Perhaps one of the biggest surprises of the new Redmi K30 4/5G is its screen, which is double the average 60Hz refresh rate. This is something we've perhaps yet to really get an explanation for, why and how? Today, Redmi has finally summarised it for us in a big article, translated from Chinese, trying to write as authoritatively as possible on the subject.
The Large Screen Frame Update, 2020 will be a flagship trend. The Redmi K30 was recently released and comes fully equipped with a 120Hz refresh rate screen as standard. It can display 120 frames per second. What is 120Hz? What technology does it use? Can our eyes recognise it?
Why is a high-speed screen so useful?
In fact, the human eye is easily deceived. For example, the frame rate of current movies is mostly 24 FPS, i.e. 24 frames played back in 1 second, and each frame captures all the light information of the object's movement in 1/24 second, so the blurring of movement is very obvious.
The advantage of this is that you feel that the image is coherent, but the details of the movement are lost in 1/24 of a second.
This is not a big sacrifice for movies, but in the game almost every frame is a static image, displayed in real time. When it's displayed at 24 frames per second, you can feel the lack of motion, that FPS lag.
These big games can reach frame rates of up to 300 FPS, and PC monitor manufacturers have a range of extremely high update frequency monitors, which allow every moment of the moving image to be jam-free.
120 Hz screen and the underlying principle
In the mobile phone industry, the screen refresh rate is usually 60 Hz. A The Redmi K30 is one of the few mass-produced mobile phones to achieve 120 Hz. How do you do this?
You should know that the LCD liquid crystal display can independently control the voltage of each liquid crystal cell to change the brightness of the red, green and blue pixels to produce the right colours.
A refresh rate of 120 Hz means that the display time of each frame is about 8.3 ms, half the screen time of an average mobile phone.
To this end, the Redmi K30 screen driver chip has been upgraded with a circuit design that allows the chip area to be increased by 15% compared to a 60Hz screen, and the driving capacity increased by 27%.
In addition, when the voltage of the liquid crystal cell changes, it must increase from the reference voltage to the data voltage, which takes time proportional to the load on the circuit. The load applies to electronic components such as transistors and resistors in the circuit. By reducing the size of these components, the load can be reduced, the charge time of the liquid crystal battery can be shortened and a faster update can be achieved.
In addition, to achieve a thinner and lighter screen, the Redmi K30 uses full-cell lamination technology, with ITO (indium tin oxide) touch film placed under the top glass substrate of the display, allowing the screen and touchscreen to be combined. Two in one.
So what is the screen refresh rate of 120Hz compared to 60Hz?
You can observe the scrolling of a webpage by slowing down (sliding today's headlines) and slowing down the speed of the recording: the 60 Hz screen seems to dadogott and obfuscated, while the 120 Hz screen still slides sharply.
Can the human eye really detect such a high refresh rate?
But this comparison does not explain the problem because, after all, the human eye has no slow playback function. Can it actually detect 120 Hz fine motion? Some people think that screen refresh rates above 60 Hz cannot be distinguished by the human eye.
To answer these questions, we need to look at the "refresh rate" of the human eye.
The key to the light sensitivity of the human eye is rhodopsin, found in the membrane of the retina. When the rhodopsin experiences light, it rapidly absorbs photons, completes a series of photochemical reactions in the billionth of a second, generates bioelectric signals and then conducts them through the optic nerve to the cortex. It has little time to process these electrical signals, but the speed of response is still astonishing.
Az Egyesült Államok Légierője kísérletet végzett, amelyben a pilóta egy képernyőt figyelt, melyen gyorsan váltogattak a repülőgépek képeit. Néhány pilóta még a repülőgép modelljét is megkülönböztette, még akkor is, ha a repülőgép képe csak 1/220 másodpercig jelent meg, vagyis az emberi szem “frissítési gyakorisága” valójában jóval 120 Hz felett van.
In addition to watching videos and playing games, you can also experience the subtle sensation of 120Hz screen refresh rate in everyday activities such as switching between interfaces, opening apps and reading the news.
The Redmi K30 with superior performance optimisation, power consumption is not a problem: after 7 hours of video, gaming, shopping and news tests, this 120Hz refresh rate screen increased power consumption by only 5% compared to 60Hz.
Now answer the question at the beginning of the article. Do you really need a 120 Hz screen refresh? Is it what you really need in a full screen? Do you need that many rear cameras? Do you really need high camera pixels?
