Abstract
An artificial screen has been constructed to encode spatial information of simple transparent objects. The constructed encoder is composed of a matrix of small strips, photographed several times on a high resolution film to obtain strips of nearly ten times the average grain size of natural speckles. A second encoder has been constructed by recording a natural speckle pattern on a photographic plate which has gone through a continuous shift during the time of exposure in a specific direction, forming an elongated speckle pattern. A comparison between the results obtained using the two encoders has been presented.