There is a touch screen that can be done. DIY touch monitor

At first, touchscreens (touch screens) were quite rare. They could be found only in some PDAs, PDAs (Pocket Computers). As you know, devices of this kind have not gained wide distribution, since they lacked the most important thing, that is, functionality. The history of smartphones is directly related to touchscreens. That is why at the present time you will not surprise a person with a “smart phone” with a touch screen. The touchscreen is widely used not only in fashionable expensive devices, but even in relatively inexpensive models of modern phones. What are the principles of operation of the 3 types of touch screens that can be found in modern devices.

Touchscreen types

Touch screens are no longer too expensive. In addition, touchscreens (touchscreen) today are much more "responsive" - ​​the user's touch is recognized just fine. It is this characteristic that paved the way for them to a large number of users around the world. At the present time, there are three main designs of touchscreens:

1. Capacitive.
2. Wave.
3. Resistive or simply "elastic".

Capacitive touchscreen: how it works

In touchscreen designs of this kind, the glass base is covered with a layer that acts as a charge storage container. The user releases part of the electric charge at a certain point with his touch. This reduction is determined by chips that are located in each corner of the screen. The computer calculates the difference in electrical potentials that exist between different parts of the screen, while information about the touch in detail is immediately transmitted to the touchscreen driver program.

A rather important advantage of capacitive touchscreens is the ability of this type of screen to maintain almost 90% of the original brightness of the display. Because of this, images on a capacitive screen look sharper than on touchscreens that have a resistive design.

Capacitive touch screen video:

The Future: Wave Touch Displays

At the ends of the grid axes of the glass screen there are two transducers. One of them is the transmitter, the second is the receiver. On a glass base, there are also reflectors that “reflect” an electrical signal that is transmitted from one to another transducer.

The receiver-transducer absolutely “knows” whether there was a press, and also at what specific point it happened, since the user interrupts the acoustic wave with his touch. At the same time, the glass of the wave display does not have a metal coating - this makes it possible to preserve 100% of the original light in full. In this regard, the wave screen is the best option for those users who work in graphics with fine details, because resistive and capacitive touch screens are not ideal in terms of image clarity. Their coating delays light, which as a result significantly distorts the picture.

Video about the principle of operation of touch screens on SAW:

Past: about the resistive touchscreen

A resistive system is an ordinary glass, which is covered with a layer of an electricity conductor, as well as an elastic metal "film", which also has conductive qualities. There is an empty space between these 2 layers with the help of special spacers. The screen surface is covered with a special material that protects it from mechanical damage, such as scratches.

An electric charge in the process of a user working with a touchscreen passes through these two layers. How does this happen? The user at a certain point touches the screen and the elastic upper layer is in contact with the conductive layer - only at this point. Then the computer determines the coordinates of the point that the user has touched.

When the coordinates become known to the device, a special driver translates touches into commands known to the operating system. In this case, you can draw analogues with the driver of the most ordinary computer mouse, because it does exactly the same thing: it explains to the operating system what the user specifically wanted to tell her by moving the manipulator or pressing a button. With screens of this type, as a rule, special styluses are used.

Resistive screens can be found in relatively old devices. Just such a touch screen is equipped with IBM Simon - the most ancient smartphone of those that were conscious of our civilization.

Video about the principle of operation of a resistive touch screen:

Features of different types of touchscreens

The cheapest touch screens, but at the same time, the least clearly broadcasting the image are resistive touch screens. In addition, they are also the most vulnerable, because absolutely any sharp object can seriously damage a fairly delicate resistive “film”.

The next type, i.e. wave touchscreens are the most expensive among their kind. At the same time, the resistive design, most likely, refers, nevertheless, to the past, capacitive - to the present, and wave - to the future. It is clear that the future is absolutely unknown to anyone and, accordingly, at the present time, one can only assume which technology has great prospects for its use in the future.

For a resistive touchscreen system, it does not really matter whether the user touches the screen with the rubber tip of the stylus or simply with their finger. It is enough that there is contact between the two layers. At the same time, the capacitive screen recognizes only touches with some conductive objects. Often, users of modern devices work with them using their own fingers. In this respect, the screens of the wave design are closer to the resistive ones. You can give a command with almost any object - you just need to avoid using heavy or too small objects, for example, a ballpoint pen refill is not suitable for this.

Do-it-yourself touch screen - sounds a bit strange. But why is that? Now more and more computer devices with a touch screen are being produced. And the future, of course, belongs to this technology.

But is it affordable for everyone? Plus or minus, who has what opportunities.

Optical touch screen- Here's what you can do at home. And for this we need 6 things:

- Thick white sheet of paper (1 piece);
- Scissors (also 1 piece);
— Webcam of any cost;
— Photo frame with glass;
- Pencil;
- Cardboard box.

Instructions for creating a touch screen

A sheet is inserted into the photo frame. A hole is made at the bottom of the box for the webcam. In principle, here you can do without a pencil, but scissors, than to pierce the box, are a must. Now we need to place the glass frame in the box so that the webcam "looks" at the glass, and we look at the paper.

But here we can not do without software. Community Core Vision and virtual mouse driver are a must. Luckily, the license allows the whole thing to be downloaded and installed for free.

This interesting video review will help with everything with details and explanations:

It's interesting to look at all these things. But doing it yourself is already much more difficult and doubly interesting. Therefore, those who will make this miracle, I want you to share your impressions. How is it and what.

With each new day, humanity makes more and more discoveries, develops, trying to reach new heights in any area of ​​its life. One of these breakthrough phenomena can definitely be called a modern cell phone, which, in addition to many functions, also has a touch screen. Almost everyone has a smartphone, respectively, and life without it is quite difficult to imagine. Therefore, it is important to know how to care for it so that it lasts longer, but other than that, you need to understand what needs to be done to keep its touch screen in order. And this is important insofar as the display is the basic part of any phone. Since it provides a touch screen, in case of any problems, we can not only not see the contents of the software of our phone, but it is also unlikely that we will be able to control it. This is what will be discussed in today's article.

Modern phone: what is it?

In very rare cases, you can catch a person without their smartphone or its accessories in everyday life. The answer to the question of why this is so is quite simple. Because modern phones literally can do everything and even more. Radio receivers, portable speakers and MP3 players, bulky cameras and cameras, massive and uncomfortable phones, ordinary stationary computers and many other equipment that the modern smartphone replaces, look like a gloomy past century against its background. This touch screen marvel may soon replace our real life! So what to do if something is wrong with this very screen? Let's think together.

Touch screens "touchscreen" - what is it?

At its core, this is an input device adapted to our convenience. It can be said that the whole market is behind the touch screen phone, because it is convenient, beautiful and fashionable. Now consider the principle of its work.

The touch screen display gives us the ability to interact with any device without special buttons, but only through sensors.

Entering any information using such a screen is carried out due to the special structure of the display, which is sensitive to touch. Where are they used?

Application

This technology is rightfully considered a real breakthrough, because it greatly simplifies various kinds of manipulations with electrical engineering. At the moment, they are simply the widest application: from phones, as mentioned earlier, to modern TVs and terminals for making payments. In addition to all this, the touch screen for Samsung and iPhone, which, by the way, occupy a leading position in the modern technology market, has long been an inherent part.

Screen classification

Since today screens with sensors are very popular and, therefore, in demand, then, according to the principle "demand creates supply", they are trying to be introduced into almost every area related to technology. As a result, the methods and principles of their production, as well as models, can be classified into several different types. There are about four main types in total. If we consider various subtypes, then this figure increases many times. Let's look at the types of such screens: resistive; screens based on surface acoustic waves; infrared and capacitive.

Resistive screens

Just this type of screens finds its application in mobile devices, which will be discussed later. The structure of resistive screens is quite simple. It includes: the LCD display itself, as well as two transparent plates that will be installed above this display. Between such plates there is a dielectric layer. There are only two advantages of this type of screens: a rather low cost of components and, accordingly, creation (in other words, cost) and good sensitivity.

Screens based on surface acoustic waves

The principle of operation of such screens is more complex. It is based on the phenomenon of absorption of ultrasonic waves. The advantages of this type are that:

• They are durable.
• Very transparent.
• They can determine not only the coordinates of the pressing point, but also the degree of this very pressing. By the way, resistive screens were not able to do this.

But surface-acoustic screens also have disadvantages: the presence of even small vibrations and noises (meaning acoustic), as well as dirt, can contribute to disruptions in the operation of the screen or its complete failure.

They are used, for example, in slot machines that have a large touch screen.

Infrared screens

This type of screen is based on a principle similar to the structure of surface-acoustic screens. The only difference is that infrared radiation is taken as the basis. The screen itself is represented by many infrared and mutually perpendicular lines. When the user touches the screen, the integrity of the radiation is broken at the touch point, and the device reads information about the coordinate location of this point. Advantages: the possibility of convenient reconstruction, strength and durability. Application: vending machines.

When you press the surface of such a screen, a current pulse is generated at the touch point, due to which the device reads information about the touch and its coordinates. The advantages of capacitive screens include a very fast response time and high performance. Disadvantage: close dependence on external temperature, due to which it may involuntarily stop its work. Application: ATM terminals, Apple touch products.

The touch screen does not work. What to do?

The biggest problem in this situation is the fact that for most modern mobile devices, the touchscreen display is the only means of interacting with the device. Of course, in the event of a sensor failure, the entire performance of such a device goes to zero. The question naturally arises, why does the touch screen stop working?

There can be many answers to such a question: both a banal breakdown, and contamination of the sensor or microcircuits, and the ingress of water or some other substance into the layer between the display and the film. But with all the variety of problems, do not despair: there is always a way out. We will show you some simple first aid methods for your smartphone.

Basic and simple troubleshooting steps

The first thing you can try to do with a faulty smartphone yourself is to follow these steps:

Important: Always use a dry or slightly damp screen cloth, but never wet!

This is perhaps the most basic screen troubleshooting tip. If the damage in the software is not serious or the contamination is superficial, then this will be enough. If this did not help you, do not rush to carry your smartphone to a service center and pay a lot of money for repairs. Please read the article to the end.

Troubleshooting steps for an insensitive screen

If you are sure that your screen has stopped responding to touch and movement, not due to any impact (for example, falling) or getting water into it, then the following steps should help for sure:

1. Thoroughly clean and dry your hands.
2. After turning off the smartphone and removing the protective devices, make sure that the screen and protective film remain intact and clean. Otherwise, you will need to wipe off any dirt and liquids from the screen surface and screen protector with a dry, lint-free cloth.
3. Remove all peripheral devices (SIM cards, USB cable, various adapters, and so on).
4. If the screen is completely insensitive, you will have to go to the step of forced rebooting the device. For an Android device, it will look like this: simultaneously hold down the "Power" keys (usually located on the sidebar on the right) and "Volume down" for 7-10 seconds. For users of Apple products, you will have to use a slightly different instruction, depending on the versions of your device. For iPhone 6 users: hold down the "Power" and "Home" keys until the "apple" appears on the screen. For users of iPhone version 7 and higher, the following instruction may come up: hold down the "Power" and "Volume down" keys also until the logo appears.
5. After a successful reboot of the device, you should check the performance of its sensors.

What to do if the phone has been dropped on a hard and/or wet surface? In this case, the screen of your device stops responding due to an internal malfunction. However, even in this case, you can try to bring it to its senses and make it work again without the help of service centers. Of course, this is possible if the damage is not very serious and you are confident in what you are doing. If you are afraid of doing something wrong, then it is better to leave this matter to professionals without resorting to any of the above steps. So let's get started.

When the touch screen stops functioning after the phone is dropped, it may be due to a problem in the connection of the device that digitizes external signals. In this case, you can tap gently on each corner of the phone, which may cause the connection to reconnect.

If the phone fell not on a hard surface, but in a liquid (usually water), then in order to return it to functioning, the following steps must be urgently performed:

1. Turn off your phone and remove the battery.
2. Wipe off the water with a dry rag.
3. Try to remove water from the phone connectors (microphone, speaker, headphone jack and charging).
4. Put down the phone, surrounding it with a drying agent.
5. Leave the smartphone for a long time (at least 48 hours).

It is worth noting that often people use rice as a drying agent, although it is not. For this, silica gel is perfect.

You should understand that you can solve the problem of a non-working screen at home only in cases where the problem is not so serious that the need for specialist help is visible to the naked eye. If none of our methods solved the problem, it means that the damage to the screen or software is very serious. As a rule, such serious problems are quite difficult to understand and fix on your own, and you cannot do without the help of a professional, because you may need to change the touch screen. In this case, there can be only one advice: contact the service center.

Touch input panels are ubiquitous today. They are installed on smartphone and tablet displays, laptop touchpads, graphic tablets, payment terminals and ATMs, as well as medical and industrial equipment. Manufacturers make touchscreen all-in-ones and TVs, but most PC displays are still touch insensitive.

About, how to make a regular monitor - touch, probably thought many. Indeed, in some operations (reading, working with graphics, editing texts), scrolling through a page, selecting the desired item or selecting an area on the screen with a pen or finger is much easier, faster and more convenient than moving the cursor or turning the mouse wheel. At first glance, it seems that this idea is a fantasy, and it is difficult to realize it. But in fact, everything is a little simpler. Asmake the monitor touchindependently - this material will tell.

A bit of theory

The touch surfaces of the screens are structurally a separate element that is not directly connected with the display matrix. Of course, in the latest generations of smartphones and tablets, so-called OGS panels are used, in which the sensing element is embedded between the pixels, but it is still controlled via a separate bus. In total, there are three types of touchscreens, each with its own characteristics.

resistive

Resistive touch screen technology is the simplest and cheapest. According to the principle of operation, such touchscreens are related to computer keyboards. On two layers of a transparent substrate, tracks made of an almost transparent conductive material are applied. These two layers are located on top of each other with a gap of a few micrometers. The upper one is necessarily flexible and bends when touched by a finger, closing the tracks. The farther the fault is, the longer the current travels and the higher the resistance. By its value (with an accuracy of ohms), the sensor controller calculates where the click occurred.

Resistive touch screens are cheap, simple, react to any object, but are not reliable enough (a small cut can disable the touchscreen) and have limited transparency (at a certain angle, conductor tracks even become visible).

capacitive

The capacitive touchscreen is the most common in our time (as of 2016). It is more perfect and reliable. The number of layers was reduced to one, its thickness became less. A grid of transparent, low-resistance conductors is applied to the surface of the touch glass or film. The human body is a poor conductor of electricity and is capable of accumulating an electric charge, therefore, when a finger touches the glass, a small current leakage occurs, the location of which is determined by the controller.

Wave

The wave touch screen uses acoustic (ultrasound, SAW technology) or light (infrared, ultraviolet, PSV technology) waves to register touches. A frame is installed around the perimeter of the screen, which combines the emitter and the recorder. When a finger touches the surface, it absorbs and partially reflects the wave, and the sensors register the place.

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SAW and PSV screens are reliable, absolutely transparent (there is no grid of electrodes), they have an inexhaustible theoretical resource (in reality it depends on the quality of the components), if there is a protective frame, the sensor itself cannot be damaged, and the use of bulletproof glass makes the screen matrix invulnerable. Therefore, they are often used in ATMs, payment terminals, industrial machines and medical equipment. But the accuracy of determining the coordinates of the finger they have mediocre. Also, wave touchscreens require regular wiping (dirt on the glass causes phantom reactions).

There are other types of display sensors, but they are much less common. In addition, these methods are difficult to implement at home, so they are not considered.

Application of sensors in practice

When applied to touch monitors, all three technologies are in demand. The resistive type was widely used earlier, but is still found today. It is he who is interesting in terms of, but more on that below. Capacitive sensors are used in almost all modern displays, originally touch. Wave touchscreens, as mentioned above, are used in banking, industrial, medical and other specific equipment. Thanks to the enterprising Chinese, they are also interesting when converting an ordinary monitor into a touchscreen.

It should be noted right away that the conversion of a conventional monitor into a capacitive touchscreen is no longer necessary: ​​such touchscreens are relatively expensive, specific and almost never found separately. But resistive and wave technologies are much more interesting in this regard. It is also worth mentioning the purely light (not PSV, but infrared) option.

Method 1: Luminous

The first way is the easiest and most affordable, but it requires certain skills and a desire to work. Before,how to make a touchscreen monitor, you need to stock up on a webcam, an infrared diode (like in a TV remote control), a piece of film (not developed), a battery and a case for a homemade stylus (a laser pointer is suitable, for example), as well as the Community Core Vision program. What to do with all this goodness - in more detail and on the points below.

Before, how to make a normal monitor touchusing this method, you need to make sure that the level of technical skills is sufficient, and the environment does not interfere with the realization of the idea. After all, the webcam needs to be precisely positioned, and for this you need a place on the table, which not everyone has. In addition, a slight shift of her or the screen forces you to set everything up again.

The method is cheap: from the equipment you will only have to buy the cheapest camera for 500 rubles (most already have it), an IR diode (you can pull it out of a broken remote control), a laser pointer (you can take a marker or other thin tube instead), batteries ( "mini-fingers" or "pills"). The most difficult thing is with photographic film: most people last held film "soap dishes" in their hands more than 10 years ago. In addition, the disadvantages of the method are the difficulty of setting, the instability of the design, and not the highest level of convenience.

Some Chinese manufacturers offer ready-made solutions of this type, allowing you to make the monitor touch. Such products are a special wide-angle webcam attached to the display and a stylus. This option is not without the mentioned shortcomings, but it looks attractive and does not require skills in working with homemade products.

Method 2: Wave

On sale there are ready-made touch panels that work on the principle of surface light (PSV) and surface acoustic (SAW) waves. They are glass with a frame, to which a special controller with a USB or COM (RS-232) interface is connected. Such solutions are intended primarily for the creation of terminals and special equipment, but no one forbids using them at home.

The process of altering the display with them is extremely simple.

1. Before, how to make a touchscreen monitor, you need to wipe it with a microfiber cloth with a special cleaner or an all-purpose glass cleaner. It is important to remember: if the screen has an anti-reflective coating, you cannot use products containing ammonia (ammonia) for this, as they wash off this layer!
2. After that, a touch glass is applied to the screen, which is fixed with the accessories included in the kit or put on high-quality double-sided tape (but it’s better to screw it on anyway).
3. The further setup procedure consists in installing a proprietary driver and other software (supplied on a disk with a sensor or downloaded from the manufacturer's website) and calibrating the touchscreen.

The main disadvantage of such a conversion of the monitor into a touchscreen is the relative high cost. A new sensor costs from several thousand to tens of thousands of rubles, depending on the diagonal. In addition, it is often difficult to find the right size for modern widescreen large diagonal matrices. This is due to the fact that narrow-format (4:5 or 3:4) screens have a better ratio of diagonal and usable area, so such touchscreens are produced for them more often. In addition, framed glass can ruin the aesthetics of a monitor by not blending in with its exterior.

Method 3: Resistive

In terms of price, efficiency and ease of use, the resistive touchscreen is the most preferable. Chinese manufacturers create special touch films of different levels of accuracy, durability and functionality, with different sizes.

Some of them can be cropped to fit the display dimensions, while others do not support such modification. Therefore, before you buy such a touchscreen, you need to study its description and characteristics.

1. Before, how to make a normal monitor touch, it also needs to be wiped from dust and stains.
2. Next, you should remove the front frame from the screen (usually this is done using a pick, an unnecessary bank card or other thin object made of durable plastic that is inserted into the gap) and wipe the display again with microfiber.
   
3. If the touchscreen does not fit, but supports cropping, you need to take measurements from the matrix in order to fit the sensor to it. This must be done in accordance with the sensor manufacturer's instructions. It is also recommended to watch the video instruction for disassembling the display, so as not to accidentally break it. Finally, it's important to remember that modification will void your display manufacturer's warranty.
4. Along the edges of the monitor matrix (outside the visible area), you need to stick special gaskets on which the touch will be placed. This is required to protect the display from finger pressure during operation.
5. Next, you need to position the sensor and stick it on top of the matrix.
6. To hide the touchscreen controller and secure it, you need to remove the back cover of the monitor. To do this, you need to disconnect the leg or stand, unscrew the screws at the back (if any).
   
7. Near the scaler board (matrix controller), it is desirable to find a free place where the controller will be placed on a screw or double-sided tape (the first option is more reliable).
8. The controller's power and data cable must be led into the existing hole near the VGA / HDMI / DVI connector or other connection interface. If there is no hole, it can be made with a drill or with a hot nail (choose the diameter according to the thickness of the cord).
   
9. When installing the controller, it is important to monitor the integrity of the cable, preventing it from twisting, sharp bends, etc.
10. If the matrix fits snugly into the monitor case - in the place where the cable will go back, it is better to make a file on the case with sandpaper, a needle file, or remove a layer of plastic with a hot knife.
11. Then the back of the case can be put back on.
12. To get the monitor frame back, it will have to be modified. Depending on the design features, you will have to file the fasteners, cut off or grind off the inner sides a little, etc. After fitting it can be installed.
    
13. The final step is to connect the sensor and calibrate it. To do this, you need to install a driver (downloaded from the sensor manufacturer's website or supplied on a disk), and then adjust the accuracy by touching the points that the driver program displays on the screen.