You must master some common sense about mobile phone screen!

With the development of science and technology, mobile phones are no longer a simple mobile communication tool, but a device that integrates personal work, life and entertainment. The screen is the most intuitive part when using the phone. The quality of a screen directly affects the overall experience of the phone.

Now let me popularize the knowledge you should know about the mobile phone screen for everyone. Next time you buy a mobile phone, you can buy a product with a better screen.


1： Screen fineness


I think an important factor that determines the quality of the mobile phone screen is whether the screen display effect is fine enough and whether there is a sense of granularity. This indicator is determined by screen resolution, pixel arrangement and screen size. Among them, the physical quantity that determines this factor is the PPI of equivalent RGB arrangement.


For mobile phones:


1. When the PPI of the equivalent RGB array is lower than 300, the fineness of this screen is poor;


2. When the PPI of the equivalent RGB array is 300-325, the fineness of this screen is poor;


3. When the PPI of the equivalent RGB array is 326-350, the screen fineness is qualified;


4. When the PPI of the equivalent RGB array is 351-400, the screen is fine;


5. When the PPI of the equivalent RGB array is above 400, the fineness of this screen is good.


With the iPhone 11 Pro, its resolution is 2436 * 1125, the pixel arrangement is diamond arrangement, the screen size is 5.8 inches, and the PPI of the equivalent RGB arrangement is 374. It can be seen that this screen has good fineness.


Let me introduce these three indicators.


Screen resolution: The screen resolution is the number of pixels displayed on the screen. The resolution of 3840 * 2160 means 3840 pixels in the horizontal direction and 2160 pixels in the vertical direction. When the screen size is the same, the higher the resolution, the more delicate and delicate the display effect.


Pixel arrangement: The current pixel arrangement methods mainly include standard RGB arrangement, diamond arrangement, Zhou Dongyu arrangement, RGBRGW arrangement, Delta arrangement, etc. Under the same resolution, the screen fineness of standard RGB array is the best, followed by diamond array, which is 81% of the standard RGB array, Zhou Dongyu array is 74% of the standard RGB array, RGBRGW array is 71% of the standard array, and Delta array is 67% of the standard array.


PPI of equivalent RGB arrangement: Due to the different arrangement of mobile phone screen pixels among manufacturers in recent years, the traditional PPI formula can no longer show the fineness of mobile phone screen. At this time, an equivalent RGB arranged PPI can be introduced to determine the screen fineness. The specific point calculation method is under the root sign (square of horizontal pixels+square of vertical pixels) * screen pixel arrangement conversion/screen size.


This calculation result can well reflect the screen fineness.


2： Gamut


Color gamut is a method of coding a color, which also refers to the sum of colors that can be produced by a technical system. In computer graphics processing, color gamut is a complete subset of colors. The most common application of color subsets is to accurately represent a given situation. For example, a given color space or the rendering range of an output device.


For mobile phones, the current mainstream color gamut is 100% DCI-P3, and 72% NTSC or 100% sRGB are low-end screens. A wider color gamut can display more colors, and a low color gamut screen will make the display dim.


3： Chromatic accuracy


Color accuracy is a measure of the accuracy of color restoration. It is generally expressed in JNCD. A good screen JNCD can be less than 0.5.


4： Maximum screen brightness


This indicator affects the HDR display effect and the display effect in outdoor sunlight. I think 1200nit excitation brightness can bring good HDR effect. In outdoor sunlight, 600nit brightness is the minimum standard to see the screen clearly.


5： Color depth


Color depth, also known as color bit depth, is a unit that uses bit numbers to represent the number of colors in a digital image. Generally speaking, the mobile phone screen is 8bit, and the Xiaomi 10 Premium commemorative edition is 10bit.


6： Refresh rate


The refresh rate is the number of frames displayed on the screen in one second. 60Hz is 60 frames per second, and 120Hz is 120 frames per second. The higher the refresh rate, the higher the display fluency.


7： Screen luminous substrate


This item is mainly aimed at Samsung's AMOLED screen. Both the flagship and Apple's mobile phones use high-end M-series base materials, while domestic phones use mainstream E-series base materials. Ranking from good to bad is M10, M9, E3 and E2.


8： Others


At present, for mobile phone screens, most of the good screens are used in some foreign brands, such as Samsung, Apple, Sony, LG and Google.


For domestic brands, some screen suppliers will get stuck and can't get the best screen. For example, the AMOLED screen of the M-series base material used by Samsung itself is only used by Samsung and Apple. The Samsung AMOLED screen with the best domestic function is the E3 base material. Although we are trying to catch up with the domestic screen, it is still far from the international first-class level.