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Large-core polymer optical fiber (POF) links have limitations in capacity and reach due to the fibers' high modal dispersion and attenuation. Most of these links use red laser diodes, even though the attenuation spectrum of poly(methyl methacrylate) (PMMA), the basic polymer used to manufacture these fibers, has a lower minimum in the green region. Therefore, we set out to explore the potential use of green light in transmission systems, comparing the performances of three step-index polymer optical fibers (SI-POFs) with different numerical apertures. We obtained measurements of intensity distribution, frequency response and bit error rate (BER), as functions of fiber length. We have also compared the fibers' frequency responses with red and green light for a few selected lengths. Our results confirm that SI-POFs attenuate less in response to green light, which can increase their length. This advantage is partially counterbalanced by a slightly higher dispersion that limits the capacity of the high-aperture fibers, particularly at relatively short lengths. Our conclusions are critical to understanding SI-POF behavior and to designing thorough SI-POF models that can aid the design of POF-based links for different scenarios.
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http://dx.doi.org/10.3390/polym13193397 | DOI Listing |
Inorg Chem
September 2025
Departmento de Química Inorgánica, Universidad de Valencia, C/Dr. Moliner 50, 46100 Burjasot, Valencia, Spain.
[Cu(3-bph)(PABA)(HO)] () (3-bph = ,'-bis(3-pyridylmethylene)hydrazine and PABA = -amino benzoate) is a pyridyl-N bridging Cu coordination polymer, and PABA acts as a carboxylate-O donor forming a square pyramidal CuNO motif following a zigzag one-dimensional (1D) lattice. The shows weak antiferromagnetic coupling ( = -0.196(1) cm), and emission appears at 352 nm (λ = 293 nm), which is selectively quenched by Fe via the FRET mechanism.
View Article and Find Full Text PDFJ Refract Surg
September 2025
Department of Refractive Surgery, Shanghai Aier Eye Hospital, Shanghai.
Purpose: To analyze the effects of ablation interruption on ablation depths and clinical refractive outcomes to characterize the impact of ambient temperature changes and ablation interruption on ocular surface temperature (OST) during excimer laser ablation.
Methods: This prospective study was conducted on laser ablations in polymethylmethacrylate (PMMA) plates and porcine corneas to simulate laser in situ keratomileusis (LASIK) treatments using the EX500 laser (Alcon Laboratories, Inc) at ambient temperatures of 18, 20, and 22 °C. Ablation interruption was performed for 1, 2, 3, 4, and 5 seconds at the 10th second of the treatment of -9.
J Refract Surg
September 2025
From the Department of Ophthalmology at University of São Paulo, São Paulo, Brazil.
Purpose: To analyze stabilization results using various standard and accelerated corneal cross-linking (CXL) protocols in patients younger than 18 years.
Methods: This systematic review was conducted in accordance with the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) 2020 guidelines. A bibliographic search was carried out based on PubMed and Scopus data, with the last being performed in December 2024.
J Refract Surg
September 2025
Purpose: To evaluate tilt, decentration, and axial stability of the Clareon toric intraocular lens (TIOL) (CNW0T3-9; Alcon Laboratories, Inc) over a 6-month follow-up period.
Methods: A single-center, prospective, interventional clinical trial was conducted with a study population of 130 eyes from 82 patients who received a Clareon TIOL. Tilt, decentration, and the aqueous depth were determined preoperatively and at 1 week and 6 months postoperatively using anterior segment optical coherence tomography (Casia 2; Tomey Corporation).
ACS Macro Lett
September 2025
State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai 200433, China.
Poly(3-hexylthiophene) (P3HT)-based complex topological copolymers have attracted a great deal of attention for their unique electrical and optical properties. In this contribution, the P3HT-based Janus fibers with controlled lengths were innovatively prepared by sequential crystallization-driven self-assembly (CDSA) of poly(--butylstyrene)--polyisoprene--poly(3-hexylthiophene) (PBS--PI--P3HT) triblock copolymer, cross-linking of the interlayer PI region, and dissociation of fibers in good solvent. The comprehensive characterizations showed that the PBS/P3HT Janus fibers have nearly half the width of PBS--PI--P3HT fibers and fiber lengths close to or slightly shorter than those of PBS--PI--P3HT fibers, indicating that the Janus fibers with adjustable lengths could be prepared in a large window range.
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