The difference between single layer multi point and double layer stackup of touch screen

Touch screen is also known as:"Touchscreen"、"Touch panel"It is an inductive liquid crystal display device that can receive input signals such as contacts, when touching the graphic button on the screen, the haptic feedback system on the screen can drive various connection devices according to the pre-programmed program, capacitive screen expert, the number of 183, the middle four digits are 2005, and the last four digits are 9375. All touch.

It can be used to replace the mechanical button panel, and create vivid audio and video effects through the LCD screen. As the latest computer input device, touch screen is currently the simplest, most convenient and natural way of human-computer interaction. It gives a new look to the multi-first, and is a very attractive new multi-interactive device.

It is mainly used in public information inquiry, leadership office, industrial control, military command, video games, song and food, multi-class teaching, real estate pre-sale, etc.

The single-layer structure of the touch screen can also be realized at multiple points, such as the single-layer of the capacitive screen, a layer of glass and ITO, etc., which can produce touch.

The other is a 2-layer capacitive screen G+G structure, which is called a projected capacitive screen, which can support 10-point touch.

Types: Touch screens can be divided into five basic types from the technical principle: vector pressure sensing technology touch screen, resistance technology touch screen, capacitive technology touch screen, infrared technology touch screen, surface acoustic wave technology touch screen.

Among them, the touch screen of vector pressure sensing technology has withdrawn from the stage of history; Infrared technology touch screen** is cheap, but its outer frame is fragile, easy to produce light interference, and distortion in curved cases; The design of capacitive technology touch screen is reasonable, but the problem of image distortion is difficult to be fundamentally solved. The positioning of the resistive technology touch screen is accurate, but its ** is quite high, and it is afraid of scratching and fragile damage; The surface acoustic wave touch screen solves the various defects of the previous touch screen, which is clear and not easy to be damaged, and is suitable for various occasions, but the disadvantage is that if there are water droplets and dust on the surface of the screen, the touch screen will become sluggish, or even not work.

The structure introduces the capacitive screen

The structure of the capacitive touch screen is mainly to coat a transparent film layer on the glass screen, and then add a protective glass outside the conductor layer, and the double glass design can completely protect the conductor layer and the sensor.

Capacitive touch screens are plated with narrow electrodes on all four sides of the touch screen to form a low-voltage alternating current field in the conductive body. When touching the screen, due to the electric field of the human body, a coupling capacitance will be formed between the finger and the conductor layer, and the current emitted by the four electrodes will flow to the contact, and the current strength is proportional to the distance from the finger to the electrode, and the controller behind the touch screen will calculate the proportion and strength of the current to accurately calculate the position of the touch point. The double glass of the capacitive touch screen not only protects the conductor and sensor, but also prevents external environmental factors from affecting the touch screen, even if the screen is stained with dirt, dust or oil, the capacitive touch screen can still accurately calculate the touch position.

Since the capacitance changes with temperature, humidity or grounding, it is not stable and tends to drift. This touch screen is suitable for the commissioning phase of system development.

The difference between the double-layer winding and the single-layer winding of AC motors is that the components are placed differently, the functions are different, and the characteristics are different.

1. The placement of components is different: only one component edge is placed in a slot in a single-layer winding, and two component edges are placed in a slot in a double-layer winding.

2. Different functions: double-layer windings that cannot be completed by single-layer windings can be done, such as fractional slots, pole changes, etc.

3. Different characteristics: less single-layer winding coil, relatively simple process; There is no interlayer insulation, so the utilization rate of the groove is high; The single-layer structure does not suffer from phase-to-phase breakdown failures. The disadvantages are:

The electromagnetic waveform generated by the winding is not ideal, the iron loss and noise of the motor are large and the starting performance is slightly poor, so the single-layer winding is generally only used in small-capacity asynchronous motors.

The advantages of double-layer windings are that suitable short-distance windings can be selected to improve the electromagnetic waveform, and fractional slot windings can be used to weaken higher harmonics. After using double-layer winding, the electromagnetic performance, force energy index and starting characteristics of the motor are better than those of single-layer winding. Two coil element edges are embedded in each groove in the core groove of the double-layer winding, when one coil edge of the coil element is embedded in the lower layer of a certain groove, and its other coil edge is placed in the upper layer of the other groove, the double-layer winding has two kinds of stacked winding and wave winding.

1. Relatively speaking, the double-layer winding that cannot be completed by a single layer winding can be done for special needs, such as fractional slots, pole changes, etc.

2. Relatively speaking, the double-layer winding is more wire-saving.

3. When the critical low voltage, the double-layer winding can start, while the single-layer winding cannot start.

4. The upper and lower windings of the double-layer winding are sometimes not necessarily one phase, relatively speaking, the interphase insulation is not as good as the single-layer winding.

5. The single-layer winding is 1 side of each coil embedded in each slot, and the double-layer winding is 1 side of each of the 2 coils embedded in each slot.

The double-layer winding is a short pitch, which can facilitate the pole change connection.

Single-layer double-layer is said to be placed in the slot of the winding is to put a layer of winding or two layers, we often say that the stacked wave winding is double-layer that has been, you can refer to the figure, the single-layer can be said to be simple structure, convenient winding, double-layer utilization rate will be higher, more convenient to use favorable pitch, and the windings are the same convenient to manufacture, heat dissipation is also beneficial, so the range of use is more extensive.

The main part of the resistive touch screen is a resistive film screen that is very compatible with the surface of the display, which is a multi-layer composite film, which uses a layer of glass or hard plastic plate as the base layer, and the surface is coated with a transparent oxide metal conductive layer, which is covered with a layer of outer surface hardening, smooth and anti-rub plastic layer, and its inner surface is also coated with a layer of ITO coating, and there are many small transparent isolation points between them to separate the two layers of conductive layer from insulation.

When a finger touches the screen, the two layers of conductive layers come into contact at the touch point, and the controller detects this contact and calculates the position of (x,y), which then works in a way that simulates a mouse.

A resistive touch screen is a sensor that converts the physical position of a touch point (x,y) in a rectangular area into a voltage that represents the x and y coordinates. Many LCD modules use resistive touch screens that can be used with four, five, seven, or eight wires to generate the screen bias voltage and read back the voltage of the touch point.

Detailed explanation of classification

Four-wire touch screen.

The four-wire touchscreen contains two resistive layers. One of the layers has a vertical bus on the left and right edges of the screen, and the other has a horizontal bus at the bottom and top of the screen. For measurements in the x-axis direction, the left bus is offset to 0V and the right bus is biased to VREF.

Connect the top or bottom bus to the ADC and take a measurement when the top and bottom layers come into contact.

Five-wire touch screen.

The five-wire touch screen uses a resistive layer and a conductive layer. The conductive layer has a contact, usually at the edge of one of its sides. The resistive layer has one contact at each of the four corners.

Seven-line touch screen.

The implementation method of the seven-line touch screen is the same as that of the five-line touch screen except for adding a line in the upper left corner and the lower right corner. Grasp.

Eight-wire touch screen.

Except for adding one wire to each bus, an eight-wire touchscreen is implemented in the same way as a four-wire touchscreen.

This is the difference between capacitive screen and resistive screen.

One is judged by the feeling of pressure on your fingers. One is to be sensed by the current of the human body itself from your fingers. That's why it's a big difference.

Detailed**.

Single-layer glass is a layer of glass, which is not sound and heat insulation, but it is cheap. Double-layer glass is sandwiched in the middle of the double-layer glass with a layer of dry air, and then sealed, with the effect of heat and sound insulation, the insulating glass is two or more pieces of glass edges sealed together, between the glass to form a static dry gas, and there is a certain vacuum performance, in the sealing of the balcony many people choose such glass windows, ** is definitely higher than the single-layer glass.

Theoretically, the sound and heat insulation effect of double-layer glass is better than that of a single layer, but it actually depends on the quality of the things made by the manufacturer. The affordable point is still a single layer, the plastic steel heat insulation and sealing effect is better, the durability is poorer, and the better one can use broken bridge aluminum. This involves the quality of the window itself, as well as the construction problem, if the window seam, the closed part of the seal is not handled well, the double layer is also in vain.

In addition, the weight of the double layer is much heavier, and the safety of the window sill should also be considered.

There is a difference in heat preservation: there are three main ways of heat propagation: conduction, convection, and radiation.

Double-layer glass mainly relies on the sealing of the middle of the two layers of glass, reduces air convection and conduction, blocks the two modes of transmission, and avoids heat dissipation, while single-layer glass is not good, and now there are many insulation materials in the building materials market, including walls, ceilings, doors and windows, etc.

Single-layer glass is not enough for sound and heat insulation, but it is cheap. Double glazing is a layer of dry air sandwiched in the middle of the double glazing, and then sealed, with the effect of heat and sound insulation. The warmth of double-glazed glass should be twice as good as that of single-glazed insulation.

Double glazing.

It refers to insulating glass (linked insulating glass), which is a composite glass product composed of two pieces of glass. Single-glazing is easy to understand.

Compared with single-glazing, double-glazed glass can save up to 32% of energy

That's a lot. In the northern region. The single-layer glass will freeze in the north, and the double-layer will not freeze no matter how cold it is.

Double-glazed insulation should be twice as high as single-glaze insulation.

1. The production process is different

The production process of single-layer tents is relatively simple;

Double-decker tents add a layer of air permeability to the design of single-decker tents. The outer tent is waterproof and windproof, and the inner tent is breathable; The heat emitted by the human body will pass through the inner tent, condense on the inner wall of the outer tent, and then slide down the inner wall of the outer tent to the gap between the outer tent and the inner tent, so that the sleeping bag will not be wet.

2. The volume operation is different

Single-layer tents are lightweight, small in size, and occupy a small area, making them easy to set up;

Double-decker tents are larger in size, take up more space when folded, occupy a larger area, and are more cumbersome to build;

3. The use environment is different

Single-layer tents: summer camping activities such as park leisure and beach leisure, generally do not spend the night outdoors, ** relatively cheap; Due to its light weight, it is also used for snowy mountain climbing, but it requires the use of high-tech functional fabrics and accessories, which is more expensive.

Double-layer tent: a wide range of uses, three seasons and four seasons tents are mostly double-layer structure, cost-effective.

A single layer is made of only one layer of cloth; The other layer is made of two layers of cloth. Is it better to have a single or double layer? - Each has its own benefits:

The advantage of a single layer is that it is light when it is dispatched, and it is labor-saving when riding; The disadvantage is that the anti-freezing effect is poor, and the thermal effect is poor. The advantages of double layer are -- good freezing effect, good heat effect; The disadvantage is that it is inconvenient to carry when dispatching, and it is laborious when riding, and the bracket should be stronger than the single-layer one.

Hearing you ask, you must have never used a tent. The double-layer tent has a good rainproof effect, and the single-layer one is basically useless if the rain is relatively heavy. However, if it's an occasional outing, I personally don't recommend buying a tent.

A few days ago, I camped and rented a tent at an outdoor shop for only 15 yuan a day. In addition, in addition to being in a mood, sleeping in a tent is really sinful, very stuffy, there are more mosquitoes at night, and it is definitely not good to rest. If you have your own home, it is recommended to rent one for a try before deciding whether to buy it or not.

Travelers are a different matter and are beyond the scope of my remarks.

The difference between whether it can be waterproof or not, single-layer generally cannot be waterproof.

Wave tent combined with experience sharing.

1. Single-layer tent.

The production process of single-layer tent is relatively simple, and its larger characteristics are lightweight, economical, and small in size, which is suitable for everyone to carry when traveling.

2. Double-decker tents.

The difference between the double layer and the single layer is that a layer of air permeability is added to the design. In the cooler season, the heat excreted by the human body will condense water droplets on the inner wall of the tent under the action of the air outside the tent, and if it is a single-layer tent, the water droplets will flow down the inner wall of the tent and wet the sleeping bag. After the inner tent is added, the outer tent is not directly connected with the inner tent, and the heat emitted by the human body will pass through the inner tent, so that the water droplets condensed in the outer tent flow into the ground, which solves the problem of water formation on the inner wall of the single-layer tent.

It is a good choice for places where there is a lot of dew at night.

The first layer is very thin, and the function is to gently lift the beard, and the second layer is to shave the beard by the roots, so that the deep shave is cleaner and more thorough.

The shaver double blade technology is cleaner than the single blade technology, the single blade has only one layer, and the double blade is two layers on top of each other, so the double blade is cleaner.

It is recommended that it is best to buy the knife head that can be disassembled, and go to a regular place to buy, the physical store has seen and touched the real thing is more real, and it is cheap to buy fakes online. It is impossible to tell the truth from the head alone, and the function is to gently lift the beard.

Depending on the individual's beard and **, the direction of choosing a razor is also different. First of all, look at the density and hardness of the beard, many and dense shavers need three heads, and a younger general double head will do. The double-layer blade upgrade is also something to consider when you need to buy it again.

Nowadays, young people generally use double-layer blades more. And there are many varieties of so-called waterproof, double-headed and so on on the market, depending on personal preferences and understanding of this thing, of course, ** is also a big gap, for reference.