Tunable Gaussian mask for extending the depth of field

Jorge Ojeda-Castaneda, Emmanuel Yépez-Vidal, Eloy García-Almanza, Cristina M. Gómez-Sarabia

Abstract


We present the use of two asymmetrical amplitude masks, for generating a tunable Gaussian filter. The two masks work as a pair. By introducing a lateral displacement, between the members of the pair, one can tune the width of the Gaussian filter. This tunable mask is useful for controlling unwanted oscillations in the MTFs, which are associated to the use of phase filters extending the depth of field.

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Photonics Letters of Poland - A Publication of the Photonics Society of Poland
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ISSN: 2080-2242