Abstract

Flat lenses with focal length tunability can enable the development of highly integrated imaging systems. This work explores machine learning to inverse design a multifocal multilevel diffractive lens (MMDL) by wavelength multiplexing. The MMDL output is multiplexed in three color channels, red (650 nm), green (550 nm), and blue (450 nm), to achieve varied focal lengths of 4 mm, 20 mm, and 40 mm at these three color channels, respectively. The focal lengths of the MMDL scale significantly with the wavelength in contrast to conventional diffractive lenses. The MMDL consists of concentric rings with equal widths and varied heights. The machine learning method is utilized to optimize the height of each concentric ring to obtain the desired phase distribution so as to achieve varied focal lengths multiplexed by wavelengths. The designed MMDL is fabricated through a direct-write laser lithography system with gray-scale exposure. The demonstrated singlet lens is miniature and polarization insensitive, and thus can potentially be applied in integrated optical imaging systems to achieve zooming functions.

© 2023 Optica Publishing Group

Multilevel diffractive lens in the MWIR with extended depth-of-focus and wide field-of-view

Tina M. Hayward, Syed N. Qadri, Nicole Brimhall, Freddie Santiago, Marc Christophersen, Christopher Dunay, Richard L. Espinola, Hector Martin, C. C. (Teddy) Cheung, and Rajesh Menon
Opt. Express 31(10) 15384-15391 (2023)

Multifocal diffractive lens design in ophthalmology

Aizhong Zhang
Appl. Opt. 59(31) 9807-9823 (2020)

Multifocal diffractive lens generating several fixed foci at different design wavelengths

Leonid L. Doskolovich, Evgeni A. Bezus, Andrey A. Morozov, Vladimir Osipov, James S. Wolffsohn, and Boris Chichkov
Opt. Express 26(4) 4698-4709 (2018)

Diffractive multifocal intraocular lens image quality

Michael J. Simpson
Appl. Opt. 31(19) 3621-3626 (1992)

Machine learning enables the design of a bidirectional focusing diffractive lens

Wei Jia, Dajun Lin, Rajesh Menon, and Berardi Sensale-Rodriguez
Opt. Lett. 48(9) 2425-2428 (2023)