Achromatic imaging by means of the refractive light sword optical element

Assessment of imaging with extended depth-of-field by means of the light sword lens in terms of visual acuity scale

“…According to previously reported theoretical studies, numerical simulations, and qualitative experiments [12][13][14][15][16][17][18], an element of this kind can form recognizable images of acceptable quality in the presence of a defocus of 0-4 diopters. The LSL demonstrated its superiority over other solutions designed especially for multifocal and EDF imaging.…”

“…In general, they can be divided into three main families: accommodative proposals, multifocal proposals, and proposals with Extended Depth of Field (EDF). Between the members of the second group, there can be found bifocal or multifocal lenses [1,2], whereas in the last group one can find rotationally symmetric phase masks [3][4][5], axicons [6][7][8], lenses with negative spherical aberration [9,10], and light sword optical elements (LSOEs) [11][12][13]. In contrast to other elements, the LSOEs are distinguished by angular variation of the optical power.…”

“…Therefore, fabrication of the LSL represents serious problems and demands. As a result, up to now only two promising, qualitative experiments with LSLs have been presented [13,18]. Such refractive elements were fabricated by the non-uniform exposure of photoresist, but they nevertheless demonstrated distinct aberrations.…”