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Liquid Crystal Displays consist of a regular weave of pixels, each of them made up by three sub-pixels corresponding to Blue, Green and Red colors. In this work a simple experiment showing the internal structure of a common display is performed. Simply putting an amplitude grating on a display, a Moiré pattern is formed. When the lines of the grating are placed along the vertical direction, the fringes show a colorful shape, whereas when the lines are horizontal the fringes show a black and white modulation. An explanation based on the internal structure of the display is given, resulting in a simple and interesting experiment for docent and divulgation activities. [ABSTRACT FROM AUTHOR]

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Bamboo is considered an important raw material in developing countries because its physical characteristics associate lightness with high mechanical resistance. However its behavior obtained from mechanical tests is not yet well defined. This research work had the objective of evaluating bamboo (Guadua angustifolia) testing specimens under simple uniaxial compression loading. Shadow moiré optical methods had been employed to generate deformation mapping as function of knots (0, 1 or 2). Obtained results indicate that the technique is well adequate in generating iso-deformation contour lines in bamboo specimens. [ABSTRACT FROM AUTHOR]

The equilateral hyperbolic zone plates (EHZP) of fixed and variable focal length, who exhibit cross focal shaped pattern, are elements used in far distance transversal detection systems, among others. Nevertheless, the shape that can be achieve with this diffractive systems, is affected by the out of focus produced when data is taken from planes at distances different to the focal distance, In this work we study how the focal pattern of a fixed focal length EHZP varies and how the precision in the measure of the displacement is affected, in planes close to the focal length of the EHPZ. With this we pretend to determine the out of focus sensibility of this elements. [ABSTRACT FROM AUTHOR]