YAG Laser Treatment of Tinea Pedis

A clinical experiment on the treatment of tinea pedis infections (common as an athlete’s foot) was conducted using a pulsed Nd-YAG laser with an output energy of 0.5 joule/pulse and duration of 1 millisecond. The experiment was supported by 13 volunteers for skin samples used in this experiment. The treatment was performed with the following irradiation condition; an energy density of 400 joule/cm2 at a skin sample surface, a spot diameter of the laser beam on the surface of 0.4 mm and a repetition rate of laser pulse shots of 3 Hz. It was shown that the laser treatment was very effective even when a horney laser was thickly cornified by serious tinea pedis; about half of the volunteers were healed with a cure rate of about 70% and, among others, two were cured completely

Studies on CO2 Laser Treatment of Tinea Pedis

An experiment on the treatment of tinea pedis, common athlete’s foot, infections was done using a pulsed CO2 laser having an output energy of 3 joule/pulse and pulse duration of 0.5 μsec. Based on the results by the culture experiment, the ratio of the number of the samples having a cure rate of above 70% to all the samples is about 0.55 for thin skin and 0.35 for thick skin. The itchiness on the blistered infected parts virtually disappear within a few hours after the laser irradiation and the vesicles almost completely disapper within about 2 days

RTS noise reduction of CMOS image sensors using amplifier-selection pixels

This paper describes a RTS (random telegraph signal) noise reduction technique for an active pixel CMOS image sensor (CIS) with in-pixel selectable dual source-follower amplifiers. In this CMOS image sensor, the lower-noise transistor in each pixel is selected in the readout operation using a table of determining the lower-noise transistors of all the pixels. A prototype image sensor with 65×290 pixels for demonstrating the effectiveness of this technique has been implemented using 0.18µm CMOS image sensor technology with pinned photodiode option. The measured result shows that the maximum noise using the amplifier-selection technique is reduced to 9.6e- from 17.2e- which is the maximum noise of the image array using one of two amplifiers in each pixel without selection

Low-Cost Real-Time Gas Monitoring Using a Laser Plasma Induced by a Third Harmonic Q-Switched Nd-YAG Laser

A gas plasma induced by a third harmonic Nd-YAG laser with relatively low pulsed energy (about 10 mJ) has favorable characteristics for gas analysis due to its low background characteristics, nevertheless a high power fundamental Nd-YAG laser (100-200 mJ) is widely used for laser gas breakdown spectroscopy. The air plasma can be used as a low-cost real-time gas monitoring system such that it can be used to detect the local absolute humidity, while a helium plasma can be used for gas analysis with a high level of sensitivity. A new technique using a helium plasma to improve laser ablation emission spectroscopy is proposed. Namely, the third harmonic Nd-YAG laser is focused at a point located some distance from the target in the 1-atm helium surrounding gas. By using this method, the ablated vapor from the target is excited through helium atoms in a metastable state in the helium plasma

Quantitative Analysis of Liquid by Quick Freezing Into Ice Using Nd-YAG Laser-Induced Atmospheric Plasma

A new approach of quantitative analysis of liquid sample using laser ablation technique was developed. The liquid was immediately freezed using the mixture of dry ice and alcohol in weight ratio of 95% : 5%. As a result, an increase of the repulsion force from the sample surface will enable the generation of the laser-induced shock wave plasma which was difficult to carry out on liquid surface. The ice sample was then irradiated using Nd-YAG laser operated in its fundamental wavelength. In order to increase the signal to background ratio and to obtain a sharp atomic line spectra, helium gas was used instead of air. Dynamic characterization of the spatially integrated time profile of the Cu I 521.8 nm, Cu I 510.5 nm and Hα lines shows a shock excitation stage and cooling stage which is corresponded to our shock wave model even when the plasma was generated under atmospheric gas pressure. Further study of the time profile averaged temperature of the atmospheric plasma also shows an increase of temperature during the shock excitation stage followed by diminution of temperature during the cooling stage. An application of this technique was then applied to quantitative analysis of several liquid samples. A linear calibration curve which intercept at 0 point was obtained for all of the elements investigated in this study such as sodium, potassium, lithium, copper, silver, lead and aluminum. A detection limit of around 1 ppm was found for the above element. This new technique will contribute to a great extent of laser atomic emission spectrochemical analysis for liquid samples