LITHOGRAPH COMPRISING A MOVING CYLINDRICAL LENS SYSTEM

摘要

The invention relates to a lithograph for producing computer-generated holograms in a storage medium (13), provided with a source for generating a write beam (2), a moving lens (4) for focussing the write beam (2), means for displacing the moving lens (4) along a direction of movement (6), and with a means for displacing the write beam (2) in relation to the storage medium (13) in a manner that is perpendicular to the direction of movement (6). The aim of the invention is to provide a lithograph in which disruptions in the movement of a lens perpendicular to the direction of movement thereof do not effect the quality of the hologram. To this end, the moving lens (4) has refractive power only essentially in a first direction that is parallel to the direction of movement (6). In addition, a stationary lens (9) is provided, and this stationary lens (9) has refractive power only essentially in a second direction (5), whereby the second direction (5) is perpendicular to the first direction and to the write beam (2).