Information input device, which is a screen that responds to touching it. There are many different types of touchscreens that work on different physical principles. But we will consider only those that are found in mobile phones and other portable equipment.
How resistive touch screens work
Resistive touch screens are of two types, four-wire and five-wire. Let's consider the principle of operation of each of the types separately.
Four-wire resistive shield
How the 4-wire resistive touchscreen works
The resistive touchscreen consists of a glass panel and a flexible plastic membrane. Both the panel and the membrane are coated with a resistive coating. The space between the glass and the membrane is filled with micro-insulators, which are evenly distributed over the active area of \u200b\u200bthe screen and reliably insulate conductive surfaces. When the screen is pressed, the panel and membrane are closed, and the controller using analog-to-digital converter registers the change in resistance and converts it to touch coordinates (X and Y). In general terms, the reading algorithm is as follows:
- A voltage of + 5V is applied to the upper electrode, the lower one is grounded. The left and right are short-circuited and the voltage across them is checked. This voltage corresponds to the Y-coordinate of the screen.
- Similarly, + 5V and "ground" are supplied to the left and right electrodes, the X-coordinate is read from the top and bottom.
5-wire resistive shield
The 5-wire shield is more reliable due to the fact that the resistive coating on the membrane is replaced by a conductive one (the 5-wire shield continues to work even with a cut membrane). The rear window has a resistive coating with four electrodes at the corners.
How the 5-wire resistive touchscreen works
Initially, all four electrodes are grounded, and the membrane is "pulled up" by a resistor to + 5V. Membrane voltage level is constantly monitored analog-to-digital converter... When nothing touches the touch screen, the voltage is 5 V.
As soon as the screen is pressed, the microprocessor senses the change in membrane voltage and begins to calculate the coordinates of the touch as follows:
- The two right electrodes are supplied with a voltage of + 5V, the left ones are grounded. The voltage on the screen corresponds to the X-coordinate.
- The Y-coordinate is read by connecting both top electrodes to + 5V and both bottom electrodes to ground.
How capacitive touch screens work
A capacitive (or surface-capacitive) screen takes advantage of the fact that a large object conducts alternating current.
How the capacitive touchscreen works
A capacitive touchscreen is a glass panel covered with a transparent resistive material (usually an indium oxide / tin oxide alloy). The electrodes located at the corners of the screen apply a small alternating voltage to the conductive layer (the same for all corners). When you touch the screen with a finger or other conductive object, current leakage occurs. In this case, the closer the finger is to the electrode, the lower the resistance of the screen, which means that the current is greater. The current in all four corners is recorded by the sensors and transmitted to the controller, which calculates the coordinates of the touch point.
In earlier models of capacitive screens, direct current was used - this simplified the design, but with poor user contact with the ground, it led to failures.
Capacitive touch screens are reliable, about 200 million clicks (about 6 and a half years of clicks with an interval of one second), do not let liquids through and perfectly tolerate non-conductive pollution. Transparency at 90%. However, the conductive coating is still vulnerable. Therefore, capacitive screens are widely used in machines installed in a protected room. Does not respond to gloved hands.
How Projected Capacitive Touch Screens Work
A grid of electrodes is applied to the inside of the screen. The electrode together with the human body forms a capacitor; electronics measure the capacity of this capacitor (gives a current pulse and measures voltage).
Principle of operation of the projected capacitive touch screen
The transparency of such screens is up to 90%, the temperature range is extremely wide. Very durable (bottleneck - complex electronics that handle pressing). Glass with a thickness of up to 18 mm can be used on PEE, which leads to extreme vandal resistance. They do not react to non-conductive pollution, conductive ones are easily suppressed by software methods. Therefore, projected capacitive touch screens are used in vending machines installed outdoors. Many models react to a gloved hand. In modern models, designers have achieved very high accuracy - however, vandal-resistant designs are less accurate.
PEE even react to the approach of a hand - the trigger threshold is set by software. Pressing by hand is distinguished from pressing with a conductive stylus. Some models support multi-touch. Therefore, this technology is used in touchpads and multi-touch screens.
It is worth noting that due to differences in terminology, surface and projected capacitive screens are often confused. According to the classification used in this article, the iPhone screen is projected-capacitive.
Conclusion
Each type of touch screen has its own advantages and disadvantages, for clarity, consider the table.
| Resistive 4-wire | Resistive 5-wire | Capacitive | Projected capacitive | |
|---|---|---|---|---|
| Functionality | ||||
| Gloved hand | Yes | Yes | No | Yes |
| Solid conductive object | Yes | Yes | Yes | Yes |
| Solid non-conductive object | Yes | Yes | No | No |
| Multitouch | No | Yes | Yes | Yes |
| Measuring pressing force | No | No | No | Yes |
| Limiting transparency,% | 75 | 85 | 90 | 90 |
| Accuracy | Height | Height | Height | Height |
| Reliability | ||||
| Lifetime, million clicks | 10 | 35 | 200 | ∞ |
| Protection against dirt and liquids | Yes | Yes | Yes | Yes |
| Resistant to vandalism | No | No | No | Yes |
The article was written based on the materials of the site
In our time, touch screens have long ceased to be exotic. Outwardly they are all similar, but are these displays really the same? Let's look at the design of the main types of sensitive screens, their advantages, disadvantages and scope.
Today, the most widespread sensors are based on capacitive and resistive technologies, as well as on their varieties.
"Multitouch"
This is the name of the technology that allows you to recognize pressing on the touch screen at several points at the same time. This opens up new possibilities in device management. An example of using multitouch technology is the Apple iPhone interface.
Capacitive touch screens
 | For example: Tne Prada Phoneby LG |
The capacitive touchscreen display actually responds to touch. It is a glass panel coated with a transparent conductive compound. In the corners of the panel there are four electrodes to which an alternating current is supplied. The moment the user touches such a screen with a finger, an electric charge from the conductive layer flows over the skin to the human body. The screen controller measures the current generated across all four electrodes - it is proportional to the distance from the corner of the panel to the touch point. Comparing the obtained values, you can find out the exact coordinates of the point of contact. Sensors operating on this principle can be distinguished "by touch" - they are triggered by a light touch, and respond faster and more clearly to pressing with a fingertip than with a nail. Moreover, they do not react to pressing any other objects, especially if they are non-conductive. Therefore, a phone with such a screen cannot be operated with a gloved hand. In addition, as the temperature decreases, the electrical characteristics of the sensor change, and the screen begins to work worse. We add that this principle is usually used in notebook touchpads.
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 | For example: Apple iPhone |
Projected capacitive screens
There is another type of capacitive sensor - a projected capacitive screen. On the back there is a grid of electrodes. At the point where the hand touches, the electrical capacitance changes (according to the laws of electrodynamics, the human body is a capacitor), the controller determines at which intersection of the electrodes this happened, and calculates the coordinates. Such screens, in addition to high transparency and durability, have two more important advantages - the glass-substrate can be made arbitrarily strong (and rather thick), moreover, they support "multitouch". The downside is lower accuracy compared to conventional capacitive technology.
Resistive touch screens
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 | For example: HTC Touch Diamond |
The resistive sensor is de facto pressure sensitive. The screen consists of two plates, between which there is a non-conductive compound. If you touch the outer flexible (and transparent) plate with your finger (or any other object - in this case it does not matter), the plates are closed and current begins to flow at the point of contact. To determine the location of the touch, the screen controller measures the voltage between the electrodes located at the edges of the panel in pairs. Such a screen is called 4-wire (there are also 5-wires with some differences).
The peculiarity of the resistive screen is that it requires physical effort to trigger it, and it recognizes pressing with a fingernail better than a pad, reacts to any objects touching the surface. Devices with resistive screens are often equipped with styluses. Such a display provides a higher control accuracy (it is possible to literally hit a pixel with a stylus, while a finger on a capacitive screen - only in a large enough area), but due to constant contact with hard objects, the flexible plate is quickly covered with scratches. Most mobile devices are equipped with resistive screens.
Other types of touch screens
There are also a number of sensor technologies, often quite exotic. For example, using a grid of infrared rays or even generating ultrasonic vibrations. The latter is known as surface acoustic wave technology. There are systems based both on cameras that track motion ("multitouch" is also supported here), and on the basis of strain-gauge coatings, the deformation of which changes the electrical resistance.
Everyone has probably heard of the development of tactile displays by companies, and this is no longer a myth. The only obstacle on the way to a wide audience is the emergence of a universal screen with the highest sensitivity, that is, today specialists are faced with the task of making a tactile display, in all respects, practical. Such an alternative to vibration motors will help to recreate contact with the device, as with a push-button device, and even more ...
Touchscreen displays of the near future
Thanks to some companies, the progress of technology is evident, and now there are not one, but several prototypes. One of these was Microsoft, its research group "" under the leadership of Hong Tan, was able to move in the tactile direction.
A group of specialists have spent several years creating a feedback screen, and their work is already presented in several variations, including those based on Nokia Lumia. You can verify the state of affairs from the video clip below:
According to lead researcher Hong Tan, touchscreens need to evolve into something more. “What can be considered a really cool achievement is taking a smooth piece of glass and making it something special,” says Ms. Tang. "It's almost magic."
Researchers at Microsoft work in two directions, developing the hardware and software components of the technology. The main task is full feedback, not only on pressing the number buttons, but also on the image as a whole. This is how some of the screen options give you a real feel for textures under your fingers. One example is the chessboard from the Nokia Lumia app. Different colored cells have different tactile effects.
Instead of an afterword
Basically, the technology of future screens is based on stimulating receptors on the skin, as well as muscle motility. On the screens you can feel not only the punching of the surface under the finger, but also a characteristic click, indicating contact.
“When you type on your smartphone's virtual keyboard, the outer layer literally instantly flexes under your fingers. This is a very slight deflection, but it is also enough for your fingers to receive a signal that reminds you that you have pressed a button, ”says Ms. Hong.
the iPhone 2G was the first mobile phone to be completely touch-based. More than ten years have passed since its presentation, but many of us still do not know how the Touchscreen works. And we come across this intuitive input not only in smartphones, but also in ATMs, POS terminals, computers, cars and airplanes - literally everywhere.
Before touchscreens, the most common interface for entering commands into electronic devices was various keyboards. Although it seems that they have nothing in common with touchscreens, in fact, how much the touchscreen is similar in principle to a keyboard can be surprising. Let's take a look at their structure in detail.
The keyboard is a printed circuit board on which several rows of switch-buttons are installed. Regardless of their design, membrane or mechanical, when each key is pressed, the same thing happens. An electrical circuit is closed on the computer board under the button, the computer registers the passage of current in this place of the circuit, "understands" which key is pressed and executes the corresponding command. In the case of a touchscreen, much the same happens.
There are about a dozen different types of touch screens, but most of these models are either outdated and not used for a long time, or are experimental and are unlikely to ever appear in serial devices. First of all, I will talk about the device of current technologies, those of them that you constantly interact with, or at least you may encounter in everyday life.
Resistive touch screen
Resistive touchscreens were invented back in 1970 and have changed little since then.
In displays with such sensors, a couple of additional layers are located above the matrix. However, I will make a reservation, the matrix is \u200b\u200bnot at all necessary here. The first resistive touchscreen devices were not screens at all.
The bottom sensory layer consists of a glass base and is called the resistive layer. It is coated with a transparent metal coating that transfers current well, for example, from a semiconductor such as indium tin oxide. The top layer of the touchscreen, with which the user interacts by pressing the screen, is made of a flexible and resilient membrane. It is called a conductive layer. An air gap is left in the space between the layers, or it is evenly dotted with microscopic insulating particles. At the edges, four, five or eight electrodes are brought to the sensor layer, connecting it with sensors and a microcontroller. The more electrodes, the higher the sensitivity of the resistive touchscreen, since the change in voltage across them is constantly monitored.
Here is the resistive touchscreen on. Nothing happens yet. Electric current flows freely through the conductive layer, but when the user touches the screen, the membrane bends from above, the insulating particles part, and it touches the lower layer of the touchscreen, comes into contact. This is followed by a change in voltage at once on all the electrodes of the screen.
The touchscreen controller detects voltage changes and reads the readings from the electrodes. Four, five, eight meanings and all are different. Based on the difference in readings between the right and left electrodes, the microcontroller will calculate the X-coordinate of pressing, and based on the differences in the voltage on the upper and lower electrodes, it will determine the Y-coordinate and, thus, tell the computer the point at which the layers of the touch layer of the screen touched.
Resistive touchscreens have a long list of disadvantages. So, in principle, they are not able to recognize two simultaneous clicks, let alone a larger number. They behave badly in the cold. Due to the need for an interlayer between the layers of the sensor, the matrices of such screens noticeably lose in brightness and contrast, tend to glare in the sun, and generally look noticeably worse. However, where image quality plays a secondary role, they continue to be used due to their resistance to dirt, glove-like use and, most importantly, low cost.
Such input devices are ubiquitous in low-cost mainstream devices such as public information terminals and are still found in obsolete gadgets such as cheap MP3 players.
Infrared touch screen
The next, much less common, but, nevertheless, actual variant of the touch screen is the infrared touchscreen. It has nothing to do with a resistive sensor, although it performs similar functions.
The infrared touchscreen is constructed from arrays of LEDs and light-sensitive photocells located on opposite sides of the screen. LEDs illuminate the surface of the screen with invisible infrared light, forming a kind of cobweb or grid on it. This is reminiscent of the burglar alarms shown in spy action movies or computer games.
When something touches the screen, no matter if it's a finger, a gloved hand, stylus, or pencil, two or more beams are interrupted. Photocells record this event, the touchscreen controller finds out which of them receive less infrared light and, based on their position, calculates the area of \u200b\u200bthe screen in which the obstacle has arisen. The rest is to match the touch to which interface element is on the screen at that location - it's up to the software.
Today, infrared touch screens can be encountered in those gadgets whose screens have a non-standard design, where it is technically difficult or impractical to add additional touch layers - in e-books based on E-link displays, for example, the Amazon Kindle Touch and Sony Ebook. In addition, the military liked devices with similar sensors because of their simplicity and maintainability.
Capacitive touch screen
If in resistive touch screens the computer registers the change in conductivity following pressing on the screen directly between the layers of the sensor, then capacitive sensors record the touch directly.
The human body and skin are good conductors of electricity and have an electrical charge. Usually, you notice this by walking on a woolen carpet or taking off your favorite sweater and then touching something metallic. We are all familiar with static electricity, have experienced its effects on ourselves and have seen tiny sparks escaping from our fingers in the dark. A weaker, imperceptible exchange of electrons between the human body and various conducting surfaces occurs constantly and it is this that is fixed by the capacitive screens.
The first such touchscreens were called surface-capacitive and were a logical development of resistive sensors. They have just one conductive layer, similar to the one used before, installed directly on top of the screen. Sensitive electrodes were also attached to it, this time at the corners of the touchpad. The sensors monitoring the voltage on the electrodes and their software were made noticeably more sensitive and now could pick up the slightest changes in the flow of electric current across the screen. When a finger (another conductive object, such as a stylus) touches a surface with a surface-capacitive touchscreen, the conductive layer immediately begins to exchange electrons with it, and the microcontroller notices this.
The appearance of surface-capacitive touchscreens was a breakthrough, but due to the fact that the conductive layer applied directly over the glass was easily damaged, they were not suitable for new generation devices.
Projection capacitive sensors were required to create the first iPhone. This type of touchscreen has quickly become the most common in today's consumer electronics: smartphones, tablets, laptops, candy bars and other home appliances.
The top layer of this type of touchscreen has a protective function and can be made of tempered glass such as the famous Gorilla Glass. Below are the thinnest electrodes that form a grid. At first, they were superimposed on each other in two layers, then, to reduce the thickness of the screen, they began to be placed on the same level.
Made of semiconductor materials, including the already mentioned indium tin oxide, these conductive hairs create an electrostatic field at their intersections.
When a finger touches the glass, due to the electrical conductive properties of the skin, it distorts the local electric field at the points of the nearest intersections of the electrodes. This distortion can be measured as the change in capacitance at a single grid point.
Since the array of electrodes is made quite small and dense, such a system is able to track the touch very accurately and easily picks up multiple touches at once. In addition, the absence of additional layers and interlayers in a sandwich made of a matrix, sensor and protective glass has a positive effect on the image quality. However, for the same reason, broken screens are usually replaced completely. Once assembled together, a Projected Capacitive Sensor screen is extremely difficult to repair.
Now the advantages of projected capacitive touchscreens do not sound like something surprising, but at the time of the iPhone presentation, they provided technology with tremendous success, despite the objective disadvantages - sensitivity to dirt and moisture.
Pressure Sensitive Touch Screens - 3D Touch
The forerunner to pressure-sensitive touchscreens is Apple's proprietary Force Touch technology used in the company's smartwatches, MacBook, MackBook Pro, and Magic Trackpad 2.
After testing interface solutions and various scenarios for using pressure recognition on these devices, Apple began to implement a similar solution in its smartphones. In the iPhone 6s and 6s Plus, pressure recognition and measurement has become one of the functions of the touchscreen and has received the commercial name 3D Touch.
Although Apple did not hide the fact that the new technology only modifies the capacitive sensors we are used to and even showed a diagram that explained in general terms the principle of its operation, the details about the device of touch screens with 3D Touch appeared only after the first iPhones of the new generation were dismantled by enthusiasts ...
In order to teach the capacitive touchscreen to recognize pressures and distinguish between multiple degrees of pressure, the Cupertino engineers required a reassembly of the touchscreen sandwich. They made changes to individual parts of it and added another, new layer to the capacitive layer. And, interestingly, in doing so, they were clearly inspired by outdated resistive screens.
The grid of capacitive sensors remained unchanged, but it was moved back, closer to the matrix. An additional array of 96 individual sensors was integrated between a set of electrical contacts that monitor the touch point of the display and the protective glass.
His job was not to locate his finger on the iPhone screen. The capacitive touchscreen still coped well with this. These plates are required to detect and measure the degree of bending of the protective glass. Apple specifically for the iPhone ordered Gorilla Glass to design and manufacture a protective coating that would retain its previous strength and, at the same time, be flexible enough to allow the screen to respond to pressure.
On this development, it was possible to finish the material about touch screens, if not for another technology, which was predicted a great future several years ago.
Wave touch screens
Surprisingly, they do not use electricity or even have anything to do with light. Surface Acoustic Wave system technology uses surface acoustic waves that propagate along the surface of the screen to determine the point of contact. The ultrasound generated by the piezoelectric elements in the corners is too high for human hearing to pick up. It spreads back and forth, repeatedly bouncing off the edges of the screen. The sound is analyzed for anomalies created by objects touching the screen.
There are not many disadvantages to wave touch screens. They start making mistakes after heavily soiled glass and in conditions of strong noise, but, at the same time, screens with such a sensor do not have additional layers that increase the thickness and affect the image quality. All sensor components are hidden under the display bezel. In addition, wave sensors allow you to accurately calculate the area of \u200b\u200bcontact of the screen with a finger or other object and indirectly calculate the pressure on the screen using this area.
We are unlikely to encounter this technology in smartphones because of the current fashion for frameless displays, but a few years ago Samsung experimented with the Surface Acoustic Wave system in monoblocs, and panels with acoustic touchscreens are sold as accessories for gaming machines and advertising terminals. now
Instead of a conclusion
In a very short time, touchscreens have conquered the world of electronics. Despite the lack of tactile feedback and other shortcomings, touch screens have become a very intuitive, understandable and convenient method of entering information into computers. Last but not least, they owe their success to the variety of technical implementations. Each with its own advantages and disadvantages, suitable for its class of devices. Resistive screens for the cheapest and most mainstream gadgets, capacitive screens for smartphones and tablets and desktops with which we interact every day and infrared touchscreens for those cases where the screen design should be left intact. In conclusion, it remains only to state that touch screens are with us for a long time, they are not expected to be replaced in the near future.Before considering a capacitive or resistive screen, you need to decide what kind of touch technology is in general. Everything is clear here: this is the screen that determines the coordinates of the press. Scientifically speaking, this refers to the method of managing the interface, with which the user can click directly on the place of interest. At the moment, there are several methods for implementing touch screens. It is worth considering each separately.
Resistive technology
To determine which type of screen, capacitive or resistive, is best for you, you need to consider them. The second option involves the use of a specific production technology. Below is a glass panel, on top of which there is a transparent flexible membrane. There is a conductive coating on the panel and membrane, that is, resistive. When you tap the screen, it closes at a certain point. If you know the voltage across the electrodes on one side and measure it on the membrane, you can track one coordinate. Two coordinates will require you to turn off one group of electrodes to turn on the other. All this is done automatically by the microprocessor as soon as the voltage across the membrane changes. Resistive screens do not allow multi-touch.
Features of resistive technology
Like any other type of implemented device, there are certain traits that are positive or negative, depending on the situation. As advantages, cheap production is usually noted, as well as the ability to press with anything, since you only need to push the membrane. Positioning accuracy is increased by using stylus.
Negative moments
The main disadvantages are a low degree of light transmission, a high rate of scratches on the surface, the ability to press one point no more than 35 million times, the inability to implement multitouch. If you cannot decide whether to choose a capacitive or a resistive screen, then it is important to note the impossibility of using gestures such as sliding, since you need to press your finger on the screen and keep holding it. In devices with such controls, it is better to use software that requires minimal use of “flipping” gestures.
Understanding the features of this technology, it is worth noting that it can be implemented in several ways that have certain differences. A capacitive touchscreen can be simply capacitive and projected capacitive. The first option involves the use of certain elements. A transparent resistive material, such as an alloy of tin oxide or indium oxide, is placed over the glass panel. In the corners there are electrodes that apply a small alternating voltage to the conductive layer. If the screen is touched with a conductive object, then a leak occurs, and the closer this object is to the electrode, the lower the resistance of the screen, that is, the current increases markedly. And all this is called a capacitive screen, since the alternating current is conducted by an object of greater capacity. Most often we are talking about a finger.
Features of capacitive screens
Like other types of technology, in this case we are talking about a combination of advantages and disadvantages. The advantages over the others include high light transmittance, significant resource of clicks, simplicity and ease of use by the “paging” method. There are also disadvantages here: you only need to use your fingers or specialized styluses. Conventional capacitive screen does not support multitouch technology. There are often accidental clicks. For example, the system can recognize the gesture as “flipping” even when it is not supposed to be, since it is difficult to keep the finger strictly in one place after pressing.
Projected capacitive touchscreen
In this case, the device differs from the previous ones quite strongly. The inner side of the screen is a grid of electrodes. If an object of greater capacity touches the electrode, a capacitor is formed with a constant capacity. Such screens are used outdoors, as they allow you to install glass, the thickness of which reaches 18 mm, while it is possible to obtain not only the most hard surface, but also to ensure vandal resistance.
Features of projected capacitive sensors
In this case, as in all others, there are certain advantages and disadvantages that you should be aware of. The advantages include the ability to implement multitouch, response to pressing with a glove, a high degree of light transmission, as well as the durability of the screen itself. Such screens are capable of responding to the approach of fingers without the fact of pressing. The threshold at which touch completion occurs is usually programmatically configurable. The extreme point is usually the screen itself, since it is completely useless to push through it.
If we consider a projection-capacitive screen, then it also has certain drawbacks, which are usually called complex and rather expensive electronics, the inability to use a conventional stylus, and the likelihood of accidental clicks.
Multi-touch technology
It is impossible to determine the appropriate type of touch screen, capacitive or resistive, without deciding the question regarding the implementation of this technology. Multi-touch is a multi-touch capability. This implementation assumes tracking the coordinates of several clicks at the same time. If such technology is implemented in a smartphone or tablet, then it can be used to imitate playing a musical instrument, for example, a guitar. You should deal with this in more detail.
You can take a conventional capacitive or resistive screen. If you press first, for example, in the upper left corner, and then, without lifting your finger, press the other in the lower right, then the electronics will determine the center of the screen as coordinates, that is, the middle of the segment between a pair of these touches. This will be visible if you launch a special application that tracks the coordinates of the press. However, the question arises: how is the scaling of pictures implemented if only one click is recognized anyway?
Everything is simple here. This is the most common software trick. You pressed the capacitive screen - the electronics detected it. This will be point "A". Now, without releasing your finger, you press to another place, which will be point "B", it turns out that at this moment the point of pressing moved instantly to the side, forming "C". It was at this moment, when there was no actual release of the finger, and the pressure point instantly moved, it is programmatically processed as a multitouch. Further, if point "C" gets closer to "A", then the shift of fingers is determined, that is, in the case of an image, the picture must be reduced, and vice versa. Another point: if point "C" describes an arc around one of the points, then the program defines it as rotation of one finger around the other, which necessitates the rotation of the picture in the appropriate direction.
Using resistive and capacitive screens
The first type is traditionally used by professional developers, since it allows you to control any object under various weather conditions. When implementing resistive technology, more sensors are used per square centimeter than capacitive ones, so the display can display the smallest icons that can be pressed with a needle. For example, the Windows Mobile operating system was designed with this feature in mind, so it works well with resistive screens. Such displays are almost insensitive to accidental presses. However, many developers are now aiming to create applications targeting capacitive touchscreens. This is already becoming a problem for devices made with resistive technology.
Security degree
It is important to understand that for tablet computers and communicators, the display is the most vulnerable part. A capacitive screen is the preferred option for reliability. Its performance in any conditions is noticeably higher, and resistive models can fail, for example, if they are carried down with glass. A capacitive screen is a fail-safe option. Even if it is broken, it will continue to perform its functions. If you decide whether to choose a capacitive or resistive screen, then it is worth noting that in the field, the first will be the best option.
conclusions
Summing up, it can be noted that both display options have their own advantages and disadvantages. While the capacitive screen is a whole set of possibilities, the resistive screen is focused on use in certain situations. Usually it all depends on the interface used in the gadget. it is convenient to use, its pressing area is noticeably smaller than that of a finger, however, with good surface responsiveness, it is convenient to do without this device. The constant improvement of resistive displays has led to the fact that models have appeared quite solid, that is, resistant to scratching, but at the same time responsive. Such options have become very easy to use.
The need to use a special stylus for capacitive screens is sometimes quite inconvenient, since it usually does not come with the device. And the resistive technology presupposes both the accompaniment of a special device and the possibility of pressing with any solid object. One of the reasons why many people choose a capacitive touchscreen is multitouch, but it is worth noting that most often this is a software implementation, as already described, and with the proper approach, it can be applied to a resistive one. Projected Capacitive Technology has not yet become as affordable as we would like it to be.
