부산대학교 도서관

Ophthalmology is entering a very interesting period with new diffractive multifocals, improved refractive multifocals, and accommodative lenses, all coming out at the same time. A new diffractive-refractive design for providing intermediated vision is apodization. In an apodized pattern, physical diffractive step heights are reduced in height, in an almost continuously varying manner. This study is aimed to investigate the use of ultrashort laser pulses to ablate the surface of intraocular lenses, and thus provide an alternative to conventional techniques. Ablation experiments were performed on hydrophilic and hydrophobic intraocular lenses (IOLs). The samples were irradiated with a Ti:Sapphire laser at λ=0.785 μm, pulse duration 150 fs, repetition rate 1 kHz and with a Nd:YAG 4ω laser at λ= 0.266 μm, pulse duration 155 ps, repetition rate 10 Hz. We investigated the ablation efficiency and the surface modification with a Scanning Electron Microscope (SEM). The experimental results and the theoretical assumptions on the relevant ablation mechanism are discussed. [ABSTRACT FROM AUTHOR]