The Open Imaging Nephelometer system is a polarized polar nephelometer to measure scattering as a function of the scattering angle for aerosol and cloud particles in open air. The main characteristic of the Open I-Neph is the fact that it does not require a chamber for the scattering measurements. The Open I-Neph can be used for ground based or aircraft applications and has been integrated, certified and flown in the NASA P3 aircraft.
The left figure shows the 3D model of the Open I-Neph system mounted on the wing of the NASA P3 aircraft while the wright hand figure shows actual photographs of the system right before taking off from NASA Wallops.
This figure shows an actual measurement of the scattering phase function of cloud droplets performed during one of the NASA P3 flight during the DISCOVER AQ experiment.