The function of sensor in mobile phone
The role of sensors in mobile phones, many electronic devices need to use sensors, many people do not know much about sensors, sensors are a kind of detection equipment, can feel the measured information, can share the role of sensors in mobile phones.
The function of sensor in mobile phone 1 1, ambient light sensor.
Optical sensors are similar to the eyes of mobile phones. The human eye can adjust the light entering the eye in different light environments. For example, when entering a cinema, the pupil will be enlarged to allow more light to enter the eye. The light sensor allows the mobile phone to sense the intensity of ambient light to adjust the brightness of the mobile phone screen.
Because the screen is usually the most power-consuming part of the mobile phone, the use of light sensors to help adjust the brightness of the screen can further extend the battery life. The optical sensor can also be used with other sensors to detect whether the mobile phone is put in the pocket to prevent accidental touch.
2. Proximity sensor
The infrared ray emitted by the infrared LED lamp is reflected by the object and then received by the infrared detector, so as to judge the intensity of the received infrared ray and the distance. The effective distance is about 10 meter. It can sense whether the phone is attached to the ear to make a call, and if it is, it will turn off the screen to save electricity; The distance sensor can also be used in glove mode supported by some mobile phones to unlock or lock the mobile phone.
Location of distance sensor and optical sensor for iPhone 4/4s and iPhone 5/5s
3. Gravity sensor (gravity sensor)
Through the piezoelectric effect. There is a weight in the gravity sensor integrated with piezoelectric sheet, and the horizontal direction can be calculated by the voltages generated in two orthogonal directions. When it is used in a mobile phone, it can be used to switch between landscape screen and portrait screen. When used in racing games, it can rotate the driving direction by sensing in the horizontal direction and using the data in the game.
4. Acceleration sensor
The principle of action is the same as that of gravity sensor, but the acceleration direction is determined by three dimensions, with low power consumption but low accuracy. Used in mobile phones, it can be used to count steps and judge the direction of mobile phones.
5. Magnetic sensor
Measuring the change of resistance to determine the magnetic field strength requires shaking the mobile phone to accurately judge, which is mostly used for compass and map navigation.
6. Gyroscope
Gyroscope can measure the angular velocity along one axis or several axes, which is an ideal technology to supplement the function of MEMS accelerometer. In fact, if you combine an accelerometer with a gyroscope.
System designers can track and capture the complete action of three-dimensional space, and provide more realistic user experience, accurate navigation system and other functions for end users. The "shake" function in the mobile phone (for example, shake the mobile phone to draw lots ...), somatosensory technology, and the adjustment and detection of VR viewing angle are all applied to the gyroscope.
7、GPS
There are 24 GPS satellites running in a specific orbit above the earth, and they will continuously broadcast their position coordinates and time stamps to all parts of the world (referring to the total number of seconds from Greenwich Mean Time197001kloc-0/0000 minutes and 00 seconds).
Starting from the instantaneous position of the satellite, the GPS module in the mobile phone calculates the distance between the mobile phone and the satellite through the time stamp of the satellite transmitting coordinates and the time difference when receiving. It can be used for positioning, speed measurement, ranging and navigation.
8. Fingerprint sensor
At present, the mainstream technology is capacitive fingerprint sensor, but ultrasonic fingerprint sensor also has a trend of popularization. When the capacitive fingerprint sensor works, the finger is one pole of the capacitor and the other pole is the silicon chip array.
The fingerprint pattern is drawn by the micro-current generated between the micro-electric field carried by the human body and the capacitance sensor, and the distance between the peak and valley of the fingerprint and the sensor forms the capacitance difference. The principle of ultrasonic fingerprint sensor is similar, but it will not be interfered by sweat and oil, and the recognition speed is faster. Can be used in mobile phones to unlock, encrypt, pay and so on.
9. Hall sensor
The principle of action is Hall magnetoelectric effect. When current passes through a conductor in a magnetic field, the magnetic field will generate a force perpendicular to the direction of electron movement, thus generating a potential difference across the conductor. It is mainly used for flip unlocking, screen locking and other functions. Apple's Smart cover and official mobile phone accessories of several brands have adopted this technology.
10. Barometer
Connect the diaphragm to the sensor or capacitor. When the air pressure changes, the value of resistance or capacitance will change, thus measuring the air pressure data.
GPS can also be used to measure altitude, but there will be an error of about 10 meter. If equipped with air pressure sensor, the error can be corrected to about 10 meter. It can also be used to assist GPS positioning and confirm floor location and other information. Apple's iPhone 6/6s series are equipped with air pressure sensors.
1 1, heart rate sensor
When the finger is illuminated by a high-brightness LED lamp, when the blood is pumped to the capillaries by the heart, the brightness (the depth of red light) will change periodically. Then these regular changes are captured by the camera and sent to the mobile phone for calculation, so as to judge the contraction frequency of the heart and get the number of beats per minute.
There is a heart rate sensor next to the Samsung Galaxy S7 edge camera.
12, blood oxygen sensor
Hemoglobin in blood and oxygenated hemoglobin have different absorption rates of red light. The infrared light and red light LED are used to irradiate the finger at the same time, and the absorption spectrum of the reflected light is measured, thus measuring the oxygen content in the blood. Can be used in the field of sports or health.
13, ultraviolet sensor
The photoelectric emission effect of some semiconductors, metals or metal compounds will release a large number of electrons under ultraviolet irradiation, and the ultraviolet intensity can be calculated by detecting this discharge effect. The main application is also in the field of sports and health.
On the whole, most of the first seven sensors are standard on smart phones, and fingerprint sensors are becoming more and more popular. Rear sensors are more common in smart bracelets and top-end and high-end mobile phones. Through the function of these sensors, we can make the mobile phone have more functions than you and I imagined, just like making the mobile phone more and more intelligent, don't you think?
The role of sensors in mobile phones 2 1, GPS position sensor
The main function of GPS module is to receive the coordinate information of satellite through antenna to help users locate. With the popularity of 4G network, GPS is applied in more scenarios, such as remote location monitoring with intelligent hardware, or location finding after equipment is lost.
Here, we need to distinguish a concept. Generally speaking, mobile phones come standard with A-GPS. The so-called A-GPS is more advanced than ordinary GPS, because it can quickly locate through the mobile network on the basis of receiving navigation satellite signals.
2. Distance sensor
The distance sensor is usually placed next to the mobile phone to detect the distance between the front of the mobile phone and other objects. If the distance reaches a threshold, it will automatically turn off the screen, saving electricity and preventing misoperation of the touch screen of the mobile phone.
Usually, distance sensors are used in two ways on mobile phones. First, when the mobile phone is close to the head, it will automatically close the screen to prevent the ear or face from misoperation of the touch screen.
Moreover, turning off the screen during the call can save electricity, and the mobile phone will automatically light up when it is taken away from the ear; The second is to prevent the mobile phone from misoperation when the screen is lit in the pocket or bag. When the distance sensor senses an object at close range, it will inform the mobile phone to automatically close the screen.
3. Air pressure sensor
Air pressure sensors have been used in military mobile phones before, which are divided into variable volume air pressure sensors and variable resistance air pressure sensors. The change of air pressure will lead to the change of resistance or capacitance measurement.
Generally, GPS can calculate your position, but for some height changes, air pressure sensors are needed to measure it. The mobile phone equipped with this sensor can measure how many floors you go to a day, or it can be used for indoor positioning. The internal air pressure sensor mainly tests the sealing degree of the equipment.
4. Light sensitive element
Smartphones usually have such a setting-automatic brightness level. When turned on, the phone will automatically adjust the screen brightness according to the intensity of surrounding light. In sunny outdoor, the brightness of the screen will automatically increase to help people see the screen clearly under strong light;
In the dark night, the brightness of the screen will automatically decrease, reducing the stimulation of light to the eyes and saving electricity by the way. Optical sensor is used to feel the intensity of the surrounding light to realize the automatic adjustment of the screen brightness of mobile phone.
The light sensor and the distance sensor are often integrated in one place, which can reduce the opening of the front panel and make the design look better. Since T 1, the well-known hammer mobile phone has integrated the light sensor, distance sensor and earpiece into a long opening, and the front panel is more unified.
The role of sensors in mobile phones 3 1, what is a sensor?
A sensor refers to a component or device that converts the collected information into a signal that can be processed by the device. Humans will act according to the information obtained by sight, hearing, smell and touch, and so will devices, which will control or process according to the information obtained by sensors.
The sensor collects the converted signals (physical quantities) such as temperature, light, color, air pressure, magnetic force, speed and acceleration. , using the material change of semiconductor. In addition, there are biosensors using biological substances such as enzymes and microorganisms. There are many kinds of sensors, about 30 thousand or more.
A thorough understanding of sensors spans almost all manufacturing categories, and it is as difficult as identifying the stars in the sky. Common sensor types are: temperature sensor, humidity sensor, pressure sensor, displacement sensor, flow sensor, liquid level sensor, force sensor, acceleration sensor, torque sensor and so on.
2. How important is the sensor?
Sensors are at the forefront of all industrial products, which provide the first barrier to perceive the physical world. These sensors provide real-time monitoring, including detection and reporting required by the process.
The data monitored and collected by the sensor is sent for control and analysis, and any abnormality in a specific attribute is reported by the sensor sending out an electrical signal. In this way, sensors can improve process efficiency and product quality, while ensuring that the process conforms to best practices. Therefore, without many excellent sensors, modern production will lose its foundation.
The main features of the sensor include: improving the sensitivity of data acquisition, almost lossless transmission and continuous real-time analysis. Real-time feedback and data analysis services can ensure that the process is active and executed in the best way.
The continuous development of sensing technology has given birth to today's intelligent sensors. Unlike traditional analog sensors without active components, smart sensors contain circuits that can measure and output digital data. These sensors have embedded microprocessor units, and many sensing devices are mounted on signal converters.
Smart sensors can perform many internal intelligent functions, such as self-test, self-verification, self-adaptation and self-identification. They understand process requirements, manage various conditions, and can detect conditions to support real-time decision-making. These smart sensors are programmed for various process conditions so that managers can get the maximum benefit.
China, the United States, German and other countries have listed sensors as major scientific and technological projects in the future, and achieving technological breakthroughs in sensors is enough to illustrate its importance. The World United Chamber of Commerce even commented that whoever dominates the sensor will dominate the new era.
3. The sensor market maintained rapid growth.
From 20 12 to 202 1, China's industrial added value increased from 20.9 trillion yuan to 37.3 trillion yuan; Calculated at constant prices, the industrial added value grew at an average annual rate of 6.3%, much higher than the average annual growth rate of the global industrial added value of about 2% in the same period; The added value of manufacturing increased from 16.98 trillion yuan to 310.4 trillion yuan, accounting for nearly 30% of the global total.
The Internet of Everything and the rapid increase of industrial added value are inseparable from the support of powerful sensors. In the information age, sensors are widely used in industrial production, ocean exploration, environmental protection, resource investigation, medical diagnosis and other fields.
By 2025, the economic benefits brought by the Internet of Things will be between 2.7 trillion and 6.2 trillion US dollars, among which sensors, as the most important data acquisition entrance of the Internet of Things technology, will usher in a broad development space.
China's strategy of building a powerful country is also inseparable from the support of powerful sensors! According to the data of China ICT Institute, China's sensor market has maintained rapid growth in recent years, and it has maintained growth in 20 19. The overall market scale reached 2188.8 billion yuan, a year-on-year increase of 12.7%. In 20021year, the market scale reached 29510.80 billion yuan, with a growth rate of 17.6%.