Analysis of wave aberration influence on reducing focal spot size in a high-aperture focusing system
Khonina, S N; Ustinov, A V; Pelevina, E A; Khonina, S N; Image Processing Systems Institute of Russian Academy of Sciences, 151 Molodogvardeiskaya str., Samara 443001, Russia ; Samara State Aerospace University, 34 Moskovskoye shosse, Samara 443086, Russia; Ustinov, A V; Image Processing Systems Institute of Russian Academy of Sciences, 151 Molodogvardeiskaya str., Samara 443001, Russia; Pelevina, E A; Samara State Aerospace University, 34 Moskovskoye shosse, Samara 443086, Russia
Журнал:
Journal of Optics
Дата:
2011-09-01
Аннотация:
It was shown that the presence of wave aberrations (analyzed in the form of Zernike functions) in high-numerical-aperture focusing systems results in narrowing of the transverse dimension of the focal spot below the diffraction limit. Moreover, for linear polarization, the most common for modern lasers, the results achieved along one direction are better than for the radial polarization, the obtaining of which requires complex or expensive devices. Overcoming of the diffraction limit happens due to a substantial reduction of energy in the central part of the focal region. However, the possibility of the registration of light fields that have a very low intensity provides perspectives on the received results. It was also shown that not only the size of the light spot can be reduced, but also the shadow area, formed by a light ring with very small radius.
1.513Мб