A touchscreen is an input device normally layered on the top of an electronic visual display of an information processing system. When touching the image button on the screen, the touch feedback system of the screen will drive a variety of connecting devices based on pre-coding program to replace the mechanical pointing panel, and finally reveal lively video and audio effect via liquid crystal display panel.
Commonly known as "Soft screen". In electrical engineering, resistive touchscreens are touch-sensitive mobile phone displays composed of two flexible sheets coated with a resistive material and separated by an air gap or microdots. There are two different types of metallic layers. The first type is called Matrix, in which striped electrodes on substrates such as glass or plastic face each other. The second type is called Analogue which consists of transparent electrodes without any patterning facing each other. And Analogue touch screen includes five kinds:
- Four-Wire Resistive;
- Five-Wire Resistive
- Six- Wire Variation
- Seven-Wire Variation
- Eight-Wire Variation
Commonly known as "Hard screen". As opposed to the resistive touchscreen, the capacitive touchscreen makes use of the electrical properties of the human body. A capacitive screen is usually made of one insulating layer, such as glass, which is coated by a transparent conductive material on the inside. Since the human body is conductive, which means electricity can pass through it, the capacitive screen can use this conductivity as input. When you touch a capacitive touchscreen with your finger, you cause a change in the screen's electrical field. Capacitive touchscreen contains two main categories:
Finger touch and
- ITO Film: it includes bright and dull materials, which have many characters: anti-scratch, anti-newton, anti-reflection;
- ITO Glass: it contains common and reinforced (physical reinforce and chemical reinforce) glass.
- Finger touch/ Multi-touch
- Finger touch: A type of touch screen ( or other fixed surface ) that is optimized for operation by human finger, as opposed to a stylus.
- Multi-touch: The ability for a touch surface to respond to multiple finger touches at the same time, includes: two-touch, five-touch and ten-touch.
- TOUCH PANEL STRUCTURE
As the development of touch panel technology, the innovations of mobile phone screen never stop. The technology evolution goes through from common Glass+Glass (G+G) and Glass+Film (G+F), to OGS, On-cell and In-cell, which are the three most advanced mobile phone screens technologies till now. However, the development of touch panel would be toward diversification in the future.
- G + G: Tempered Glass + Glass
- G + P: Tempered Glass + PET (plastic cover structure)
G + F/G + F+ F: Tempered Glass + Film / Tempered Glass + Film + Film
OGS: OGS touch screen is a kind of electronic products protecting screen that made by depositing an Indium tin oxide(ITO, used as electrodes to sense touch) layer on the back of the cover glass and pattern it to create the electrodes. One glass works as protector glass and touch sensor at the same time. OGS screen integrates protector glass with touch panel layer.
- On-cell/In-cell: On-cell/In-cell technology refers to integrate touch panel and Liquid Crystal Display into a single-layer display. On-cell is to put the Indium tin oxide (ITO) touch panel on the glass layer of display panel; In-cell is to put the ITO touch panel under the glass layer of display panel and integrate with Liquid Crystal Display (LCD).
The comparison of G+G, G+P, G+F/G+F+F, OGS, On-cell and In-cell
|G+G||Tempered Glass+Sesor Glass||
High light transmittance;
|G+P||Tempered Glass+ PET||
Manipulation of the handle viscous
Light transmittance is poor
Not resistant to corrosion
Tempered Glass+Sesor Film
Tempered Glass+2sesor Film
Small quantity production;
Low touch sensitivity;
|OGS||One Glass Solution||
Structure more simple;
|Need to change tempered glass and touch panel at the same time if broken|
On the LCD panel with touch
|The uneven colors when touch|
Embed the touch panel
function into LCD pixels
Difficult to ensure that yield and