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In this study, we investigated lipid deposition and diffusion in silicone hydrogel (Si-Hy) contact lenses using confocal microscopy. Different Si-Hy lenses were analyzed to understand the interaction patterns of cholesterol with various lens materials. The results highlight significant differences in the deposition and diffusion of lipids through the lenses, revealing that some materials, such as comfilcon A, allow lipids to diffuse more freely compared to others, such as samfilcon A, which provides a greater barrier. The study also observed different morphology and movement of lipid agglomerates across the lenses and above it surfaces. These findings contribute to the understanding of lipid–lens interaction, which is important for the development of lenses with improved comfort and functionality. The research highlights the importance of considering lipid interactions in the design and selection of Si-Hy contact lenses to enhance wearer comfort and lens performance.

In this work a photonic crystal fiber made of a heavy metal oxide glass with optimized dispersion profile is proposed for supercontinuum generation in a broad range of wavelengths in the near-infrared, when pumped by a mode-locked fiber-based laser. The fiber is modelled and optimal geometrical parameters are selected to achieve flat and low dispersion in the anomalous regime. Supercontinuum generation in the range of 0.76⁻2.40 µm, within the dynamics of 30 dB, when pumped at 1.56 µm with 400 fs⁻long pulses and an average power 660 mW is possible. The applicability of such fibers is also discussed.

A photonic crystal fiber made of fused silica glass and infiltrated with nitrobenzene (C6H5NO2) was proposed as a new nonlinear medium for supercontinuum generation (SG). The guiding properties of the fiber structure were studied numerically, including estimation of the effective refractive index, attenuation, and dispersion of the fundamental mode. Based on the obtained results, three optimized structures were selected and tested numerically for SG. With numerical simulations of nonlinear propagation, we demonstrated the feasibility of spectrally broad and coherent SG in the proposed structures. For the first we obtained a supercontinuum (SC) in the range of 0.8–1.8 µm, for the second in the range of 0.8–2.1 µm, and for the third 1.3–2.3 µm. The pulse energy was in the range of 0.06–0.5 nJ while the pulse duration was 90 fs or 120 fs. For all structures an SC was formed in the first centimeter of the light propagation and conveniently allowed to assume short segments of the fibers. The proposed fibers are good candidates for all-fiber SC sources constituting an attractive alternative to glass-core fibers, since the nonlinearity of nitrobenzene is significantly higher than that of silica. The proposed solution may lead to new low-cost all-fiber optical systems for SG. [ABSTRACT FROM AUTHOR]

A photonic crystal fiber made of fused silica glass, infiltrated with chloroform (CHCl3), is proposed as a new source of supercontinuum (SC) light. Guiding properties in terms of effective refractive index, attenuation, and dispersion of the fundamental mode are studied numerically. As a result, two optimized structures are selected for and verified against SC generation in detail. The dispersion characteristic of the first structure is all-normal and equals  −7 ps  ·  nm−1 · km−1 at 0.92 μm, while the dispersion characteristic of the second structure has the zero-dispersion wavelength at 1 μm, and SC generation was demonstrated for the wavelength 1.03 μm. We prove the possibility of coherent octave-wide SC generation in the wavelength range of 600–1260 nm and soliton fission based low-coherence flat SC in the wavelength range of 600–1400 nm, with 400 fs pulses and 0.8 nJ of energy in-coupled into the core of the studied structures. Proposed fibers are good candidates for all-fiber SC sources as an alternative to glass core fibers, since nonlinearity of CHCl3 is higher than silica and its toxicity is negligible. The proposed solution may lead to new low-cost all-fiber optical systems. [ABSTRACT FROM AUTHOR]