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An aircraft cabin is used as a laboratory for studying the atmospheric pressure during a flight. All the different steps of the flight: take-off, cruise altitude climbing and landing are monitored with the use of the pressure sensor of a smartphone. Specific details of the atmospheric pressure during take-off and landing are given. Calculations are done for the aircraft nose elevation angle during take-off, with the relation between the optimized cabin pressure for the passenger comfort and the aircraft altitude.

Thin films of inorganic materials as Tin-doped indium oxide, titanium oxide, Niobium doped titanium oxide, were deposited for comparison on glass and Polyethylene terephthalate (PET) substrates with a DC sputtering method. These thin films have been characterized by different techniques: Dektak Surface Profilometer, X-ray diffraction (XRD), SEM, (UV/Vis/NIR) spectrophotometer and spectroscopic ellipsometry (SE). The optical parameters of these films such as transmittance, reflectance, refractive index, extinction coefficient, energy gap obtained with different electronic transitions, real and imaginary ({\epsilon}_r,{\epsilon}_i) dielectric constants, were determined in the wavelengths range of (200 - 2200) nm. The results were compared with SE measurements in the ranges of (0.56- 6.19) eV by a new amorphous model with steps of 1 nm. SE measurements of optical constant have been examined and confirm the accuracy of the (UV/Vis/NIR) results. The optical properties indicate an excellent transmittance in the visible range of (400 - 800) nm. The average transmittance of films on glass is about (86%, 91%, 85%) for (ITO, TiO2, TiO2:Nb (NTO)) respectively and decreases to about (85%, 81%, 82%) for PET substrates. For all these materials the optical band gap for direct transition was (3.53, 3.3, 3.6) eV on glass substrates and on PET substrates using two methods (UV and SE). A comparison between optical constants and thickness of these ultrathin films observed gives an excellent agreement with the UV results. The deposited films were also analyzed by XRD and showed an amorphous structure. The structural morphology of these thin films has been investigated and compared., Comment: 42 pages, 12 figures

In the present work, ultrathin films of Zinc oxide (ZnO) and Aluminum doped zinc oxide (AZO) with 20 nm thick were fabricated at 300 K on glass and Polyethylene terephthalate (PET) substrates by means of directcurrent sputtering method. The structural morphology of the films were analyzed by (XRD) diffractometry. The average transmittance of films deposited on different substrates showed high transparency (over 80%) in the visible spectrum. The objective of the present work is to investigate the thicknesses and optical constants of ZnO and AZO ultrathin films prepared by DC sputtering onto (glass and PET) substrates using two methods (UV-vis-NIR spectrophotometer and ellipsometer (SE) by new amorphous dispersion formula) with comparison to check and confirm the results that obtained from UV with those obtained from SE measurements. The optical constants of films were extracted and compared using UV and SE techniques in the range of (200- 2200 nm) with increment of 1 nm in order to confirm the accuracy of the UV and shown an excellent agreement., Comment: 24 pages, 6 figures, 6 tables

We demonstrate that linear absorption coefficient (LAC) of a graphene-silicon hybrid waveguide (GSHW) is determined by the optical transmission spectra of a graphene coated symmetrically coupled add-drop silicon microring resonator (SC-ADSMR), of which the value is around 0.23 dB/um. In contrast to the traditional cut-back method, the measured results are not dependent on the coupling efficiency of the fiber tip and the waveguide. Moreover, precision evaluation of graphene coated silicon microring resonator (SMR) is crucial for the optoelectronic devices targeting for compact footprint and low power consumption., Comment: 7 pages, 6 figures, published in Optics Express (2016)

We have previously shown that azopolymer thin films exposed to coherent light that has travelled through a turbulent medium produces a surface relief grating containing information about the intensity of the turbulence; for instance, a relation between the refractive index structure constant C2 as a function of the surface parameters was obtained. In this work, we show that these films capture much more information about the turbulence dynamics. Multifractal detrended fluctuation and fractal dimension analysis from images of the surface roughness produced by the light on the azopolymer reveals scaling properties related to those of the optical turbulence., Comment: 8 pages, 5 figures

We present an optical experiment which permits to evaluate the information exchange necessary to self-induce cooperatively a well-organized pattern in a randomly activated molecular assembly. A low-power coherent beam carrying polarization and wavelength information is used to organize a surface relief grating on a photochromic polymer thin film which is photo-activated by a powerful incoherent beam. We demonstrate experimentally that less than 1% of the molecules possessing information cooperatively transmit it to the entire photo-activated polymer film., Comment: 16 pages, 4 figures