On the phone those unknown sensor
Now mobile phone is more and more, especially the development of mobile Internet, mobile phone progress more quickly. For the requirement of the mobile phone is no longer confined to previous calls and text messages, we demand for mobile phones on the function also more and more. Now the mobile phone in order to implement different functions, to plant a lot of sensors, and these sensors and how did their job? In this paper, on a variety of sensors are introduced.
An acceleration sensor (accelerometer)
Acceleration sensor is an electronic device that can measure the acceleration. In the mobile phone, an acceleration sensor can be used to detect cell phone by the size of the acceleration and direction. Acceleration sensor principle: using piezoelectric effect, a "gravity" and made a piezoelectric crystal gravity induction module, mobile direction changes, gravity block with the force acting on different direction of piezoelectric crystal is changed, the output voltage is different, so as to determine the direction of the mobile phone. Gravity induction is often used in automatic rotary screen and some of the game, but its limitations is bigger, because he is according to the gravity direction, through the induction of gravity orthogonal component size in two directions, to determine the horizontal direction.
The distance sensor
Distance is induced by issuing infrared light, when the object is close to, return the infrared light is detected element, then you can judge the object close to the distance. Distance induction usually use automatically shut down after the phone on the screen, now most of the touch screen mobile phone will have this function, online rumours that don't use touch screen mobile phone "big face" is clearly unreliable. In addition, some mobile phone film will keep out distance sensor, affect the work, so it is important to pay special attention to.
Air pressure sensor
Before air pressure sensor, the author has already had a relevant measurement. Air pressure sensor's work is through a membrane element is sensitive to the pressure, film connecting a flexible resistance, when atmospheric pressure change, will cause the resistance tolerance changes. The role of pressure sensor is mainly used for detecting atmospheric pressure, the current height and assisted GPS positioning.
The light sensor
The light sensor is composed of cast light modulator and by light, cast light will light the focus and the transfer to the light, finally through a receptor into electrical signals. Is the purpose of the light sensor can according to ambient light to adjust the brightness of the screen itself.
