Principle of Occupancy Sensor The working principle and application of infrared occupancy sensor

The core element of the infrared human body sensor is a pyroelectric sensor, which detects the infrared radiation of the human body or animals from the environment to determine whether there are people or animals within the detection range, and is often used in smart homes to determine whether people have passed by, or in intelligent security to determine whether there are suspicious people intruding into the defense area.

Take the Linkp human infrared sensor as an example to give you a specific application scenario, place it in a corner under the bed, link the smart switch through the gateway, set the execution conditions from 10 pm to 6 am, when you perceive that someone is getting up and moving, turn on the bedside lamp, and automatically adjust the light, and you don't have to find the switch in the dark at night.

The working principle of the infrared sensor is that the pyroelectric element will release an electric charge when the temperature changes after receiving infrared radiation, and an alarm will be generated after detection and processing.

Infrared sensor is a kind of sensor that uses infrared rays to process data, which has the advantages of high sensitivity, and the infrared sensor can control the operation of the driving device. Infrared sensors are commonly used for non-contact temperature measurement, gas composition analysis, and non-destructive testing, and are widely used in the fields of medicine, military, space technology, and environmental engineering. For example, thermal imaging of the surface temperature of the human body using an infrared sensor to measure the surface temperature of the human body from a distance can detect abnormal temperatures.

The infrared sensor does not have direct contact with the measured object during measurement, so there is no friction, the application environment temperature is not demanding, and it has the advantages of high sensitivity, fast response and wide spectral response.

This is through the principle of infrared reflection, when the human hand or a certain part of the body is in the infrared region, the infrared rays emitted by the infrared emitting tube are reflected to the infrared receiving tube due to the human hand or body blocking, and the signal processed by the microcomputer in the integrated circuit is sent to the pulse solenoid valve, and the solenoid valve opens the valve core according to the specified instruction to control the head water after receiving the signal; When the human hand or body leaves the infrared sensing range, the solenoid valve does not receive a signal, and the solenoid valve core is reset by the internal spring to control the water shut-off.

The wavelength of infrared light in the spectrum from 400 microns is called infrared, and infrared is invisible light. All substances above absolute zero () can produce infrared light. Modern physics calls this a heat ray.

Medical infrared can be divided into two categories: near-infrared and far-infrared.

Infrared sensor.

Solar spectrum. Infrared is one of the many invisible rays of the sun's rays, discovered by the German scientist Hoxel in 1800, also known as infrared thermal radiation, he used a prism to break down the sunlight, placed a thermometer on the position of the color band of various colors, trying to measure the heating effect of various colors of light. It turned out that the thermometer on the outside of the red light warmed up the fastest. Hence the conclusion:

In the solar spectrum, there must be invisible light on the outside of the red light, which is infrared. It can also be used as a medium of transmission. The wavelength of infrared rays on the solar spectrum is greater than that of visible light, and the wavelength is.

Infrared can be divided into three parts, namely near-infrared, with a wavelength of (between; Mid-infrared, wavelength (between; Far infrared rays with wavelengths between (25-40) l000 m.

A true infrared night vision device is photomultiplier tube imaging, which is completely different from the principle of a telescope, cannot be used during the day, is expensive and requires a power supply to work.

Near-infrared rays or short-wave infrared rays, with a wavelength of microns, penetrate deep into human tissues, about 5 10 mm; Far infrared rays or long-wave infrared rays, with a wavelength of microns, are mostly absorbed by the surface layer**, and penetrate the tissue to a depth of less than 2 mm.

Development process. The automatic control system can complete certain tasks according to the design of the human and without the participation of the human being. The key lies in the introduction of feedback, which is actually the output or state of the system, added to the input of the system and the input of the system to act together on the system. The output state of the system is actually various physical quantities, some of them are voltage, some are flow, velocity, etc.

These quantities are often different in nature from the inputs to the system, and have different ranges of values. Therefore, it cannot be directly combined with inputs, but needs to be measured and converted. The sensor plays this role, it is like the eye of the control system, perceiving various changes in the control system, and cooperating with other parts of the system to complete the control task.

The principle of infrared induction is to use the feeling of light and the temperature of other objects to judge whether the object is an animal, what kind of animal is a plant, and the temperature is higher.

The principle of infrared reflection, when the human hand or a certain part of the body is in the infrared region, the infrared rays emitted by the infrared emitting tube are reflected to the infrared receiving tube due to the human hand or body, and the signal processed by the microcomputer in the integrated circuit is sent to the pulse solenoid valve, and the solenoid valve opens the valve core according to the specified instructions to control the head water after receiving the signal; When the human hand or body leaves the infrared sensing range, the solenoid valve does not receive a signal, and the solenoid valve core is reset by the internal spring to control the water shut-off.

The principle of the infrared sensor is through its heat, through which it is included in the heat, and it can be directly activated through the air.

That should be good, the communication of the secondary processing you deal with is different.

Principle: The infrared induction source usually uses pyroelectric components, which will lose the charge balance and release the charge when the temperature of the infrared radiation of the human body changes, and the subsequent circuit can generate an alarm signal after detection and processing.

How to use: Adjust the concentric ring and the infrared probe to have a proper focal length, the infrared light is just received by the probe, and the probe will turn the optical signal into a bridge banquet signal and send it into the electronic circuit to drive the load to work. The infrared sensor should be kept away from air conditioners, refrigerators, stoves and other places where air temperature changes are sensitive.

I'm glad about your question, and then let's talk about the specific use scenarios with the Linkp human infrared sensor. When a person passes in front of the Linkshop body sensor, the infrared energy focused on the pyroelectric sensor will be constantly changed and amplified to achieve higher accuracy of human movement detection.

Before installation,We can first connect it to the smart home inspection ecological platform,Lingpu human infrared sensor supports Xiaomi Mijia ecological platform,It can be directly connected to Xiaoai speaker access to Mi Home,Linkage with other smart devices。 When installing, it is necessary to choose a good position in advance, its main role is to detect the existence of the human body, to achieve linkage scenes, such as switching lights, etc., so it should be placed in a position where people move more frequently, and it is recommended to put a distance of 1-2 meters on the wall at a height. With a 120° sensing range and an 8-meter detection distance, the Lingpu Human Infrared Sensor can cover areas such as entrances, balconies, and living rooms, and it is also equipped with a 90° foldable 360° rotating base, which can also flexibly adjust the detection position after being on the wall.