Seminar Reporton

Z-Force Touch

Submitted By:-

CSE [B.TECH 5TH SEM]

HISTORY EVOLUTION:-BARNEY and Bent Stumpe, engineers from CERN, developed a transparent touch screen in the early 1970s and it was manufactured by CERN and put to use in 1973. This touch screen was based on Bent Stumpe's work at a television factory in the early 1960s.

The prototype x-y mutual capacitance touch screen developed at CERN in 1977 by Bent Stumpe, a Danish electronics engineer, for the control room of CERN’s accelerator SPS (Super Proton Synchrotron).

MOBILE TOUCH SCREEN TYPES

RESISTIVE

CAPACITIVE

INFRA REDRESISTIVEINFRA -

RED

CAPACITATIVE

RESISTIVE TOUCH SCREEN

These are the most widely used type of screens in mobile phones. They are resistant to water and dust, and you can touch them with a finger, a stylus, etc. However, they are not resistant to scratches, and what’s more, they become less efficient when they get one. They have a lifespan of about 35 million touches.

A resistive touch screen panel comprises several layers, the most important of which are two thin, transparent electrically-resistive layers separated by a thin space. These layers face each other with a thin gap between. The top screen (the screen that is touched) has a coating on the underside surface of the screen.

A major benefit of resistive touch technology is its low cost. Additionally, as only sufficient pressure is necessary for the touch to be sensed, they may be used with gloves on, or by using anything rigid as a finger/stylus substitute. Disadvantages include the need to press down, and a risk of damage by sharp objects. Resistive touch screens also suffer from poorer contrast, due to having additional reflections from the extra layer of material placed over the screen.

CAPACITATIVE

More expensive than resistive screens, these are resistant to water, dust and scratches, and have a longer lifespan. However, you can

only activate them with your fingers.

A capacitive touch screen panel consists of an insulator such as glass, coated with a transparent conductor . As the human body is also an electrical conductor, touching the surface of the screen results in a distortion of the screen's electrostatic field, measurable as a change in capacitance. Different technologies may be used to determine the location of the touch. The location is then sent to the controller for processing.

INFRA-RED

It works on a similar principle as that applied in the capacitative screens.The major difference is that in spite of using capacitors across the ends of the screen, infra red radiations are applied.

The most expensive of these three types, these are however the most resistant kind. The only disadvantage is that they are activated with warmth; so if your fingers are frozen in the winter, there is a good chance you may not be able to activate your phone.

Z-Force Touch ScreenNeonode has patented and commercialized the zForce® (an abbreviation for “zero force necessary”) touch technology, which was designed to overcome many of the limitations of today’s touch screens. The premise of the Company’s approach entails the projection of an infrared grid across an electronic display. As users tap, swipe, or write on the screen, zForce® detects the location of the touch based on the interruption in infrared light projecting across the screen, which translates to coordinates on the grid.

Neonode overcomes limitations of both resistive and capacitive screens with its zForce® technology—creating a next-generation touch surface that the Company believes can be more economical as well as higher performing than either of the main technologies in use today. Currently, projected-capacitance touch screens represent the mainstream technology for multi-touch interfaces. However, zForce® also enables the convenient multi-touch features of capacitive screens but at the cost structure of more affordable resistive technologies.

WORKING PRINCIPLE

Neonode’s controller projects a grid of infrared light beams across the display layer. Touch is detected as a finger or object interrupts (by obstructing or reflecting) the light beams projected across the screen surface, which identifies the X and Y coordinates of the touch. The zForce® infrared optical touch screen relies neither on pressure nor conduction, enabling consumers to use a Neonode touch screen barehanded or while wearing gloves, holding pens or styluses, etcetera.

The zForce Technology pulses an infrared light across the screen at a rate of up to 120 times a second so the grid is continuously refreshed. As the user’s fingers move across the screen, the grid’s coordinates where the screen is touched are converted into mathematical algorithms in a process that is unique to Neonode.

ADVANTAGES:-1. The power consumption is as low as 1mW at 100Hz. Battery life of tablet devices will benefit from such a new type of touch screen.

2. It is cheaper technology as compared to the resistive and capacitative touch screens.

3. . It does not use the electrical properties of the human body to track movement.

DISADVANTAGES:-

1. A raised bezel is placed around the screen.

2. 1ms response times are quite possible with this new technology and there is little to no lag.