History of the Touch Screen

It's like what do you know the history of the touch screen (touchscreen)? for the already well "thank God", for which I have not tried posting here ..!

In 1971, the first time "Touch Sensor" was developed by Doctor Sam Hurst (who in addition to drawing on the left) as well as an instructor at the University of Kentucky. These sensors are called "Elograph," and has been patented by the University of Kentucky Research Foundation. "Elograph" is not transparent like modern touchscreens, however elograph has become a significant milestone in touchscreen technology. In 1974 The real first touchscreen equipped with transparent surfaces was developed by Doctor Sam Hurst and Elographics. In 1977 Elographics developed and patented by a five-wire resistive technology, which is the most popular touchscreen technology used today. Touchscreens eventually become commonplace in everyday life. The company uses a touch screen kiosk system in the regulation of retail sales and tourism, sales center, ATM, and PDAs, where the stylus is sometimes used to manipulate the GUI and to enter data. Popularity of smart phones, PDAs, portable game consoles and various types of information appliances has boosted demand and acceptance of touchscreens. HP-150 from 1983 has become one of the computers in the world's earliest commercial touchscreen. Surely not have a touchscreen in a narrow sense, but it has a CRT tube Sony 9 "which is surrounded by infrared transmitters and receivers, which detect the position of each non-transparent objects on the screen. 

Initially originally touchscreens could only sense one point of contact at a time, and have little ability to sense how hard a person touches. Has now begun to change with commercialization with multi-touch technology. Tablet PCs was initiated by apple computer and followed by world famous brands others have made multi-touch touchscreen becomes the primary interface with the various capabilities that it provides.

Types of Touch Screen (touchscreen) 

System resistive screen is coated by a thin layer of colored metallic conductive and resistive to electrical signals. The purpose of the conductive layer is a layer that is easy to conduct electrical signals, while the resistive layer is a layer that holds an electrical current. These two layers are separated by a separator transparent spots, so that this layer must be separated from each other in normal circumstances. On the conductive layer is also in charge of electric current flowing as a stream occur referensi.Ketika second touch this layer will be forced to directly contact each other physically. Because of the contact between the conductive and resistive layers there will be interference with the reference electric current. The effects of these disorders on the conductive layer is going to change electrical currents in response to a touch event. Change the value of the reference current is then reported to the controller for the process further. 

Touch information was processed mathematically by the controller so as to produce an accurate coordinates and the position of the touch. Then the information is integrated with other programs so that it becomes an application easy to use. Screen with this technology has the highest image clarity by 75% only, so that the monitor will seem less clear. Touch sensors of this type are very vulnerable and weak to touch objects that are somewhat sharp. This technology will not be affected by other elements outside such as dust or water, but will respond to all touch about it, either using your fingers directly or using another object such as a stylus. It is used for industrial purposes in the world such as in factories, laboratories, and many more. Examples of HP who use resistive screens are Samsung Star, Sony Erricson W950.

Capacitive sistem have a wrapper layer that is the key of how it works, that is a wrapper which is capacitive in the entire surface. Touchscreen panel is equipped with a coating made ​​from indium tinoxide which could continue for an electric current is continuous, then directed to the sensor. This layer can utilize the capacitive nature of the hand or the human body, and therefore this layer is employed as a touch sensor in this type of touchscreen. When the layers are in normal status (without any touch of the hand), the sensor will be given an electric current value is used as reference. When your fingers touch the surface of this layer, then the reference value is changed because there are electric currents that change the entry to the sensor. Information from this incident in the form of electrical current will be received by the sensor to be transmitted to a controller. Position calculation process will start here. This calculation uses the position of the four points sudur touchscreen panel as a reference. When the results of the calculation is obtained, then the coordinates and the position of the touch can be designated in the know with the good. Finally, information from these positions will be integrated with other programs to run an application. 

The new capacitive touchscreen can work if it touches against him came from a conductive object such as a finger. Display screen has a clarity of up to about 90%, making it suitable for use in a variety of purposes interactions in the general public such as in restaurants, electronic kiosks, the location of Point Of Sales, etc.. Examples of HP that use capacitive screens are Samsung Corby touchscreen, the iPhone.

Teknologi touchscreen utilizes ultrasonic waves to detect events at the surface of the screen. Inside this touchscreen monitor, there are two transducers, sender and receiver of ultrasonic signals. Also equipped with a reflector which also serves as a deterrent so that ultrasonic waves remain on the monitor screen area. Both transducers are mounted in all four sides, two vertical and two horizontal. When it touched the touchscreen panel, there is a part of the wave is absorbed by touch, such as hindered by the hand, stylus, keyboard, and more. The touch had made changes in the waveform emitted. Changes in ultrasonic waves that occur later accepted by the receiver and translated into electrical pulses. Further information had been turned into a form of touch data to be forwarded to the controller for further processing. 

Data generated from this touch of course is data about the position of your hands that touch the ultrasonic signal. If this is carried out continuously and there are a lot of the ultrasonic wave sensor on the media it touches, so be a touchscreen device that you can use. This technology does not use a metallic coating material but rather a layer of glass, the appearance of the touchscreen display able to continue this kind of light up to 90 percent, making it much clearer and brighter than the Resistive touchscreen. Without the sensor layer also makes the touchscreen of this type become stronger and more durable because there will be no layers that can be damaged when the touch, when exposed to water, oil, dust, and more. 

Well, the downside is the performance of the touchscreen can be interrupted by elements such as dust, water, and other solid objects. There is very little dust or other object attached to it then touchsreen can detect it as a touch. Touchscreen type is suitable for use on computer training room, the room needs to display information in a very clear and sharp and the presentation in the room.