PLANAR PHOTONIC-CRYSTAL MICROLENS Russian patent published in 2013 - IPC H01P3/20 

FIELD: physics.

SUBSTANCE: planar photonic-crystal microlens, having a rectangular entrance aperture, has openings with period d across and along the optical axis in the material of the lens. Even rows of the openings perpendicular to the optical axis of the lens are shifted by d/2 in the positive direction of the transverse axis x. One opening is added to each row on the side of the negative part of the axis x in order to maintain axial symmetry of the openings. The radius of the openings is determined by the relationship where is the average refraction index in a cell with diagonal coordinates (x_a, y_b) and (x_a+1, y_b+1), x_a+1x_a=d, y_a+1-y_a=d, where x is the coordinate which lies transverse to the optical axis, L is the length of the lens, n₀ is the refraction index of the material of the lens.

EFFECT: focusing a plane light wave near its boundary with a small focal spot.

6 dwg