Rejilla de defoco (Spanish text).

摘要

This thesis describes the design and manufacture of a non-conventional diffraction grating, referred to as a Defocus Grating. It was designed by adding to the equation of the lines of a standard grating, a function of quadratic phase, which generated a family of off-set concentric circles. The pattern of lines is determined by a parameter of defocus W₂₀, that controls the line's curvature. The grating was made photographically by reducing a printed object onto a 35 mm transparent slide. In combination with a lens, the system maps a single object plane into a series of images, each with a different level of defocus. The images are produced simultaneously in the different diffraction orders. The proper functionality of the grating was confirmed qualitatively. The distances between image planes of first order was measured. The diffraction orders remain spatially separated along the optical axis according to the level of defocus W ₂₀ of the grating. Although symmetry is predicted, little symmetry about the zeroth order was observed.