Laboratory simulation of atmospheric laser scintillation has been accomplished through a Reflective Membrane Optical Scintillator (RMOS). RMOS incorporates a novel vibrating membrane design that is virtually wavelength independent and statistically programmable in real time. The device has application in the context of wavefront simulation as it exists in turbulent medium. Wavefront disturbances are created by reflecting collimated light off of the membrane surface. The reflected light undergoes spatial modulation and angular redistributions which mimic the effects observed over long path propagation through the atmosphere. Acoustic energy, coupled into the membrane through an electro-mechanical transducer, sets-up nodal vibrational modes in the bounded membrane, creating angular distortion areas that redistribute energy in the reflected beam. The statistics of the energy redistribution is a function of the applied acoustical spectrum, rms transducer voltage, and distance from the membrane surface, as well as the shape and acoustic impedance of the membrane boundary. Laboratory testing of a prototype device indicate spatial irradiance variations in the reflected beam exhibit probability distributions having log-normal symmetry with angle-of-arrival deviations up to 25 milliradians and variances from .01 to 1.0.
Jack H. Parker,
Mark L. DeLong,
"Reflective Membrane Scintillation For Laser Receiver Diagnostics", Proc. SPIE 0999, Laser Radar III, (18 February 1989); doi: 10.1117/12.960242; https://doi.org/10.1117/12.960242