Inside an optical particle counter
Explore an optical particle counter. Follow individual particles through a laser beam, watch photodiode pulses, and compare fine, coarse and mixed aerosols.
Particles. Light. Insight.
Inside an optical particle counter.
Watch individual particles cross a laser beam. See how scattered light
becomes a pulse, a particle count and a size distribution.
Follow a single particle
Every particle leaves a signal.
- < 2.5 µm
- 2.5–10 µm
- ≥ 10 µm
- Sample air
- Sheath air
- Laser
Explore the measurement
AEROSOLMostly small particles. Changes affect incoming particles; reset counts to start a new distribution.
Guide the particles
Sample air carries particles through the nozzle. Filtered sheath air surrounds the sample in the chamber.
Capture the scattered light
Each particle crossing the laser scatters light. A collecting mirror directs part of that light to the photodiode.
Count and classify
The analyser counts pulses and sorts particles into diameter channels. The histogram builds up as particles pass.