Proximity Sensor and Its types

Proximity Sensor

Proximity Sensor is a sensor which is designed to detect the presence or absence of an object without any physical contact. Proximity sensor is provide a high-speed response, reliable for critical environment used because no contact with a target. Proximity sensors are used in various platform like process industries manufacturing industries, automobile industries, textile industries etc.

Types Of  Proximity Sensors

There are five types of common Proximity sensors  available in market  

1. Inductive Proximity Sensor
2. Capacitive Proximity Sensor
3. Magnetic Proximity Sensor
4. Ultrasonic Proximity Sensor
5. Optical Proximity Sensor

Inductive Proximity Sensor

An inductive Proximity Sensor is created electromagnetic field when the target came its electromagnetic field range then eddy current generate on target thus the magnetic field opposed the sensor electromagnetic field resultant the inductive characteristics of target is change then sensor output

presence of target.

       Inductive Proximity Sensor: sensing distance is 1mm to 60mm.Sensitivity of Inductive Proximity         Sensor is adaptable to harsh environments. It is capable to sensing the target material  is ferrous         metal.  It is low cost and small size sensor. It is used for Foil seal detection inside  plastic caps,               Counting of metal cans.

Capacitive Proximity Sensor

A Capacitive Proximity Sensors detect changes in the capacitance between the sensing target and the Sensor. A capacitive Proximity Sensor is similar to a capacitor with two parallel plates, where the capacity of the two plates is detected. One of the plates is the  sensor and another plate is target.

Sensing distance of Target is 1-35mm.Its vibration tolerance is excellent. Sensitivity of Capacitive Proximity Sensor is very sensitive to change in environmental conditions such as temperature and humidity. It can sensing any material of target. Capacitive Proximity Sensor used for conveyors,

workstation and robotics. It is available in market  medium price and small size. 

Magnetic Proximity Sensor

A magnetic proximity sensor  detect only permanent magnet. It is work on hall effect principle. When

the target near the sensor then the sensor produced higher potential across it circuit thus threshold

output set at high. Magnetic Proximity sensor  have other technology  used such as Variable reluctance, Reed switch and Giant Magneto Resistive Effect. Its Sensing distance of target is 1-80mm.Magnetic Proximity Sensor  tolerance of vibration is excellent. Sensitivity of Magnetic Proximity Sensor have  chance to magnetic interference. Magnetic Proximity Sensor target should be a magnetic material. Magnetic Proximity Sensor used for status open or close such as doors, windows in food processing factory. Magnetic Proximity Sensors are available in market  low price and small size. 

Optical Proximity Sensor

It is consist a optical transmitter and receiver. The transmitter send the signal witch is  form of light rays The light rays strike on the target and return back to the receiver.

There are three types of Optical Proximity Sensors.

1. Through-beam
2. Retro-reflective
3. Diffuser

Optical Proximity Sensor: sensing distance is 2mm to 30mm.Sensitivity of Optical Proximity Sensor is  sensitive to lubricant and dust. It is capable to sensing the target of any material except transparent material of target.  It is medium cost and small size sensor. It is used for optical liquid level indicator, heart rate indicator, Automatic soap dispenser, Automatic tap.

Ultra Sonic Proximity Sensor

It is consist of Transmitter and Receiver. The transmitter change electrical signal into ultrasonic sound wave signal and send to the target and sound wave return back then receiver receive it. Its Sensing distance of target is 1-1000mm.Ultra Sonic Proximity Sensor  tolerance of vibration is poor. Sensitivity of Ultra Sonic Proximity Sensor having temperature variations due to speed of  ultra sonic sound wave.  Ultra Sonic Proximity Sensor, target material is any material include transparent. Ultra Sonic Proximity Sensor used for robotic sensing,  Liquid level control, Counting of packet and people, Anti collision safety systems. Ultra Sonic Proximity Sensors are available in market  high price and small size.

FAQ

Can proximity sensor detect human?

Yes, Proximity sensor can detect human body.

Is IR sensor a proximity sensor?

Yes ,Infrared Sensor is act as proximity sensor, It is used in robot for obstacle detection and also used for measure the temperature of any target.

What is a proximity sensor on my phone?

Many smartphone have proximity sensors. The sensor automatically control it such as when smartphone display needs to increase brightness or decries brightness automatically by the help of sensor and also when you place your smartphone to your ear then display will be turning off.

if you remove phone from  your ear then the lighting up  of  phone screen.

What can an inductive proximity sensor detect?

Inductive proximity sensors can only detect metal targets. They do not detect non-metal targets. 

What does a proximity sensor sense?

A proximity sensor is a device that can detect or sense the approach or presence of nearby objects and for this it does not need any physical contact.