has a 120 Hz refresh rate, but a touch sampling of 480 Hz. It is the same case of the S21 Ultra, with said 480 Hz in this superior model, but 240 Hz in the S21 +.
In other words, manufacturers are improving the response time of the screen significantly, although at the marketing level the refresh rate is more relevant than touch sampling. The way to go is long, and latency not only depends on this rate (the distance between screen and glass, the device’s own power, etc.), but little by little a path opens up that benefits users.
