METHOD FOR DIRECT LASER WRITING OF KINOFORM LENSES IN THICK LAYERS OF PHOTORESIST-TYPE PHOTOSENSITIVE MATERIALS (VERSIONS) Russian patent published in 2013 - IPC G02B3/08 G02B1/12 

FIELD: physics.

SUBSTANCE: laser radiation focused on the surface of a photosensitive layer is modified on depth in proportion to the power density of the radiation propagating in the photosensitive layer. Before entering a focusing lens, the laser radiation is collimated into a parallel beam whose diameter is smaller than the entrance aperture of said lens and is shifted in parallel to the optical axis by a value where one of the edges of the longitudinal section of the exposing radiation cone in the photoresist layer becomes parallel to the optical axis of the focusing lens. In the second version, an immersion liquid is further placed in the interval between the output lens of the focusing lens and the surface of the photosensitive layer.

EFFECT: high diffraction efficiency of kinoform lenses by reducing loss on counter slopes of zones by increasing the gradient of the slopes formed directly during direct laser writing.

2 cl, 4 dwg, 1 tbl