Sensors shape modern life — from smartphones and wearable gear to factory floors and water-treatment plants — by turning physical signals into actionable data. They help you monitor motion, chemistry, pressure, light and more so decisions can be faster and safer.
There are 35 Examples of Sensors, ranging from Accelerometer to pH Sensor to illustrate that span. Each entry is organized into Category,Measures (unit),Typical applications (max 15 words) so you can quickly compare function, units and common uses — you’ll find below.
How do I choose the right sensor for my project?
Pick a sensor by defining what you need to measure, the required range and accuracy, the environmental conditions (temperature, humidity, exposure), and the interface (analog, I2C, SPI). Check calibration needs, response time and compatibility with your processing hardware; prototyping with a few candidates helps confirm real-world performance.
Can different sensors be combined for more reliable results?
Yes — sensor fusion improves reliability: align sampling rates, synchronize timestamps, and apply filtering or fusion algorithms (e.g., combining accelerometer and gyroscope for orientation). Also account for cross-sensitivity and perform shared calibration (temperature compensation for pH sensors, for example) to ensure consistent, accurate combined readings.
Examples of Sensors
| Name | Category | Measures (unit) | Typical applications (max 15 words) |
|---|---|---|---|
| Accelerometer | MEMS | Acceleration (g, m/s²) | Smartphones (orientation), cars (airbags), gaming controllers, earthquake detection. |
| Gyroscope | MEMS | Angular velocity (°/s) | Drones (stability), smartphones (image stabilization), virtual reality, navigation systems. |
| Pressure Sensor | MEMS | Pressure (Pa, psi, bar) | Weather stations (barometers), cars (tire pressure), medical devices (blood pressure monitors). |
| Strain Gauge | Mechanical | Strain (microstrain, ε) | Weighing scales, structural testing of bridges, aircraft wings, medical instruments. |
| Load Cell | Mechanical | Force (N), Weight (kg, lb) | Digital weighing scales, industrial process control, robotics, material testing. |
| Flow Sensor | Mechanical | Flow rate (L/min, m³/s) | Water meters, gas pumps, HVAC systems, medical ventilators, coffee machines. |
| Microphone | MEMS | Sound pressure (Pa) | Smartphones, voice assistants, hearing aids, audio recording, concert halls. |
| Photodiode | Optical | Light intensity (lux, W/m²) | Remote controls, light meters, smoke detectors, fiber optic communication, medical imaging. |
| LDR (Photoresistor) | Optical | Light intensity (lux) | Automatic streetlights, smartphone screen brightness control, camera light meters, nightlights. |
| Image Sensor | Optical | Light pattern (pixels) | Digital cameras, smartphones, webcams, security cameras, telescopes, medical imaging. |
| Infrared (IR) Sensor | Optical | IR radiation (W/m²) | Remote controls, passive motion detectors, night vision cameras, thermal imaging. |
| Proximity Sensor (Optical) | Optical | Presence (binary), distance (mm) | Smartphone screens (disables touch during calls), automatic faucets, factory automation. |
| Hall Effect Sensor | Electrical | Magnetic field strength (T, G) | Car wheel speed sensors, brushless motor control, compasses, current sensing. |
| Current Sensor | Electrical | Current (A) | Battery chargers, motor controllers, smart plugs, power monitoring systems. |
| Magnetometer | Electrical | Magnetic field (T, G) | Digital compasses in phones, navigation systems, metal detectors, space exploration. |
| Thermocouple | Electrical | Temperature (°C, °F) | Industrial furnaces, ovens, gas engines, water heaters, scientific labs. |
| Thermistor | Electrical | Temperature (°C, °F) | Digital thermometers, refrigerators, 3D printers, car engines, battery packs. |
| RTD (Resistance Temperature Detector) | Electrical | Temperature (°C, °F) | Laboratory measurement, food processing, chemical plants, precision industrial processes. |
| Infrared Thermometer | Optical | Temperature (°C, °F) | Non-contact forehead thermometers, industrial furnaces, food safety checks, electrical inspections. |
| Gas Sensor | Chemical | Gas concentration (ppm) | Carbon monoxide detectors, air quality monitors, breathalyzers, industrial safety systems. |
| pH Sensor | Chemical | Acidity/Alkalinity (pH) | Swimming pools, water quality testing, hydroponics, chemical laboratories, food production. |
| Humidity Sensor | Chemical | Relative humidity (%RH) | Weather stations, HVAC systems, smart home thermostats, humidors, food storage. |
| Ultrasonic Sensor | Mechanical | Distance (cm, m) | Car parking assist, robotics (obstacle avoidance), tank level monitoring, automatic doors. |
| LIDAR | Optical | Distance (m), 3D point cloud | Self-driving cars, robotics, archaeology, atmospheric research, 3D mapping. |
| GPS Receiver | Electrical | Position (latitude, longitude) | Car navigation, smartphones, asset tracking, fitness watches, surveying. |
| Rotary Encoder | Mechanical/Optical | Rotational angle (°), speed (RPM) | Digital volume knobs, robotics, CNC machines, conveyor belts. |
| Linear Encoder | Mechanical/Optical | Position (mm, µm) | 3D printers, CNC machines, inkjet printers, scientific instruments. |
| Heart Rate Sensor | Biosensor/Optical | Heart rate (BPM) | Fitness trackers, smartwatches, medical monitors, exercise equipment. |
| Blood Glucose Monitor | Biosensor | Glucose level (mg/dL) | Personal and clinical diabetes management, continuous glucose monitoring (CGM). |
| Pulse Oximeter | Biosensor/Optical | Blood oxygen saturation (SpO2 %) | Hospitals, clinics, smartwatches, home health monitoring. |
| IMU (Inertial Measurement Unit) | MEMS | Multi-axis motion (g, °/s) | Drones, smartphones, rockets, virtual reality headsets, robotics. |
| Rain Sensor | Optical/Electrical | Presence of water (binary) | Cars (automatic wipers), irrigation systems, weather stations. |
| Tilt Sensor | Mechanical/MEMS | Inclination, tilt angle (°) | Construction equipment, gaming controllers, vehicle alarms, cameras (leveling). |
| Touch Sensor (Capacitive) | Electrical | Touch, proximity (binary) | Smartphone screens, trackpads, smart home appliances, elevator buttons. |
| Flex Sensor | Mechanical | Bend, flex angle (°) | Robotics (joint movement), gaming gloves, medical devices, physical therapy. |
Images and Descriptions
Accelerometer
Measures acceleration forces, including static gravity and dynamic motion. It’s why your phone screen rotates and your fitness tracker counts steps. MEMS versions are tiny chips found everywhere.
Gyroscope
Detects rotation and changes in orientation. It works with an accelerometer to provide a full picture of motion, keeping drones stable and making VR feel immersive and less nauseating.
Pressure Sensor
Measures the force applied by a fluid (liquid or gas) on a surface. These are essential for everything from forecasting weather to ensuring your car’s tires are properly inflated.
Strain Gauge
A very thin foil that changes its electrical resistance when stretched or compressed. It’s the core component in most digital scales and is used to measure stress on structures.
Load Cell
A transducer that converts force into an electrical signal. Most load cells use internal strain gauges to detect the deformation caused by weight, making them key for accurate measurements.
Flow Sensor
Measures the amount of a fluid or gas that passes through it. Different types exist, using principles like turbines, ultrasound, or thermal properties to monitor flow in pipes.
Microphone
Converts sound waves into an electrical voltage signal. Tiny MEMS microphones are in every modern smartphone, enabling calls and voice commands by capturing the physical vibrations of sound.
Photodiode
A semiconductor device that converts light into an electrical current. It’s incredibly fast and sensitive, making it perfect for receiving signals from your TV remote or in high-speed data links.
LDR (Photoresistor)
A simple resistor whose resistance decreases as the amount of light falling on it increases. It’s a low-cost way for devices to know if it’s light or dark outside.
Image Sensor
An array of millions of tiny light-sensitive photodiodes (pixels) that capture the light from a scene to create a digital image. This is the “film” of the digital age.
Infrared (IR) Sensor
Senses light in the infrared spectrum, which is invisible to the human eye. It can be used to detect heat from a person (for security) or receive signals from a remote.
Proximity Sensor (Optical)
Often uses an infrared LED and a light detector to determine when an object is near. It’s why your phone screen turns off when you hold it to your ear during a call.
Hall Effect Sensor
Produces a voltage in response to a magnetic field. It’s a versatile, durable sensor used to detect position, speed, and current without any physical contact, making it ideal for harsh environments.
Current Sensor
Measures the flow of electric current in a wire. It can do this by measuring the magnetic field around the wire or by measuring the voltage drop across a precision shunt resistor.
Magnetometer
Measures the strength and direction of magnetic fields, including Earth’s magnetic field. This is how your phone’s map app knows which way is north and helps with navigation.
Thermocouple
Made of two different metals joined at one end. This junction produces a tiny voltage that varies with temperature. They are very rugged and can measure extremely high temperatures.
Thermistor
A resistor whose resistance changes significantly and predictably with temperature. They are inexpensive, highly sensitive, and common in everyday appliances for precise temperature control.
RTD (Resistance Temperature Detector)
A highly accurate and stable temperature sensor. It works by measuring the change in electrical resistance of a pure metal, typically platinum, as its temperature changes over a wide range.
Infrared Thermometer
Measures temperature by detecting the thermal radiation an object emits, allowing for non-contact measurements. Perfect for checking the temperature of moving, very hot, or hard-to-reach objects.
Gas Sensor
Detects the presence and concentration of various gases in the air. Different types use chemical reactions or changes in conductivity to identify specific gases like CO, methane, or alcohol.
pH Sensor
An electrode that measures the hydrogen-ion activity in a water-based solution, producing a small voltage to indicate its acidity or alkalinity on the 0-14 pH scale.
Humidity Sensor
Measures the amount of water vapor in the air. Most modern sensors use a material that changes its capacitance or resistance based on how much moisture it absorbs from the environment.
Ultrasonic Sensor
Works like a bat’s sonar. It emits a high-frequency sound pulse and measures the time it takes for the echo to return, calculating distance based on the speed of sound.
LIDAR
Measures distance by illuminating a target with a pulsed laser and analyzing the reflected light. It can rapidly scan an environment to create a detailed 3D map or “point cloud.”
GPS Receiver
A receiver that triangulates its position by receiving and timing signals from a constellation of satellites orbiting Earth. It’s a sensor system that provides location and time information anywhere on Earth.
Rotary Encoder
A device that converts the angular position or motion of a shaft into a digital signal. It allows a system to precisely track how much something has turned and in which direction.
Linear Encoder
Similar to a rotary encoder but for straight-line motion. It provides precise feedback on the position of a moving part, enabling highly accurate control in automated systems like printers.
Heart Rate Sensor
Often uses photoplethysmography (PPG), shining a green light into the skin and measuring changes in light absorption caused by blood pulsing through capillaries to determine your heart rate.
Blood Glucose Monitor
An electrochemical sensor that measures the concentration of glucose in a blood sample. A chemical reaction on a test strip generates a small electrical current proportional to the glucose level.
Pulse Oximeter
Clips onto a fingertip and uses red and infrared light to measure the oxygen level in your blood by analyzing how differently oxygenated and deoxygenated hemoglobin absorb the light.
IMU (Inertial Measurement Unit)
A single chip that combines an accelerometer and gyroscope (and often a magnetometer) to provide a complete picture of an object’s velocity, orientation, and gravitational forces in 3D space.
Rain Sensor
Detects rainfall. Car sensors often use infrared light reflected off the windshield; when water droplets are present, they scatter the light, triggering the wipers to activate automatically.
Tilt Sensor
Detects the tilting of an object past a certain angle. Simple versions use a metal ball that closes a circuit, while MEMS versions are solid-state and more accurate.
Touch Sensor (Capacitive)
Detects touch by measuring a change in capacitance. Your body is conductive, so when you touch the sensor, you alter its local electrostatic field, which the device registers as a touch input.
Flex Sensor
A simple sensor that changes its electrical resistance when it is bent. This allows for measuring how much a joint is flexing, making it useful for virtual reality gloves or physical therapy.
