This paper shows the possibility of the measurement of a temperature field generated by heated fluid from a synthetic jet (SJ) actuator. Examples from field trials of HAPI show images of freshly emitted tree pollen and mineral dust.

The construction of HAPI consists of 3D printed polymer structures that enable a sufficiently low size and weight that it may be flown on a commercial-grade UAV.

The instrument, called the holographic aerosol particle imager (HAPI), has the unique ability to image multiple particles freely entering its sensing volume from any direction via a single measurement. Using digital holography, the instrument obtains the images in a non-contact manner, resolving particles larger than ten micrometers in size in a sensing volume of approximately three cubic centimeters. We describe a new instrument carried by an unmanned aerial vehicle (UAV) that images free-floating aerosol particles in the atmosphere. Improved instrumentation capable of determining the size and shape of aerosol particles is needed in efforts to reduce this uncertainty. The lack of quantitative characterization of aerosol particles and their loading in the atmosphere is one of the greatest uncertainties in climate-change science. These results prove the ability of the proposed technique to analyze planar waveguides having any complicated refractive index profile. The resulting profiles are then fed to the proposed theoretical model and a full TE mode analysis is obtained. Then a phase-shifting digital holographic technique with the help of a Mach–Zehnder-like interferometer, is used to characterize the samples and measure their modified refractive index profiles. Two samples are fabricated from polymethylmethacrylate (PMMA) polymeric material using different parameters for the used UV-laser. The necessary theoretical model is derived and the characterization method given in detail. We propose a general technique based on the WKB approximation and digital holographic interferometry to characterize slab waveguides with arbitrary refractive index profile. In the current paper, we focus on studying the polymeric planar waveguides fabricated by the method of UV–excimer–laser lithography. The fabrication of waveguides with different properties represents an expanding direction in both the industrial and scientific fields. Future optical technologies are basically depending on and employing different types of optical waveguides.

Ghost in the shell hologram tutorial