Decrypt the past and present life of multi-touch technology

When we first met Apple iPhone many years ago, I believe that many people like me, the first thing that amazed at it was the way it had never seen before. I couldn't help being surprised and curious: can mobile phones still play like this? And Apple iPhone is also the "initiator" leading the touch screen era. Smart phones begin to enter the touch screen era, and Apple iPhone plays an irreplaceable and important leading role in the development of smart phones.
At that time, iPhone was widely concerned by people, not only because of its simple and trendy interface, but also because of those fancy control methods, which were also attributed to multi-touch technology. Multi-touch technology has also developed rapidly in several years, and with the rapid popularization in the application of smart phones, multi-touch technology is definitely one of the heroes of user experience; it is also because of its application, only then can we have the honor to see such a variety of interface control methods.
Resistance screen and capacitance screen:
Multi-touch technology makes touch-screen mobile phones quickly replace the dominant position of physical key-press mobile phones, which forcibly squeezes the key-press mobile phones off the platform. This is not only because people have a new understanding of mobile phone manipulation, at the same time, it is also closely related to the development of mobile phone screen technology.
Before we know the multi-touch technology, we need to know that there are mainly two types of mobile phone screens, one is resistance screen and the other is capacitance screen.
Resistance screen:
Simply put, it is to exert pressure on the screen, generate electric current, and then the screen makes recognition and reaction. The characteristic of this screen is that no matter the ear presses the screen with any object, the screen will react.
The representative applications are the early Windows mobilephone, the Touch model with stylus pen, the early touch screen model of Nokia and so on.
Capacitive screen:
The capacitive screen is operated by electrostatic induction. Simply speaking, the screen does not need to press the screen. The screen generates the current signal by sensing the static electricity of fingers and then reacts. Capacitive screen is also the most widely used mainstream screen at present. Structurally, the capacitive screen is a layer of transparent special metal conductive substance stacked on the display panel. When the finger touches the metal layer, the capacitance of the contact will change, due to the electric field of human body, a small magnetic field is formed between the user and the touch screen surface, and the contact signal is analyzed by the sensor after the electric current is generated.
The characteristics of the capacitive screen make it do not need to rely on pressure to achieve relevant operations, so it is superior to the resistance screen in response speed, with high sensitivity and easy to timely convey and feedback the user's operations. The resistance screen needs pressure to be operated, the response speed is slightly slower, and the sensitivity is slightly worse, so it is not as easy to operate as the capacitor screen.
Although the resistance screen has high precision, its response is not sensitive enough, and the support for multi-touch on the resistance screen is very limited, so the control is relatively simple, and now it has basically faded out of the intelligent platform. On the contrary, capacitive screen is more suitable for multi-touch technology, and its durability is much higher than that of "soft" resistive screen.
What exactly is multi-touch technology?
The concept of Multi-Touch:
The early touch screen has not been applied to multi-touch technology. The screen can only judge one touch point at a time, which means we can only use one finger to operate. If more than two points on the screen are touched at the same time, the correct response cannot be made.
For example, ATM, which is often used in our life, uses a screen that can only recognize single-point manipulation.
However, after the multi-touch technology is integrated, the screen's response to the task will be divided into two aspects: one is to collect the signals generated by multi-touch at the same time, the second is to judge the meaning of each signal and make correct analysis and response, so as to realize the simultaneous clicking and touching actions of the five fingers of the screen.
Structure and core technology:
The mainstream mobile phone screens we use now all support multi-touch, and its principle is to add a transparent touch panel above the LCD panel, this touchpad is used to detect multi-touch at different positions and recognize the signal generated by each point at the same time. The core of multi-touch technology is this technology, namely, the suppressed internal total reflection technology.
Origin, Development and significance:
As early as 1984, it was also because of Steve Jobs's creativity and persistence of "replacing keyboard with mouse" that the mouse played an important role in the communication between computers and people. In 2007, Apple and Microsoft both published products and plans for the application of multi-touch technology, which made the technology enter the mainstream application. In the same year, Apple also got the patent of multi-touch technology and began to apply this technology to mobile phone products. Steve Jobs ceremoniously launched Apple's first mobile phone product iPhone.
Jobs thought that the smart phones at that time were not humanized, because 40% of the user interfaces of these phones were occupied by keyboards, and the buttons were fixed and immutable. If you cancel these keyboards, you can get a huge screen. Therefore, the revolutionary significance of iPhone lies in the user interface and multi-touch technology.
I have to say the digression: the relationship between the TouchPad and the thickness of the mobile phone body
With the upgrading of users' products and aesthetic demands, the industrial design of smart phones is also developing continuously, and the screen is just one of them, usually, we may pay more attention to which panel has better display effect, but ignore that the size of the body is directly related to the technology of the touch panel.
For example, Samsung's SuperAMOLED screen. The structure of AMOLED screen is mainly divided into three layers: AMOLED liquid crystal panel, TouchScreenPanel and outer glass protective layer.
SuperAMOLED further improved the construction mode of the touchpad, integrating the display drive unit and the touchpad on the AMOLED liquid crystal panel. Different from the current practice that the panels of other mobile phones must be built with an independent layer to place the touch sensor, the SuperAMOLED panel is thinner, unlike AMOLED, which also needs the touch sensing layer TSP and the air layer AirGap, it not only increases the sensitivity of operation, but also contributes to reducing the thickness of the fuselage.
What does multi-touch bring us?
The development of capacitive screen and multi-touch technology not only brings us a new way of screen control, but also enriches the experience of human-computer interaction. People do not simply click with their fingers, but add more sliding, dragging, multi-directional scaling and so on. It is also because of this that mobile phone products can provide more operation modes in the interface, bringing people a sense of freshness in vision and experience.
The first time I saw multi-touch was also on Apple's iPhone. When browsing web pages or photos, I often need to zoom in a certain area to see clearly. The iPhone took the lead in using double-finger touch to zoom in.
Double-finger zoom function is the most familiar multi-touch application. With multi-touch technology, how to apply it can be infinitely expanded through infinite imagination. Developers can apply multi-touch to many aspects and constantly innovate new ways of playing, such as the gesture function on mobile phones and tablets. By using different numbers of fingers and different sliding directions, you can complete different operations or call out different interfaces.
Two-point touch? Five touch? Ten touch?
The application of multi-touch is not only reflected in the interface operation of daily functions, but also the game experience, which makes it a reality for us to play the piano on "glass. When it comes to games, we have to mention that not all the mobile phones we use now use the same touch technology.
Due to the different positioning and cost of mobile phone products, the multi-touch functions supported by different product screens are also different. We often see in the evaluation: the screen of this machine supports two-point touch at most, and the screen of this machine supports five-point touch at most, etc. So far, the upper limit of the screen of mobile phone products is ten-point touch. So what is the difference between the screens with different upper limit of contacts? In fact, if you understand the concept of multi-touch, it is easy to understand.
As we said above, the higher the upper limit is, the higher the possibility that the screen of the product can recognize more contact signals at the same time and enrich the interface control mode is. In addition, the most intuitive embodiment is in the aspect of games. Some flying shooting games require us to control the direction of the plane with our fingers, and at the same time, we also need to click on the switch of weapons and so on as needed.
There are also more mainstream action shooting games, generally using the left hand to control forward, backward and left-right translation, the right hand to control the angle of view direction and action instructions, weapon switching and other operations, some games will also be specially set up to require multiple fingers to slide in different directions to complete the action. Such a complicated game mode certainly needs the support of multi-touch technology.
Suppose we use a mobile phone that only supports two-point touch to play this kind of game. When we put two fingers on the screen at the same time and need another operation of the third point, the screen cannot react, compared with screens that support more multi-touch, the game's control experience is completely different.
The same is true when we use mobile phones for daily operation. We will feel that the operation process will be smoother when we support screens with more contacts, on the contrary, mobile phone screens that only support two-point touch tend to have some delay phenomena. However, the number of contacts supported also reflects the positioning of this product. Flagship models are generally 10-touch, mainstream models are generally 5-touch, and relatively low-end entry models are mostly 2-touch, there are exceptions, but it is extremely rare.
Therefore, for a flagship model, running these large games is also the embodiment of hardware quality itself. Meanwhile, the sensitivity and contact support of screen touch are also very important.
Summary:
Science and technology really influence our life deeply. Looking back at the upgrading of mobile phone products, from small screen to large screen, from black and white screen to color screen, from no touch screen to full touch screen, mobile phone has become a window of small world. Constantly changing and various operation modes have greatly increased the fun of our use, and the operation has become richer and simpler. We only need to move our fingers to know and feel the world, of course, we must finally thank the multi-touch technology, because it enabled the touch-screen mobile phone to bring down the powerful Symbian button smart phone.