Glossary · Machine vision
Line-scan camera
Also known as: Line camera, Linescan camera
German: Zeilenkamera
In machine vision, a line-scan camera is a camera whose sensor has one or a few rows of pixels; it captures one line per exposure and builds a two-dimensional image from successive lines as the object moves past, synchronized by an encoder or clock.
- Machine vision
In one sentence
A line-scan camera captures one pixel line at a time and builds an image as the object moves, ideal for webs and continuous surfaces.
Example
A line-scan camera above the steel strip inspects the full 1,500 mm width for surface defects at a strip speed of 5 m/s.
How it applies
- Engineering: Line-scan cameras suit continuous material (paper, foil, steel, textiles), very wide objects and cylindrical parts that rotate under the camera. Line rate must match object speed, otherwise the image is stretched or compressed.
- Commissioning: An Encoder on the conveyor or roll triggers lines so that pixel size along the motion direction stays constant when speed changes. Uniform line lighting is required.
- Documentation: The documentation team should document line rate, encoder resolution and scaling, lighting setup and the speed range for which the inspection is validated.
Line-scan camera vs. area-scan camera
An Area-scan camera takes a complete image in one exposure and is easier to set up. A line-scan camera gives very high resolution across wide or endless objects but needs precisely controlled motion.