Self-wavefront interference using transverse splitting holography

Autor: Andrei-ioan Bleahu, Shivasubramanian Gopinath, Tauno Kahro, Soon Hock Ng, Kaupo Kukli, Aile Tamm, Saulius Juodkazis, Joseph Rosen, Vijayakumar Anand
Jazyk: angličtina
Rok vydání: 2023
Předmět:
Zdroj: Results in Physics, Vol 52, Iss , Pp 106839- (2023)
Druh dokumentu: article
ISSN: 2211-3797
DOI: 10.1016/j.rinp.2023.106839
Popis: Manufacturing diffractive lenses with a high Numerical Aperture (NA) is a challenging task due to limitations in lithography methods and the inverse relation between the width and the radius of the zones. With low-resolution lithography techniques such as photolithography, the zone width reaches the lithography limit within a short radius, resulting in low-NA diffractive lenses. With high-resolution electron beam lithography, it is possible to manufacture high-NA diffractive lenses by prolonged writing. However, in this case, the width of the outermost zones becomes subwavelength, inducing undesirable polarization effects. In this proof-of-concept study, a holography solution has been demonstrated to enhance the imaging resolution of low-NA diffractive lenses. The light from an object is partly modulated by the low-NA diffractive lens and interfered with the remaining unmodulated light outside the area of the diffractive lens. This self-interference hologram of the object is processed in the computer with the point spread hologram to reconstruct the object with a resolution corresponding to the NA of the image sensor. This new imaging technique is called Self-Wavefront Interference using Transverse Splitting Holography (SWITSH). A resolution enhancement of ∼10 times has been demonstrated using a low-NA diffractive lens and SWITSH compared to direct imaging with the same low-NA diffractive lens.
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