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We show a system capable of projecting a video scene onto a white-light holographic screen to obtain a kind of image that results in a plane in front of the screen. This holographic screen is mainly a diffractive lens and is constructed by holography. The image plane can be located at any azimuth angle and seen with continuous parallax and without the use of goggles or any special visualization equipment. The image is not volumetric, but when the plane is oblique to the observer its appearance looks very close to a real volumetric image.

In this paper we describe one setup employed for the recording of two types of holographic screens that can be used in white-light applications. We show how to obtain holographic screens with areas up to 1370 cm 2 and diffraction efficiency of 17%. We analyze the holographic screens in their relevant aspects as to focal lengths, theoretical approach, sizes and diffraction efficiencies specifying when each type is appropriate for particular applications.

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Con el surgimiento de los hologramas reconstruibles con luz blanca y su desarrollo posterior, se abrieron grandes posibilidades para su utilización como medio de enseñanza por la característica de producir una imagen tridimensional que constituye un duplicado óptico de un objeto. En el trabajo se describen las características distintivas del holograma como un medio de enseñanza de la física y se analiza su utilización en carreras de ingeniería, mediante la fundamentación, el diseño y construcción de una Exposición Didáctica de Holografía creada para este propósito.

Neste artigo, previamente divulgado em inglês [1], demonstramos que a luz difratada por um simples disco digital pode ser usada para gerar imagens com atributos basicos interessantes. Comparamos esses atributos com os obtidos com elementos refrativos. Um disco digital resulta funcionar como um axicon que gera um feixe se propagando em forma de línea e, porque a posião de focalização da imagem depende do comprimento de onda da luz difratada, logo o elemento pode ser usado como um filtro espectral. Os experimentos são de fácil reprodução, permitindo o entendimento de imagens que os estudantes observam diariamente na escola ou em casa.

Pseudoscopic (inverted depth) images made with spiral diffracting elements intermediated by a pinhole is explained by its symmetry properties. The whole process is made under common white light illumination and allows the projection of images. The analysis of this projection demonstrates that the images of two objects pointing away longitudinally have the main features of standard pseudoscopic image points. An orthoscopic (normal depth) image has also been obtained with the breaking of the symmetry conditions.

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