Skip to main content

Touch Screen Technology – Definition, Working, Types

Image
By



Touch screen technology is the direct manipulation type gesture based technology. Direct manipulation is the ability to manipulate digital world inside a screen. A Touch screen is an electronic visual display capable of detecting and locating a touch over its display area. This is generally referred to as touching the display of the device with a finger or hand. This technology is most widely used in computers, user interactive machines, smart phones, tablets etc to replace most functions of the mouse and keyboard.
Touch screen technology has been around for a number of years but advanced touch screen technology has come on in leaps and bounds recently. Companies are including this technology into more of their products. The three most common touch screen technologies include resistive, capacitive and SAW (surface acoustic wave). Most of low end touch screen devices contain on a standard printed circuit plug-in board and are used on SPI protocol. The system has two parts, namely; hardware and software. The hardware architecture consists of a stand-alone embedded system using an  8-bit microcontroller,  several type of interface and driver circuits. The system software driver is developed using an interactive C programming language.

Types of Touch Screen Technology:

The Touch screen is a 2-dimensional sensing device made of 2 sheets of material separated by spacers. There are four main touch screen technologies: Resistive, Capacitive, Surface Acoustical wave (SAW) and infrared (IR).
Resistive:
Resistive touch screen is composed of a flexible top layer made of polythene and a rigid bottom layer made of glass separated by insulating dots, attached to a touch screen controller. Resistive touch screen panels are more affordable but offering only 75% of light monitor and the layer can be damaged by sharp objects. Resistive touch screen is further divided into 4-, 5-, 6-, 7-, 8- wired resistive touch screen. The construction design of all these modules is similar but there is a major distinction in each of its method to determine the coordinates of touch.
Capacitive:
A capacitive touch screen panel is coated with a material that stores electrical charges. The capacitive systems can transmit up to 90% of light from the monitor. It is divided into two categories. In Surface-capacitive technology only one side of the insulator is coated with a conducting layer.
Whenever a human finger touches the screen, conduction of electric charges occurs over the uncoated layer which results in the formation of dynamic capacitor. The controller then detects the position of touch by measuring the change in capacitance at the four corners of the screen.
In projected capacitive technology, the conductive layer (Indium Tin Oxide) is etched to form a grid of multiple horizontal and vertical electrodes. It involves sensing along both the X and Y axis using clearly etched ITO pattern. For increasing the accuracy of the system, the projective screen contains a sensor at every interaction of the row and column.
Infrared:
In infrared touch screen technology, an array of X and Y axis is fitted with pairs of IR Leds and photo detectors. Photo detectors will detect any image in the pattern of light emitted by the Leds whenever the user touches the screen.
Surface Acoustic wave:
The surface acoustic wave technology contains two transducers placed along X-axis and Y-axis of the monitor’s glass plate along with some reflectors. When the screen is touched, the waves are absorbed and a touch is detected at that point. These reflectors reflect all electrical signals sent from one transducer to another. This technology provides excellent through put and quality.

Components and working of touch screen:

A basic touch screen is having a touch sensor, a controller, and a software driver as three main components. The touch screen is needed to be combined with a display and a PC to make a touch screen system.
Touch sensor:
The sensor generally has an electrical current or signal going through it and touching the screen causes a change in the signal. This change is used to determine the location of the touch of the screen.
Controller:
A controller will be connected between touch sensor and PC. It takes information from sensor and translates it for understanding of PC. The controller determines what type of connection is needed.
Software driver:
It allows computer and touch screen to work together. It tells OS how to interact the touch event information that is sent from the controller.The touch screen is one of the simplest PC interfaces to use, for larger number of applications. A touch screen is useful for easily accessing the information by simply touching the display screen. The touch screen device system is useful in ranging from industrial process control to home automation.
At the transmission end using a touch screen control unit, some directions will send to the robot for moving into a specific direction like forward, backward, rotating left and rotating right. At the receiving end four motors are interfaced with the microcontroller. Two of them will be used for Arm and grip movement of the robot and other two are used for body movement.
Some remote operations can be done with touch screen technology using wireless communication for answering calls, locating and communicating with staff, and operating vehicles and robots. For this purpose RF communication or infrared communication may be used.
Labels:

Comments

Post a Comment

Popular posts from this blog

Team Work - Meaning and Tips for better Team Work

By
A single brain is not always capable of making key decisions on its own. To come up with an efficient solution, an individual requires the help and advice of others. A team is established when individuals get together on a common platform with the common goal of completing a task. To guarantee optimum compatibility, team members should ideally come from similar backgrounds and have a single aim. To provide their best, the team members must complement each other and function as a single unit in tight cooperation. "There is no I in Team Work," as the saying goes, and each member must put the needs of his team first. Personal interests must take a second seat. Any team's performance is directly proportionate to the relationship between its members and their combined efforts. What is the definition of teamwork? Teamwork is defined as the sum of each team member's efforts toward the fulfilment of the team's goal. In other words, any team's backbone is its ability t
Post a Comment
Read more

Scientists discover a new theory / The fundamental property of light – 150 years after Maxwell

By
Light plays a vital role in our everyday lives and technologies based on light are all around us. So we might expect that our understanding of light is pretty settled. But scientists have just uncovered a new fundamental property of light that gives new insight into the 150-year-old classical theory of electromagnetism and which could lead to applications manipulating light at the nanoscale. It is unusual for a pure-theory physics paper to make it into the journal Science. So when one does, it’s worth a closer look. In the new study, researchers bring together one of physics' most venerable set of equations – those of James Clerk’s Maxwell’s famous theory of light – with one of the hot topics in modern solid-state physics: the quantum spin Hall effect and topological insulators . To understand what the fuss is about, let’s first consider the behaviour of electrons in the quantum spin Hall effect. Electrons possess an intrinsic spin as if they were tiny spinning-tops,
Post a Comment
Read more

19 Types Of Content Writing Services For Your Business

By
  It’s hard to know which type of content writing service is the best for your business.  There are so many  different types of content writing services  out there that it’s easy to get confused. You end up wondering if you’re choosing the right one for you. In this post, we’ll get rid of this confusion, once and for all. I’m going to list out the different kinds of writing services you could use.  By the end of this article, you’ll know whether you need a copywriter, a content writer, or a social media marketer and how they can help you achieve your business goals. This post is also useful for writers who want to hone their writing skills in a specific area. Let’s dive in and learn what types of content writing services exist and when you should use them. (Bonus – if you want to  hire the top 1%  of writers, go to the bottom to learn how). Types of Content Writing Services As we go through the list of content writing services, you will find that many of them overlap. That’s perfectly
Post a Comment
Read more