Touchscreen

Shopping on line can be easy, simple and save you lots of money. It can also take a lot of your time, frustrate you, and result in unwanted purchases. Now the same can be said for regular high street shopping, but with the vast opportunity presented by the Internet it will pay you to spend a few minutes reading this and understanding how to better optimize your Touchscreen shopping experience:

1. Compare - without doubt the biggest advantage that the Touchscreen offers shoppers today is the ability to compare thousands of Touchscreen at a time. This is a great thing, but not necessarily all the time! Too much can be daunting at times so take advantage of the great comparison sites and where possible let them do the hard work for you.

2. Research - if it has been said it will be on the internet. Ignorance is no longer a justifiable reason for buying the wrong thing. Take the time to research in detail everything that you could possible want to know about

3. Testimonials - don't know anybody that has bought a Touchscreen? Wrong! If the Touchscreen is good the internet will let you know. Use the Internet as a friend and get testimonials before you buy.

4. Questions - Got a question about Touchscreen then search the Forums, FAQ's, Blogs etc. Don't be afraid to ask .....

5. Reputation - Never heard of the company selling Touchscreen? Don't worry, no reason why you should know every company in the world, but you know someone that does! Use the internet to find out what people are saying about Touchscreen and build up a picture of their reputation for sales, returns, customer service, delivery etc.

6. Returns - still worried that even after all of the above your Touchscreen wont be what you want? Check out the returns policy. There is so much competition now that someone, somewhere is bound to offer the terms that you are comfortable with.

7. Feedback - happy with your Touchscreen then let people know, after all you are depending on others people input in your buying decision, so why not give a little back.

8. Security - check for the yellow padlock on the Touchscreen site before you buy, and the s after http:/ /i.e. https:// = a secure site

9. Contact - got a question about Touchscreen, or want to leave a comment then check out the sites contact page. Reputable companies have them and respond.

10. Payment - ready to pay for your Touchscreen, then use your credit card or PayPal! Be aware of companies that don't accept them, there may be genuine reasons but given the huge amount of choice you have when buying online there is no reason at all not to buy via credit card or PayPal.

Touchscreens are display overlays which have the ability to display and receive information on the same screen. The effect of such overlays allows a display to be used as an input device, removing the keyboard and/or the mouse as the primary input device for interacting with the display's content. Such displays can be attached to computers or, as terminals, to networks. Touchscreens also have assisted in recent changes in the design of personal digital assistant (PDA), satellite navigation and mobile phone devices, making these devices more usable.

Applications use the touchscreen as a primary controlling device, but other games use it as a secondary controlling deviceTouchscreens have become commonplace since the invention of the electronic touch interface in 1971 by Dr. Samuel C. Hurst. They have become familiar in retail settings, on point of sale systems, on automatic teller machines and on Personal digital assistant where a stylus is sometimes used to manipulate the GUI and to enter data. The popularity of smart phones, PDAs, portable game consoles and many types of information appliances is driving the demand for, and the acceptance of, touchscreens.

The HP-150 from 1983 was probably the world's earliest commercial touch screen computer. It actually does not have a touch screen in the strict sense, but a 9" Sony Cathode Ray Tube surrounded by infrared transmitters and receivers which detect the position of any Opaque object on the screen.

Touchscreens are popular in heavy industry and in other situations, such as museum displays or room automation, where keyboards and mouse do not allow a satisfactory, intuitive, rapid, or accurate interaction by the user with the display's content.

Historically, the touchscreen sensor and its accompanying controller-based firmware have been made available by a wide array of after-market system integrators and not by display, chip or motherboard manufacturers. With time, however, display manufacturers and System On Chip (SOC) manufacturers worldwide have acknowledged the trend toward acceptance of touchscreens as a highly desirable user interface component and have begun to integrate touchscreen functionality into the fundamental design of their products.

Technologies There are a number of types of touch screen technology:

Resistive A resistive touch screen panel is composed of several layers. The most important are two Thin-film deposition electrically conductive and resistive layers separated by thin space. When some object touches this kind of touch panel, the layers are connected at certain point; the panel then electrically acts similar to two voltage dividers with connected outputs. This causes a change in the electrical current which is registered as a touch event and sent to the controller for processing. When measuring press force, it is useful to add resistor dependent on force in this model -- between the dividers.A resistive touch panel output can consist of between four and eight wires. The positions of the conductive contacts in resistive layers differ depending on how many wires are used. When four wires are used, the contacts are placed on the left, right, top, and bottom sides. When five wires are used, the contacts are placed in the corners and on one plate. 4 wire resistive panels can estimate the area (and hence the pressure) of a touch based on calculations from the resistances. Resistive touch screen panels are generally more affordable but offer only 75% clarity (premium films and glass finishes allow transmissivity to approach 85%) and the layer can be damaged by sharp objects. Resistive touch screen panels are not affected by outside elements such as dust or water and are the type most commonly used today.

Surface Acoustic Wave (SAW): Surface Acoustic Wave technology uses ultrasonic waves that pass over the touch screen panel. When the panel is touched, a portion of the wave is absorbed. This change in the ultrasonic waves registers the position of the touch event and sends this information to the controller for processing. Surface wave touch screen panels can be damaged by outside elements. Contaminants on the surface can also interfere with the functionality of the touchscreen.

Capacitive A capacitor touch screen panel is coated with a material, typically indium tin oxide that conducts a continuous electrical current across the sensor. The sensor therefore exhibits a precisely controlled field of stored electrons in both the horizontal and vertical axes - it achieves capacitance. The human body is also an electrical device which has stored electrons and therefore also exhibits capacitance. When the sensor's 'normal' capacitance field (its reference state) is altered by another capacitance field, i.e., someone's finger, electronic circuits located at each corner of the panel measure the resultant 'distortion' in the sine wave characteristics of the reference field and send the information about the event to the controller for mathematical processing. Capacitive sensors can either be touched with a bare finger or with a conductive device being held by a bare hand. Capacitive touch screens are not affected by outside elements and have high clarity, but their complex signal processing electronics increase their cost.

Infrared An infrared touch screen panel employs one of two very different methodologies. One method used thermal induced changes of the surface resistance. This method was sometimes slow and required warm hands. Another method is an array of vertical and horizontal IR sensors that detected the interruption of a modulated light beam near the surface of the screen. IR touch screens have the most durable surfaces and are used in many military applications that require a touch panel display.

Strain Gauge In a strain gauge configuration the screen is spring mounted on the four corners and strain gauges are used to determine deflection when the screen is touched. This technology can also measure the Z-axis. Typically used in exposed public systems such as ticket machines due to their resistance to vandalism.

Optical Imaging A relatively-modern development in touch screen technology, two or more image sensors are placed around the edges (mostly the corners) of the screen. Infrared backlights are placed in the camera's field of view on the other sides of the screen. A touch shows up as a shadow and each pair of cameras can then be triangulated to locate the touch. This technology is growing in popularity, due to its scalability, versatility, and afford ability, especially for larger units.

Dispersive Signal Technology Introduced in 2002, this system uses sensors to detect the mechanical energy in the glass that occur due to a touch. Complex algorithms then interpret this information and provide the actual location of the touch. The technology claims to be unaffected by dust and other outside elements, including scratches. Since there is no need for additional elements on screen, it also claims to provide excellent optical clarity. Also, since mechanical vibrations are used to detect a touch event, any object can be used to generate these events, including fingers and styli.

Acoustic Pulse Recognition This system uses more than two piezoelectric transducers located at some positions of the screen to turn the mechanical energy of a touch (vibration) into an electronic signal. This signal is then converted into an audio file, and then compared to preexisting audio profile for every position on the screen. This system works without a grid of wires running through the screen, the touch screen itself is actually pure glass, giving it the optics and durability of the glass out of which it is made. It works with scratches and dust on the screen, and accuracy is very good. It does not need a conductive object to activate it. It is a major advantage for larger displays.

Frustrated Total Internal Reflection This optical system works by using the principle of total internal reflection to fill a refractive medium with light. When a finger or other soft object is pressed against the surface, the internal reflection light path is interrupted, making the light reflect outside of the medium and thus visible to a camera behind the medium.[http

Graphics tablet/screen hybrid technique: This new technique is definitionally not really a touchscreen, but has the same properties, in addition to having much more accuracy. It is a graphics tablet that incorporates an LCD into the tablet itself, allowing the user to draw directly "on" the display surface. It should not be mixed up with Tablet_pc#Hybrids.

Development Virtually all of the significant touchscreen technology patents were filed during the 1970s and 1980s and have expired. Touchscreen component manufacturing and product design are no longer encumbered by royalties or legalities with regard to patents and the manufacturing of touchscreen-enabled displays on all kinds of devices is widespread.

The development of multipoint touchscreens facilitated the tracking of more than one finger on the screen. Operations that are only possible with more than one finger are possible. These devices also allow multiple users to interact with the touchscreen simultaneously.

With the growing acceptance of many kinds of products with an integral touchscreen interface the marginal cost of touchscreen technology is routinely absorbed into the products that incorporate it and is effectively eliminated. As typically occurs with any technology, touchscreen hardware and software has sufficiently matured and been perfected over more than three decades to the point where its reliability is unassailable. As such, touchscreen displays are found today in airplanes, automobiles, gaming consoles, machine control systems, appliances and handheld display devices of every kind.

The ability to accurately point on the screen itself is taking yet another step with the emerging graphics tablet/screen hybrids.

Ergonomics and usage An ergonomic problem of touchscreens is their stress on human fingers when used for more than a few minutes at a time, since significant pressure can be required and the screen is non-flexible. This can be alleviated with the use of a pen or other device to add leverage, but the introduction of such items can sometimes be problematic depending on the desired use case (for example, public kiosks such as ATMs). Also, fine motor control is better achieved with a stylus, a finger being a rather broad and ambiguous point of contact with the screen.

Yet all of these ergonomic issues can be bypassed simply by using a different technique, provided that the user's fingernails are either short or sufficiently long. Rather than pressing with the soft skin of an outstretched fingertip, the finger is curled over, so that the top of the forward edge of a fingernail can be used instead. (The thumb is optionally used to provide support for the finger or for a long fingernail, from underneath.) The fingernail's hard, curved surface contacts the touchscreen at a single very small point. Therefore, much less finger pressure is needed, much greater precision is possible (approaching that of a stylus, with a little experience), much less skin oil is smeared onto the screen, and the fingernail can be silently moved across the screen with very little resistance, allowing for selecting text, moving windows, or drawing lines. (The human fingernail consists of keratin which has a hardness and smoothness similar to the tip of a stylus, and so will not typically scratch a touchscreen.) Alternately, very short stylus tips are available, which slip right onto the end of a finger; this increases visibility of the contact point with the screen.

When a touchscreen monitor is mounted vertically a condition often called "gorilla arm" can occur, because holding ones arm out horizontally for a prolonged time causes the arm to feel quite heavy (like a gorilla's).

Manufacturers of touchscreens

AMX LLC
Crestron Electronics
3M
Hitachi, Ltd.
iLight
Dynalite
Touch International
Elotouch
NextWindow

Notebook computer lines featuring touchscreens

Toughbook series by Panasonic
ST series Stylistic tablets from Fujitsu
P series and T series notebooks from Fujitsu
C1 series notebook from LG