The authors have developed an approach to fabricate sharp and high aspect ratio metal tips using nanosecond pulse laser melting. A quartz wafer covered with a thin chromium (Cr) film was placed on top of a second wafer with a sub-micrometer gap between them and the Cr film facing the second wafer. Then an excimer laser pulse (308 nm wavelength, 20 ns pulse duration) was shone from the back of t...

BACKGROUND DATA Narrow band ultraviolet B (UVB) is an effective and safe option for the treatment of vitiligo. However, a complete and long-lasting repigmention of vitiligo patches is difficult to achieve. Combined treatments with novel sources of phototherapy and topical agents represent possible new strategies. OBJECTIVE The purpose of this study was to compare the efficacy of combined tacr...

Lasers have proven to be among the most promising tools for micromachining because they can process features down to the size of the laser wavelength (smaller than 1 micrometer) and they provide a non-contact technology for machining. The demand for incorporating in-situ diagnostics technology into the micromachining environment is driven by the increasing need for producing micro-parts of high...

We report time-resolved, quadrupole mass-selected measurements of neutral and ion emission from single crystal sodium nitrate exposed to ns pulse excimer laser radiation at 157 nm (F2 excimer, 7.9 eV photons), 193 nm (ArF excimer, 6.4 eV photons) and 248 nm (KrF excimer, 5.0 eV photons). Neutral emissions, including NO, O2, N2, and Na are observed at all three wavelengths. At 193 nm, intense at...

PURPOSE To present the excimer laser corneal shaping system (ELCS-S), an add-on device to the Keratom, a commercially available 193-nm excimer laser built by Schwind. METHODS The system is designed for the preparation of donor corneas under sterile conditions using the ultraviolet laser to offer greatest possible flexibility. Lenticules for planolamellar grafting and refractive epikeratoplast...

This paper reports on the effects of excimer laser irradiation an aluminum (Al)-doped silicon carbide (4H-SiC) layer. Specifically, high-concentration (1 × 1020 at/cm3) Al-implanted 4H-SiC samples were exposed to a few pulses 308 nm radiation (pulse duration 160 ns), with fluence varying from 1.0 2.8 J/cm2. As starting point, laser-induced modifications morphological, microstructural, and nanoe...

PURPOSE To determine the human corneal threshold ablation energy density for the 193-nm ArF excimer laser, approximating clinical conditions. METHODS The VISX Star (Santa Clara, CA) 193-nm argon fluoride excimer laser was used to ablate the cornea in human eye bank eyes under clinical conditions. Corneas were exposed to energy densities of 10, 20, 30, 35, 40, 45, and 140 to 160 mJ/cm2. Cornea...

today laser has a lot of usage in medicine and dentistry. in the field of dentistry, laser is used in soft tissue surgery, sterilization of canals (in root canal therapy) and in restorative dentistry laser is used for cavity preparation, caries removal, sealing the grooves (in preventive dentistry), etching enamel and dentin, composite polymerization and removal of tooth sensitivity. the use of...

A modified open mask system incorporating an en face air jet to dry the target area during ablation and a conjunctival plication mechanism, which allows ab externo delivery of the 193 nm excimer laser without prior conjunctival dissection, has been developed to form small bore sclerostomies accurately and atraumatically. Full thickness sclerostomies, and sclerostomies guarded by a smaller inter...