What Is a Linear Sensor?
A linear sensor, also known as a position sensor, measures linear displacement. These sensors come in various forms including laser sensors, wire encoders, linear encoders, and more, differentiated by their measurement principles such as laser displacement, eddy current, and electromagnetic induction.
Applications of Linear Sensors
Linear sensors are utilized across diverse sectors such as semiconductor and LCD production, electrical machinery, home appliances, the automotive industry, construction machinery, automated warehouses, and the fields of medicine, food processing, and packaging. They play critical roles in:
1. Semiconductor and LCD Manufacturing Equipment
Encoders and camera-based sensors in these industries detect the position of drive stages.
2. Food Manufacturing Plants
Encoders monitor processed food quantities and the height of molded products.
3. Construction Machinery and Automated Warehouses
These sensors provide precise positioning capabilities.
4. Medicine and Other Fields
They measure the opening degree in drainage facilities and ensure accurate positioning for medical equipment like CT scanners and operating tables.
Principle of Linear Sensors
Linear sensors operate on various principles, categorized mainly into non-contact and contact measurements:
1. Non-Contact Displacement Measurement
These include magnetostrictive sensors, laser sensors, linear encoders, and camera-based sensors, each utilizing different technologies to measure displacement without physical contact.
2. Contact-Type Displacement Measurement
Contact-type sensors like linear potentiometers and wire encoders directly measure displacement through mechanical contact.
Features of Linear Sensors
Linear sensors are distinguished by their operational type and specific features:
1. Non-Contact Type Linear Position Sensor
These sensors offer longevity, high accuracy, and speed due to the absence of mechanical wear.
2. Contact-Type Linear Position Sensor
While cost-effective, the mechanical contact leads to shorter lifespans due to brush wear.
3. Laser Sensor
Laser sensors provide high-speed, precise measurements in a compact form, though they struggle with reflective or transparent objects and environmental interference.
4. Wire Encoder
Wire encoders are durable against environmental factors but require maintenance when the wire wears out.
5. Linear Encoder
Offering high precision and speed, optical linear encoders can be affected by dirt and other contaminants.