As you know, on the touch screen mobile phone, we usually use finger operation, also can use pen to operate at the same time, but you will find that if you want to write on phone screen, found the line of words are very thick, the precision of the stroke control is very poor, if make a line for the screen launch, or the words written in the space of an article, the basic is impossible.There are two commonly used touch screens on mobile phones, capacitive touch screen and resistive touch screen. The main differences are as follows:
A: resistive touch screen
The price is very cheap, the accuracy can reach the accuracy of a single pixel, which can be operated by fingers, fingernails, stylus and so on.However, it is soft and prone to scratches. Due to the extra screen layer, it performs very poorly in the sunlight with low visibility.
Two: capacitive touch screen
It's expensive, and the idea is to use the electrical current generated by contact with the screen to locate it, so you can operate it with your finger, but not with a non-biological pen like a fingernail.In addition, the precision of the capacitive touch screen can reach several pixels in theory, but the effective range is about 1 square centimeter in practice.Thus, capacitive touch screens are unlikely to be able to recognize handwriting, let alone draw lines.A typical application on an e-reader is the small screen of the T61. You will find that you can't operate it with nails, pens, etc., but you can operate it with your fingers.
Between resistive touch screens and capacitive touch screens, more and more devices have chosen to use capacitive touch screens.The iphone, for example, and most android phones use capacitive touch screens.Because of the way these two screens work, they are not suitable for e-readers and are difficult to install on e-ink screens.So the handwritten e-ink screens are touch sensitive touch screens.
Three: electromagnetic induction touch screen
The basic principle of electromagnetic induction touch screen is to identify the magnetic field changes generated by the electromagnetic pen operation process and the inductor under the panel, the electromagnetic pen is the signal transmitter (transceiver), the antenna plate is the signal receiver, the magnetic flux changes when approaching the induction, and the position points are defined by calculation.Almost all of the electromagnetic touch panel market is dominated by Japanese Wacom. Due to the high cost, the electromagnetic touch panel has the advantages of light transmittance, high resolution, sensitive response, z-axis induction ability, and is suitable for drawing, handwriting recognition, etc., without direct contact with the screen.The precision of the electromagnetic induction pen, handwriting recognition and so on are very suitable for scribing, annotating and taking notes in the text gap, which is the main reason for e-readers to use it.And the electromagnetic touch control module has flexible special, can match the software display, the disadvantage is that it relies on the handwritten pen electromagnetic emission to locate, the operation must use a pen.Therefore, the current e-reader products using e-ink screen are electromagnetic induction type touch, which cannot be operated by hand.
Four: future development direction
The industry is also aware of the problem of handwritten touch on the e-ink screen and is conducting some research on finger touch on the e-ink screen.For example, can you combine a resistive touch screen with an e-ink screen?In the future development direction of pvi, the touch screen integration on e-ink screen is a priority research direction of pvi.
How do you tell the difference?Very simple, you can use your fingers, but with nails, toothpicks, pens and other non-biological biological can not operate, is the capacitive touch screen.Finger, nail, toothpick, branch, etc. Can be operated, is a resistive touch screen.Can use electromagnetism pen to operate only, cannot use finger, toothpick, the hard thing such as branch operates, it is electromagnetism induction screen.