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WHAT IS TO BE EXPLAINED..

INTRODUCTION TO THEINTRODUCTION TO THE

TECHNOLOGYTECHNOLOGY

HOW IT WORKS ?HOW IT WORKS ?

TOUCH SCREEN DIVERSITYTOUCH SCREEN DIVERSITY

CONTROLERS USEDCONTROLERS USEDAPPLICATIONSAPPLICATIONS

CLOSING THOUGHTSCLOSING THOUGHTS

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HOW DOES A TOUCHSCREEN WORK?

Main touch screen components:Main touch screen components:

Touch sensor

Controller

Software driver

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CONTROLLER

The controller is a

small PC card that

connects between the

touch sensor and the

PC. It takes

information from the

touch sensor and

translates it into

information that PC

can understand.

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SOFTWARE DRIVER

The driver is a software that allows the touch screen

and computer to work together. It tells the operating

system how to interpret the touch event information

that is sent from the controller.

Most touch screen drivers today are a mouse-

emulation type driver. This makes touching the

screen the same as clicking your mouse at the same

location on the screen.

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TOUCH SCREEN DIVERSITY

Resistive Touch screen

Surface wave Touch screen

Capacitive Touch screen*Surface capacitive

*Projected capacitive

Near Field Imaging Touch screen

Infrared Touch screen

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RESISTIVE TOUCH SCREEN

1. Polyester Film .

2. Top Resistive Layer.

3. Conductive Transparent Metal Coating.4. Bottom Resistive Layer .

5. Insulating Dots .

6. Glass Substrate

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Continued

Resistive touch screen monitor is composed of a flexibletop layer and a rigid bottom layer separated by insulating

dots, attached to a touch screen controller.

The inside surface of each of the two layers is coated with

a transparent metal oxide coating Pressing the flexible top sheet creates electrical contact

between the resistive layers, producing a switch closing in

the circuit.

The controller gets the alternating voltages between the

two layers and converts them into the digital X and Y

coordinates of the activated area.

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VS20UA CONTROLLER

Supply Voltage

5.0V DC

Maximum

Current

20mA (Pick)

Resolution

12-bit

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SURFACE WAVE TECHNOLOGY

It has a transmitting and receiving transducers for boththe X and Y axes.

The touchscreen controller sends a 5 MHz electrical signal

to the transmitting transducer, which converts the signalinto ultrasonic waves within the glass.

These waves are directed across the front surface of thetouchscreen by an array of reflectors.

Reflectors on the opposite side gather and direct thewaves to the receiving transducer, which reconverts theminto an electrical signala digital map of the touchscreen

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Continued When you touch the screen, you absorb a portion of

the wave traveling across it. The received signal is thencompared to the stored digital map, the changerecognized, and a coordinate calculated. . The digitizedcoordinates are transmitted to the computer forprocessing.

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2701RSU CONTROLLER

Voltaze

+5 VDC

Baud Rate

9600 (default) and 19200

Touch Resolution

12bit, size independent

Conversion Time

10 ms per coordinate set

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CAPACITIVE TOUCH SCREENS

Surface Capacitive

It has a an uniform conductive coating on a glasspanel.

During operation, electrodes around the panel'sedge evenly distribute a low voltage across theconductive layer & creates an uniform electricfield.

A finger touch draws current from each corner.

Then the controller measures the ratio of thecurrent flow from the corners and calculates thetouch location

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5000 RSU SERIAL CONTROLLER

Supply Voltage :

+5 V DC or +12V

Baud Rate

9600 (default) and 19200

Touch Resolution

12bit, size independent.

Conversion Time

Approximately 15 ms percoordinate set

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Projected Capacitive

Touch screen

3layers:-front and

back protective glass

provides optical and

strength enhancement

options & middle

layer consists of a

laminated sensor grid

of micro-fine wires

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Continued During a touch,

capacitance formsbetween thefinger and thesensor grid.

The embeddedserial controller inthe touch screencalculates touch

locationcoordinates andtransmits them tothe computer forprocessing.

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APPLICATIONS..

Public Information Displays:::Tourism displays, Trade show display

Customer Self-Services:::Stores, Restaurants, ATMs, Airline ticketterminals and Transportation hubs.

More uses...Digital jukeboxes, Computerized gaming, StudentRegistration systems, Multimedia softwares ,Scientific applications etc.

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Pros & ConsDirect pointing to the

objects.

Fast

Finger or pen is usable(No cable required)

No keyboard necessary

Suited to: novices,

application forinformation retrievaletc

Low precision by usingfinger

User has to sit orstand closer to thescreen

The screen may becovered more by usinghand

No direct activation tothe selected function

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