Linear zone plates with a minimum linewidth of 0.69 µm are fabricated by electron-beam writing and deep UV lithographic techniques. The focusing characteristics are examined for laser beams at 0.633 and 0.86 µm in wavelength. A focal length of 200 µm, minimum spot size of 1.0 µm, and a numerical aperture of 0.42 are obtained at λ = 0.633 µm. Possible applications of the present technology to the fabrication of miniaturized focusing elements for opto-electronics are discussed.
© 1984 Optical Society of America
K. Kodate, H. Takenaka, and T. Kamiya, "Fabrication of high numerical aperture zone plates using deep ultraviolet lithography," Appl. Opt. 23, 504-507 (1984)