Remember the magic opening video of Samsung Note 2 conference, Note 2 A major function is S Pen You must be very curious about the control ability of S Pen. In addition, how does the button of S Pen work? Is there power supply inside S Pen? How to charge the S-Pen. Let's see how the magic of S Pen's air separation control is realized.

On MWC, Samsung Officially released Note 8.0, a new function of this tablet can directly click and control the virtual capacitor button below through S Pen. In addition, the relevant technology of S-Pen was actually developed by Wacom, and Samsung recently bought 5% of the shares of Wacom. It can also be seen that Samsung is paying more and more attention to the development prospects of the S Pen stylus.

Here is a quick introduction to the video, but I still suggest that you can read the full text in more detail if you are not in a hurry.

How does the S-Pen supply power?

If you have used Galaxy Note 2 It is known that S Pen has a button that can interact with the phone. Press the button to capture the screen. So there is no doubt that S Pen needs power, so you should agree? Of course, what we quickly think of is that the S Pen has a rechargeable power supply inside. Well, here's the problem. We want to further explore how the charging of S Pen is realized.

The answer is that the S Pen power supply is charged wirelessly through the screen. There is a circuit board at the bottom of the screen. When using the S Pen (that is, when the pen is close to the screen), the circuit board at the bottom forms a magnetic field at the top of the screen through electromagnetic induction to charge the S Pen.

How to verify it. The metal box can shield the electromagnetic field statically. So we thought that if we put metal on the cushion ring around the S Pen to shield the electromagnetic field, would the S Pen fail immediately? The answer is: Yes!

In fact, everything has nothing to do with the screen!

▲ In fact, the function of S Pen has nothing to do with the screen. The key is the electric board below.

Yes, in fact, the screen is not helpful for the functions implemented by S Pen, including writing notes. Draw pictures, etc. How does S-Pen interact with mobile phones? So as to realize the functions of drawing and writing. In fact, it is still a circuit board at the bottom of the screen. The circuit board will form an electromagnetic field at the top of the screen. When S Pen is in an appropriate position at the top of the screen. In addition to charging the phone to support functions such as the S Pen button, this electromagnetic field will also detect and calculate the position of S Pen in the electromagnetic field. When S-Pen touches the screen, the pen tip will be held back and retracted towards the pen barrel to start the relevant device, and then you can draw pictures on the screen.

If you have S Pen at hand, you can also try it yourself. Press the pen tip down, and the pen and the screen are separated by an appropriate distance (almost the sensing distance). Move the pen tip to draw lines on the screen. If the pen tip pops up automatically, it can only display a small light point on the screen. Well, here comes the question. What should we do to achieve pressure sensing reaction?

About pressure sensing

The pressure response has nothing to do with the screen! Yes, S Pen has completed the task of pressure sensing reaction (the screen is covered with protective glass). Here, measure the pressure sensing of S Pen. The pressure sense is detected by touching the internal components of the S Pen with the pen tip. In fact, it is difficult to experience the 1024 level pressure sense claimed by Samsung during use. The thickness is not so obvious.

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