Aerosol Spectrometers

Measurement of particle size and particle concentration of aerosols in industrial processes, environment, filter testing, etc.


The success of the Palas® aerosol spectrometers is based on the development of the measurement method with a white light source, 90° scattered-light detections and an optically defined measurement volume by the University of Karlsruhe, KIT.

To the very day it is the world's only optical measurement method that ensures precise particle and concentration determination over a wide measuring range up to 106 particles/cm3 .

2008 the development led to the welas® digital system (White Light Aerosol spectrometer System) with patented T-aperture technology. The patented optical fibre technology allows reliable quasi-simultaneous measurement at two measurement points with one device and in chemically aggressive waste gases.

Palas® offers with the model groups welas® digital, Promo® and Fidas® the most modern, reliable and scientifically most thoroughly investigated optical aerosol spectrometers in the world.

Optical aerosol spectrometers (OAS, ISO 21501-1, VDI 3867-4) and optical particle counters (OPC, ISO 21501-4) show different characteristics. Read more about the substantial difference.

Differences between the aerosol spectrometers

Measurement device:
welas® digital
Possible applications
for very precise particle size and concentration analyses with a high time resolution
for process measurement technology and monitoring applications with continuous measurement
Time resolution
10 ms
1 s
Installed measurement software and analyze software on laptop / PC
for easy handling via internal touchscreen PC
Software / Firmware
PDControl software with many setting and display features, e.g. refractive index
intuitive Promo® firmware for user-friendly operation
for automatic filter testing with Palas® test rigs and the FTControl software
for integration into process control units
external control, e.g. via modbus


Unsere Webseite verwendet Cookies, um Ihnen ein angenehmeres und sicheres Surfen zu ermöglichen.

Cookies sind für die Funktionalität des Benutzerbereichs sowie für die Warenkörbe notwendig.

Um unser Angebot und unsere Webseite weiter zu verbessern, erfassen wir anonymisierte Daten für Statistiken und Analysen.

Contact Directly

Phone: +49 721 96213-0

Contact Form

Buy/Rent/Lease Product

Buy product

Rent or lease product


Subscribe to newsletter