7 most popular types of sensors and practical applications

1. What is a sensor?

A sensor is a technical device designed to detect events or changes in specific environments such as light, heat, sound or pressure, and convert these physical data into electronic signals. These signals are then transmitted for analysis or processing for the purpose of monitoring, measuring or controlling activities in many different fields, from industry to consumer.

Definition of sensor

2. 7 common types of sensors

Proximity sensor

1. Electromagnetic proximity sensor: This is a sensor that uses an electromagnetic field to detect the presence of a metal object. When a metal object enters the range of the magnetic field, it will cause a change in the alternating current, thereby creating an output signal.
2. Ultrasonic proximity sensor: This type operates based on the principle of emitting and receiving ultrasonic waves. When the ultrasonic wave is emitted and comes into contact with the object, it will reflect back to the sensor. The distance to the object is determined by measuring the time between when the wave is emitted and when the wave is reflected.

1. Photoelectric proximity sensor (infrared): This type emits infrared rays and uses a sensor to measure the amount of infrared rays reflected back from the object. The distance and presence of the object are determined based on the level of reflection of the infrared rays, allowing the sensor to accurately measure the distance to the object.

1. Capable of detecting non-metallic and metallic objects without direct contact, allowing for flexible use in a variety of industries.
2. The detection distance can be adjusted up to 30mm, depending on the type and size of the object, ensuring flexibility in system design.
3. Designed to withstand environmental influences such as dust, humidity and high temperatures, ensuring high reliability and durability in industrial environments.
4. Integrated anti-electromagnetic interference technology, allowing the sensor to operate stably even in environments with the presence of strong interference signals.
5. Easy integration into automatic control systems, thanks to the simple connection interface and the ability to coordinate with PLCs and industrial computers.

1. Construction and infrastructure control: Proximity sensors can be used in infrastructure monitoring systems to detect signs of structural cracks or displacement, thanks to their ability to accurately detect changes in distance and position.
2. Packaging industry: In this industry, proximity sensors are used to ensure that products are packaged correctly, without overlapping or misalignment on the production line
3. Security and surveillance systems: Proximity sensors can be integrated into alarm systems to detect unwanted intrusion, by alerting when there is a change in distance or an object moves into a restricted area.
4. Entertainment and sports industry: Used in entertainment devices such as video games and simulators, to detect player movements and smooth interaction with the system.
5. Agriculture: Proximity sensors can be used to monitor and adjust the position of equipment in greenhouses or on agricultural packaging lines, ensuring the processing of agricultural products is automatic and accurate.
6. Medical industry: Proximity sensors are used in medical devices to detect the position of medical instruments in the body to limit accidents during surgery.

Temperature sensor

1. NTC Thermistor (Negative Temperature Coefficient): This type of sensor uses a semiconductor material whose impedance changes with temperature. NTC Thermistors decrease in impedance as temperature increases, making them suitable for accurate measurements within a narrow temperature range.

2. RTD (Resistance Temperature Detector) Sensor: Usually uses platinum wire, such as PT100 and PT1000, with basic impedances of 100 ohm and 1000 ohm at 0 degrees C respectively. RTD is famous for its high accuracy and stability over a wide temperature range.

3. Thermocouple: Uses two different metals to form a circuit, generating voltage when there is a temperature difference between two points. Type K and J thermocouples are two of the most common types, resistant to high temperatures and suitable for industrial applications.

4. Infrared (IR) Sensor: Measures temperature remotely by detecting infrared radiation emitted from objects. This sensor is useful in environments where direct contact is not feasible, such as in the medical or food processing industries.

5. LM35 sensor: This is a type of sensor that generates a voltage signal directly related to temperature, with high accuracy and easy integration into electronic systems.

6. Thermopile sensor: Consists of many thermocouples connected together to measure large temperature differences, creating an output voltage corresponding to the amount of heat absorbed, often used in non-contact temperature measuring devices.

Temperature sensors have many important applications in industry, medicine, electronics, and many other fields. Here are some common applications of temperature sensors:

1. Manufacturing: In factories and production lines, temperature sensors are used to monitor and control the temperature during the production process, thereby ensuring product quality and process safety. For example, in glass or metal manufacturing, precise temperature control is extremely important.
2. HVAC (Heating, Ventilation, and Air Conditioning): Temperature sensors are used to regulate the temperature in buildings and facilities to create a more comfortable living and working environment.
3. Medical and healthcare: Temperature sensors help monitor and control the temperature in medical equipment, such as incubators, incubators, and in the management of biological or drug samples.
4. Consumer electronics: In appliances such as microwave ovens, electric stoves, and water heaters, temperature sensors ensure that these devices operate at the right temperature, increasing efficiency and safety.
5. Home Automation: In smart home systems, temperature sensors help adjust the temperature according to user preferences and habits, thereby saving energy and improving comfort.
6. Scientific research: In laboratories and scientific research, temperature sensors are used to measure and control temperature in precision experiments and research processes.
7. Automobiles and transportation: Temperature sensors are used to monitor and control engine, cooling system, and cabin temperatures, helping to increase vehicle performance and durability.
8. Renewable energy: In solar energy systems, temperature sensors help monitor the performance and energy conversion efficiency of solar panels.

For more details on Temperature Sensors, please visit: What is a temperature sensor? Structure - Principle - Classification - Application

Photoelectric Sensors

1. Cảm biến quang thu phát độc lập (Through-Beam Sensor): Bao gồm thiết bị phát và thiết bị thu ánh sáng đặt đối diện nhau, cảm biến này có khả năng phát hiện vật thể từ xa lên đến 60m, hiệu quả cao và không bị ảnh hưởng bởi màu sắc hay bề mặt của vật thể.

2. Through-Beam Sensor: Consisting of a transmitter and a light receiver placed opposite each other, this sensor can detect objects from a distance of up to 60m, is highly efficient and is not affected by the color or surface of the object.
3. Retro-Reflection Sensor: Combining a transmitter, a light receiver and a reflector, this type of sensor can detect opaque or transparent objects at a distance of up to 15m, is easy to install and saves wiring.
4. Diffuse Reflective Sensor: Used to detect the position of objects on the production line, useful in industrial automation systems such as packaging and product counting.
5. Color Detection Sensor: Detects the color of an object based on pre-programmed settings and settings. This sensor is improved to minimize external light interference, allowing stable color detection.

Learn more about photoelectric sensors at: What is a photoelectric sensor? 3 common types of photoelectric sensors that are indispensable in automation

Pressure sensor

1. Absolute Pressure Sensor: This type of sensor measures absolute pressure relative to zero pressure (complete vacuum). This device measures pressure values ​​that are not affected by atmospheric pressure variations and is often used in applications that require high accuracy such as in atmospheric science or space technology.
2. Relative Pressure Sensor: This sensor measures environmental pressure relative to the surrounding atmospheric pressure. Suitable for applications such as industrial process control, HVAC and medical.
3. Differential Pressure Sensor: Designed to measure the pressure difference between two points. This sensor is often used in HVAC systems, indoor air quality management and industrial processes.
4. Water pressure sensor: Specialized for pressure measurement applications in hydraulic systems, including measuring water levels in tanks or pipes.
5. Pneumatic pressure sensors: Measure pressure in pneumatic systems, useful in manufacturing industries and scientific experiments.
6. Oil pressure sensors: Designed to monitor pressure in oil hydraulic systems, popular in heavy industries such as construction machinery and forklifts.
7. Explosion-proof oil pressure sensors: Measure pressure in potentially explosive environments, often used in applications such as boilers and chemical processing systems.
8. Diaphragm pressure sensors: Specially designed to measure the pressure of hygiene-sensitive liquids such as in the food and pharmaceutical industries.
9. Vacuum pressure sensors: Measure pressure under vacuum conditions, such as in semiconductor manufacturing or precision scientific applications.
10. Bourdon tube pressure sensors: Based on the principle of a Bourdon tube in a spiral or C-shaped shape, this sensor changes under pressure, measuring the pressure of a liquid or gas at a specific time.

If you want to find the right pressure sensor for your needs, refer to the selection guide at:  How to choose pressure sensor

Position sensor

Types of position sensors
Below is a summary of the types of position sensors, classified according to their operating mechanism and measurement method:

1. Potentiometric position sensor: Uses a resistive track with a moving wiper on it, changing the resistance between two points to determine position. This method allows linear position measurement based on changes in resistance.
2. Capacitive position sensor: Works based on changes in the dielectric constant or overlap area between electrodes, allowing distance or movement of an object relative to the electrode.
3. Magnetic position sensor: Measures the distance between a magnet and the sensor by using the interaction between the current pulse and the magnetic field of the magnet, generating acoustic waves or shear waves in the waveguide.
4. Current-based position sensor: Measures the distance of a conductive body by using alternating current to generate eddy currents, thereby generating a secondary magnetic field with the coil impedance effect.
5. Hall effect position sensor: Used to measure the moving position of a part linked to a magnet, thereby generating a Hall voltage corresponding to the position of the magnet.
6. Optical position sensors: Rely on light transmitted and reflected or absorbed by an object to measure changes in properties such as phase, polarization, wavelength, and light intensity.

Position sensors play an essential role in many industries, helping to improve accuracy, efficiency, and safety in manufacturing operations. Here are some common applications of position sensors in different industries:

1. Robotics and automation: Position sensors are used to improve the control and accuracy of robots in automated processes such as assembly, welding, and painting. They help robots determine the exact position of parts and tools quickly and accurately.
2. Machine tools and machining: In the machining industry, position sensors are used to measure the position and movement of machine parts, such as spindles and machine tables, ensuring high precision in product machining.
3. Autonomous vehicle control and positioning: Position sensors play an important role in the control system of autonomous vehicles, helping to determine the position and direction of movement of the vehicle, improving navigation and safety.
4. Medical technology: In the medical field, position sensors are used in diagnostic and surgical equipment, such as in magnetic resonance imaging machines and robotic surgery equipment to ensure the accuracy and repeatability of operations.
5. Factory automation systems: Position sensors help automate manufacturing processes, from material handling to continuous production process control, contributing to increased efficiency and reduced downtime.

Rain water sensor

Rain water sensor is a specialized device to detect water drops, water level, rain, rainfall or water environments. This type of sensor works like a switch. Whenever rain falls on the surface of the sensor plate, the sensor module will read the data from the sensor plate to process and convert it into analog or digital output.

Rain sensor is a special device designed to detect the presence of rain. This sensor is very useful in many fields and has many practical applications as follows:

1. Automotive: In the automotive industry, rain sensors are used to automatically turn on or adjust the speed of the windshield wipers based on the amount of rain falling. This allows the driver to focus on driving without having to worry about adjusting the windshield wipers, thereby increasing safety when driving in bad weather conditions.
2. Home and building automation: Rain sensors are used in home automation systems to automatically close windows and doors when it rains. This helps prevent rainwater from entering the house, ensuring the safety of equipment and furniture.
3. Agriculture: In the agricultural industry, rain sensors can be used to control irrigation systems. When rain is detected, the system can automatically pause operations, helping to save water and prevent over-watering of crops.

See more structure and operating principle: Rain Water Sensor - Structure - Principle - Application

Image sensor

The structure of the image sensor includes the following main parts:

1. Dedicated Light Source: The task of the dedicated light source is to provide the necessary light to ensure that the captured images are always clear, facilitating later image analysis.
2. Lens: The lens has the function of guiding the image to the processing chip, helping to capture images accurately and effectively.
3. Image processing chip (CCD or CMOS): This chip converts the captured optical image into an analog signal, which is the first step in the image processing chain.
4. Analog/Digital Converter: The function of this part is to convert the analog signal received from the image processing chip into a digital signal for easy processing by software.
5. Microprocessors: This is the part that analyzes and processes digital signals, making decisions based on the predetermined parameters of the sensor.
6. Input-Output: Provides communication channels for sensors to connect and control other devices in the system.
7. Peripheral devices: Take on the role of connecting, displaying, controlling and monitoring images intuitively, supporting users in monitoring and operating sensor operations effectively.

Applications of image sensors in industry:

1. Automation industry: Image sensors are widely used in automated machinery such as air compressors and assembly machines, where they help automate manufacturing processes and increase operational efficiency.
2. Pharmaceutical industry: In this industry, image sensors play an important role in checking product quality based on the shape, size, and color of drugs and finished products.
3. Electronics sector: Compact and precise electronic components need to be thoroughly inspected to ensure quality, and image sensors play a crucial role in this, helping to detect manufacturing errors and ensure high accuracy.
4. Packaging industry: Image sensors help ensure that products are packaged correctly and meet quality standards, from checking packaging to positioning products on the production line.
5. Traffic safety: In the field of transportation, image sensors are used to improve road safety, by analyzing images and helping to detect potentially dangerous situations, thereby supporting timely prevention and warning systems.

3. General structure of sensor

1. Protective cover: The outermost part of the sensor, usually made of plastic or metal depending on the usage environment, has the task of protecting the internal components from environmental factors and physical impact.

2. Sensor (probe): This is the main part of the sensor, usually consisting of one or more sensing elements such as sensors or signal transmitters. These elements are capable of detecting and reacting to changes in the surrounding environment, thereby collecting data.

3. Signal converter: It is a part that processes the signals received from the sensor, converting them into standard electrical signals such as 4-20mA, or ON/OFF signals for easy transmission and subsequent processing. This part may include amplifier circuits, stabilizer circuits, and rectifier circuits.

4. Signal processing unit: This is the microprocessor part located in the sensor, which is responsible for analyzing and processing signals from the signal converter, and making necessary decisions or information based on the sensed data.

5. Peripherals: Consisting of components such as rotary transformers and gyroscopes, which convert and stabilize signals, and provide precise information on measured quantities such as rotational angle, speed, and angular deviation.

4. How the sensor works

5. Practical applications of sensors

Sensor applications span a wide range of fields, serving an essential role in both daily life and industrial production. Here are some typical examples:

In the automation industry:

1. Proximity sensors: Detect objects on conveyor belts.
2. Optical sensors: Check product quality on production lines.
3. Temperature sensors: Control temperature in industrial processes such as furnaces.
4. Pressure sensors: Measure pressure in pneumatic and hydraulic systems.

In consumer electronics:

1. Fingerprint and face sensor: Security for mobile devices.
2. Accelerometer sensor: Automatically rotate the phone screen.
3. Proximity sensor: Turn off the screen when the phone is brought to the ear.
4. Light sensor: Adjust the screen brightness according to the environment.

In the medical industry:

1. Heart rate and blood oxygen sensors: Monitor health status through smart wearable devices.
2. Infrared temperature sensors: Measure body temperature without direct contact.
3. Pressure sensors: Monitor blood pressure.
4. Non-invasive blood glucose sensors: Manage blood sugar for people with diabetes.

In the automotive and transportation industry:

1. Ultrasonic sensors: Assist parking and detect obstacles.
2. Radar and LiDAR sensors: Detect the surrounding environment for autonomous vehicles.
3. Accelerometer and gyroscope sensors: Improve driving stability.
4. Road sign recognition sensors: Enhance safety with driving assistance systems.

In agriculture:

1. Soil moisture sensors: Irrigation system automation.
2. Temperature and humidity sensors: Greenhouse climate control.
3. Spectral sensors: Crop quality assessment and pest detection.
4. RFID sensors: Livestock health management and monitoring.

In smart home system:

1. Motion sensor: Automatically turns lights on/off.
2. Magnetic door sensor: Alerts when windows or doors are opened incorrectly.
3. Smoke and gas sensor: Detects fire or gas leaks.
4. Light sensor: Adjusts indoor lighting to match natural light.

 In IoT and smart cities:

1. Smart Traffic Sensors: Traffic Flow Analysis and Traffic Light Adjustment.
2. Water Level Sensors: Water Resource Management and Flood Warning.
3. Energy Sensors: Energy Consumption Monitoring and Optimization.

6. Popular sensor brands on the market

Autonics brand sensors

1. Photoelectric sensors: BY series, BYD series (compact type), BUP series (U-shaped photoelectric sensors), BJX series (detection distance up to 30m), BRQ series (Cylindrical type), BJ series,...
2. Super small photoelectric sensors: BS5 series (9mm groove depth photomicro sensor), BS4 series (with built-in jack), BS3 series, BS5-P series (push button type),...
3. Fiber optic sensors: BFX series (digital LCD fiber optic amplifier), BF5 series (single/dual display type), BFC series,...
4. Displacement sensors: BD series (displacement sensor, sensor head and amplifier), BD-C series (communication converter for laser displacement sensor),..
5. LiDAR (Laser scanner): LSE3 series (4-channel 2D laser scanner), LSE2 series (1-channel 2D laser scanner), LSC series, LSE series,..
6. Ultrasonic sensor: UTR series (cylindrical ultrasonic sensor) can detect and measure various materials and surfaces,..
7. Door sensor: ADS-A series (automatic door sensor), ADS-SE1/2 series (automatic door side sensor)
8. Area sensor: BWM series (independent transceiver type positioning sensor), BWML series (beam type positioning sensor), BWC series (cross-area sensor),...
9. Proximity sensor: PRFD series (cylindrical type magnetic induction proximity sensor), MU series (rectangular type), PRD series (cylindrical type, magnetic induction proximity sensor), PR series (cylindrical type, magnetic induction), PRF series (cylindrical type, full metal body), CR series (cylindrical type, capacitive),...
10. Linear position sensor: LPD series (magnetic induction linear type) can detect the movement and linear position of metal objects,..
11. Pressure sensor: PSS series (compact pressure sensor without indicator), PSAN series (digital display type), PSQ series (dual display digital type), PSM series (multi-channel display),...
12. Temperature sensor: THD series (compact temperature and humidity converter), 7-segment LED display,..

Buy cheap Autonics sensors at: Amazen Industrial Electrical Equipment

1. High Durability: Autonics products are designed to withstand harsh industrial conditions, including dust, heat, and vibration.
2. Accurate and Reliable: Autonics sensors provide accurate measurement results, increasing the efficiency and reliability of automation systems.
3. Easy Integration: Products can be easily integrated into most existing industrial automation systems.

Hanyoung brand sensor

1. Photoelectric sensors: PRA series (round type photoelectric sensors), PEA series, PQ series (compact long-distance photoelectric sensors), PB series, PTX series (integrated power supply), PR series (cylindrical type), PU series (U-type),...
2. Proximity sensors: UP series (square type), UP-25F series, CUP series (capacitive type proximity sensors),..
3. Area sensors: PAS series (thin type area sensors), PAN series (high reliability area sensors with dedicated chips),...
4. Fiber optic sensors: PFB series (bar display fiber optic sensors), FOH series (optical cables), PFD series (multi-function digital fiber optic sensors),..
5. Sensor controllers: HPAN series, HPA-12 series,..

See more details about Hanyoung sensors: https://amazen.com.vn/cam-bien/hanyoung.html

1. ​​​​​​Wide Range of Sensors: Hanyoung offers a wide range of sensors, including proximity sensors, photoelectric sensors, temperature sensors, and pressure sensors, each available in a variety of designs and sizes to suit a variety of needs.
2. Versatile Features: Many Hanyoung sensors are capable of providing multi-function outputs, which can be configured to suit the specific requirements of each application.
3. High Durability: Hanyoung sensors are made from high-quality materials to resist wear and tear over long periods of use, ensuring durability in industrial environments.
4. Suitable for Industrial Environments: These sensors are designed to withstand industrial conditions such as vibration, high temperatures, and exposure to chemicals.

Fotek brand sensor

1. Photoelectric sensors: K3/P3 series (long-distance photoelectric sensors), LCT/LCG series (waterproof Lane photoelectric sensors), PP/PS/EX series, SU series (U-type), M18 series (cylindrical photoelectric sensors),..
2. Proximity sensors: PS series (inductive proximity sensors), PM series (inductive proximity sensors), TW series (two-wire inductive proximity sensors), CP series (capacitive proximity sensors), M12/M18 series (linear proximity sensors),..

Genuine Fotek sensor supplier: Amazen Industrial Electrical Equipment

CONOTEC brand sensor

1. CO2 sensor: FS-600R with the characteristics of transmitting CO2, temperature, humidity, light (RS-485) sensors,..
2. Temperature and humidity sensors: CNT-CS24, CNT-HDC4T, HCPV-220NH
3. Temperature sensor: S-N03-3.3K, S-N03, FS-200N, FS-201,...
4. Humidity sensor: HCPV-220H

For more details about CONOTEC sensor lines, please visit: SENSOR CONOTEC

7. Conclusion