Backscatter Measurement for Integrating Nephelometers

Ecotech (Australia) is pleased to announce that backscatter measurements are now supplied standard for their Aurora 3000 Integrating Nephelometer.

The Aurora Nephelometers are a series of instruments used for measuring the scattering of light (scattering coefficient) of aerosols in the atmosphere; this information is useful for determining the influence of atmospheric aerosols on the global radiation balance, its impact on global dimming and climate change. The backscatter feature of the Aurora 3000 nephelometer is achieved through the use of a backscatter shutter mounted on the light source housing inside the cell. This shutter moves between two locations in and out of the optical path of the light source (90° to 180°) within the light sources Lambertian distribution. The position of the backscatter shutter is controlled to within ±0.09°, and can be adjusted to achieve other cutoff angles if required for more advanced analysis of backscatter.

The ability to remove and measure the entire light source including the backscatter with the one module has been applauded by a number of customers using the instruments for research applications.

According to Grant Kassell, Ecotech’s R&D Manager: “The backscatter feature is something that we have spent almost as long designing and testing as the new opal glass LED light source that we released in late 2008. Customers who have seen our 3 wavelength backscatter functionality are excited about this improvement to our nephelometer and the valuable data it can now provide. Our customers have also been very interested in the instruments ability to control the angle of the shutter as this may provide additional information that has previously only been available from polar nephelometers.”

Ecotech released their opal glass light source in November 2008. This light source utilizes an opal glass diffuser fitted in front of high intensity LEDs to create a stable, repeatable lambertian distribution. Ecotech offers several different configurations of integrating nephelometers including a single wavelength, multiple wavelength and a PM2.5 correlating version for use in air quality monitoring networks.

Ecotech will be exhibiting their Aurora Integrating Nephelometer at the upcoming International Aerosol Conference to be held in Helsinki in August 2010.