I designed and made an optical Aethalometer to measure the soot particles in the urban atmosphere.
The device works based on the optical transmittance measurement of a glass fiber filter that is loaded with soot particles.
The device was required to work constantly with no need for service over one-month intervals.
A. F. Forughi, M. S. Saidi, Automated system for cumulative measurement of PM10 particles using laser light, Iran Intellectual Property Office, 77372, 2012.