Passive scintillometer: theory and field measurements

We propose design of a low-cost passive scintillometer that measures the strength optical turbulence by analyzing scintillation in image straight edge between two areas uniform, but distinct brightness. Two theoretical approaches to scintillations description are developed based on phase screen and rigorous path integral propagation imaging models. Asymptotic analysis both models leads four distinctive situations. uniform approximations cover most promising conclusion for applications. Both width area where exist can be used estimate strength. present results proof-of-concept experiment images specifically made target were taken consumer grade camera equipped with telephoto lens. describe processing separates characteristics from scintillations. The spatial profiles variances at three spectral bands several apertures calculated. As was expected, concentrated around sharp absent uniformly bright parts target. Observed within limits, provide reasonable estimates structure constant across bands. However, dependence aperture inconsistent thin lens theory larger apertures. attribute this Additional bench tests bar targets revealed resolution well below nominal diffraction limit, different setup should order exploit distribution fluctuations.