Mobile screen resolution terminology: logical resolution and physical resolution

Mobile screen resolution terminology: logical resolution and physical resolutionReleased: May 13, 2015 by admin

Recently, in the group of 25 schools, several small partners were asked about the resolution size of the smartphone screen. I also want to be sure that most of the small partners in mobile development are not particularly aware of what the logical resolution and physical resolution are.

Today, 25 of the school's old tan from a personal point of view and some geek's point of view, to give you literacy.

As we all know, mobile phone screen resolution is one of the important parameters.

We all know that mobile device screen size is very large, fragmented seriously. Especially Android, you will hear many kinds of resolutions: 480x800, 480x854, 540x960, 720x1280, 1080x1920, but also the legendary 2K screen, 4K, 5k and so on. The fragmentation of the iphone has intensified in recent years: 640x960, 640x1136, 750x1334, 1242x2208.

What is the logical resolution and the physical resolution of today's focus with everyone?

explanation One: as the saying goes, the physical resolution is supported by hardware, and the logical resolution is what the software can achieve.

Let's take a look at the size resolution table for the iOS client:

Physical size refers to the actual size of the screen. Large screens must also be equipped with high resolution, that is, how many pixels can be displayed in this size, and the more pixels are displayed, the more natural the room can be.

EXPLANATION two: As the corresponding English words.

640*960, 640*1136, etc. are all physical dimensions or physical resolution.

The following 320*480, 320*568, etc. are logical resolutions or logical dimensions.

explanation Three: from another point of view: The resolution is the total number of pixels on the screen, horizontal and vertical.

If we design by the unit PX, can be said to be the physical resolution size.

If we design with a unit PT, it can be said that the logical resolution size.

Take the iphone 6 Plus for detailed analysis:

1, the iphone 6 Plus logical point resolution with 360x640, nor can not, that is, the above chart in the iPhone 6+ (b) scheme, then scale with @3x, the final pixel resolution 360x[email protected] Exactly the 1080x1920, perfect 1:1 mapping, without scaling, but the downside is that the logic PT resolution 360x640 of the iphone 6 Plus is lower than the 375x667 of the iphone 6, God forbid, a plus big screen, though fine, But the actual content that can be displayed is less than the IPhone 6. Completely incompatible with bigger than bigger.

An analogy is: in the case of the same font size, iphone 6 If the line shows 25 words, and iphone 6 Plus by this logic PT scheme, a row will only display 24 words.

2, that if the logical point resolution with 540x960, that is, the chart of the IPhone 6+ (c) , scale in the old @2x, the final pixel resolution 540x[email protected] is not exactly 1080x1920, Also perfect 1:1 mapping, no scaling, no need to do @3x material, and the advantages of this scheme is also obvious: the PT area is twice times the size of the IPhone 6 (540x960 = 375x667x 2), so that the screen can display more content, but this solution is more obvious shortcomings: The actual physical area of all IOS UI element dimensions on the screen is suddenly smaller, such as the physical height of the tab bar or navigation bar button is only 81.5% of the original,

Click on the area only IPhone 6 0.815*0.815=66.4%, the user click on the difficult, not always apple to consider touch finger operation, for <= iphone 6 to do a set of design specifications for the iphone 6 Plus another set of design specifications.

Mobile screen resolution terminology: logical resolution and physical resolution