The laser-induced retinal injury thresholds for repetitive-pulse exposures to 100-μs-duration pulses at a wavelength of 532 nm have been determined for exposures of up to 1000 pulses in an in vivo model. The ED50 was measured for pulse repetition frequencies of 50 and 1000 Hz. Exposures to collimated beams producing a minimal retinal beam spot and to divergent beams producing a 100-μm-diameter ...

In this work, classic intensity formulae were united with an empirical spot-fading model in order to calculate the diameter of a spherical crystal that will scatter the required number of photons per spot at a desired resolution over the radiation-damage-limited lifetime. The influences of molecular weight, solvent content, Wilson B factor, X-ray wavelength and attenuation on scattering power a...

With the ultramicroanalytical system described here we can measure glucose in 1 ML of plasma or serum. The sample is placed on a dry, multilayer film element (Eastman Kodak), where a colored spot about 3.5 mm in diameter develops. The reflectance of these spots is measured with a reflectance digital matrix photometer that was conceived, designed, and constructed in our laboratory. The spot is i...

Resistance spot welding (RSW) is the most popular joining technique used by automotive industries for the manufacture of automobile body structure. In automobile industries, the weight saving effect of replacing steel parts is an important factor in reducing fuel consumption and increasing speed and natural resources savings. In this study, A5052 aluminium alloy sheet having 1 mm thickness were...

BACKGROUND The long-pulsed 1064-nm Nd:YAG laser (employing varying spot sizes, pulse widths, and fluences) has gained popularity for treating lower extremity blue and red vessels that are less than 4 mm in diameter. OBJECTIVE To evaluate the efficacy of high-power 50-ms 1064 Nd:YAG laser in the treatment of class I-III lower extremity vessels. METHODS Ten female patients (mean age of 39 yea...

introduction: acne scar is formed after severe episodes of acne in teen and earlyadult years. several treatment options have been used for depressed acne scars suchas punch grafting, punch excision carbon dioxide (co2) laser etc. moreover, studiesshow that laser skin resurfacing such as co2 fractional can effectively treat depressedacne scars. we investigated the efficacy of fractional co2 lase...

We report on the advanced optical characterizations of microfabricated solid immersion lenses with 2-μm diameter, operating at λ = 642 nm. The main feature, the spot size reduction, has been investigated by applying a focused Gaussian beam of NA = 0.9. Particular illuminating beams, e.g., Bessel-Gauss beams of the zeroth and the first order, a doughnutshape beam and its decompositions, i.e. two...

We investigate the influence of the excitation spot diameter on the laser threshold of a scattering amplifying medium. Fluorescence spectra are recorded from a suspension of TiO(2) scatterers in Sulforhodamine B dye. The threshold pump intensity becomes larger by a factor of 70 if the excitation beam diameter gets close to the mean free path?. This increase is explained by use of a simple model...

The results of a study aimed at determining the most important experimental parameters for automated, quantitative analysis of solid dosage form pharmaceuticals (seized and model ‘ecstasy’ tablets) are reported. Data obtained with a macro-Raman spectrometer were complemented by micro-Raman measurements, which gave information on particle size and provided excellent data for developing statistic...

We present Ytterbium-doped CaF2 as a laser active material with good prospects for high-power operation in thin-disk laser configuration owing to its favorable thermal properties. Thanks to its broad emission bandwidth the material is also suitable for the generation of ultra-short pulses. The properties of the crystal as well as the challenges related to the coating, polishing, mounting and ha...