Hiromitsu Matsuno

Excitation of solutions in a 2450 MHz discharge

Abstract A 2450 MHz, 400 W discharge in argon was used as an excitation source for spectrochemical analysis. Measurements were made with a wavelength-scanning photoelectric spectrometer. The intensity of the emission from the central axis of the plasma flame was stable to such a degree that the root-mean-square deviation of fluctuations of the background continuum at 4800 A was 0·6% of the total intensity. An excitation temperature of 6400 ± 200°K was obtained on the central axis from the absolute intensity of the H β line. Intensities of the background continuum and the lines which were emitted from the central core of the flame, such as those of arsenic, boron and mercury were little affected by addition of sodium into the plasma, while the lines radiated from the outer zone of the flame, which were mostly of metallic elements, were strongly affected. Detection limits for 25 elements were determined.

Predicted results of a HID DC current lamp considering a P-1 radiation model

This paper presents a numerical model that can be used for designing and/or improving a high-intensity DC discharge lamp. For purposes of illustration, we present results for the plasma subregion considering a 10 A discharge in a mercury-argon mixture (91:9 mass concentrations) operating at 1.1 atm. Calculation is carried out for a simple geometry of lamp, which consists of spherical vessel and ellipsoidal electrodes with a 15 mm interelectrode gap. The steady-state transport equations for mass, momentum, and energy, Laplaces equation for electrostatic potential, Amperes law for magnetic field intensity, the species continuity equation, and the P-1 radiation equation are solved simultaneously for a simple two-dimensional axisymmetric geometry. The buoyancy effect is introduced and the lamp is placed vertically with the anode at the top. We have found a maximum plasma temperature of 10 000 K and a maximum velocity magnitude of 6 m/s near the cathode surface. The values of maximum temperature and velocity are also predicted to be relatively high near the anode surface compared to the values calculated around the middle of the interelectrode gap.

SiO2 thin film preparation using dielectric barrier discharge-driven excimer lamps

Abstract By using a photochemical vapor deposition method with a Xe 2 excimer lamp (172 nm, 20 mW cm −2 output power), silica films have been prepared by means of a single precursor process from Tetraethoxyorthosilicate (TEOS) at room temperature. Transparent thin films of SiO 2 were obtained on sapphire and quartz single crystal substrates with a deposition rate of 0.9 nm min −1 . They were mainly composed of amorphous SiO 2 , although small amounts of residual organic materials were contained. The refractive index was 1.476 at 632.8 nm. The surface roughness decreased with the film thickness and reached 0.2 nm-rms. These findings indicate that the VUV excimer lamp CVD is a promising method for preparing smooth, dense and fine thickness-controllable films of SiO 2 at room temperature.

Br lamp for F2 laser wavelength calibration

Recently, we have developed a novel Br lamp for the F2 laser wavelength calibration. In order to examine the validity of this lamp, we measured emission lines of this lamp in 157 nm region and analyzed them. From our result, it has been confirmed that the spectral profile of the 157.6387 nm (2P3/2 - 4P5/2) emission line of Br atom is unchangeable to the parameters of lamp designs and lamp operating conditions. One of the reasons will be shown here. Hence our novel Br lamp is to be the promising candidate for the 157 nm F2 laser wavelength calibration.

Etching of organic optical materials by photo-material processing using an excimer lamp

A dielectric barrier discharge type Xe excimer lamp has been used for etching of some organic materials which can be widely used for opt-electric applications. Using polymethylmetacrylate (PMMA) and polyimidic (PI) resin as samples, they were irradiated at an intensity of 12 mW/cm2. In both cases, etch rates could be varied by changing the species and pressures of gases in the chamber. The maximum etch rates for PMMA and PI were approximately 7 and 10 nm/min, respectively. The etched surface was found to be very smooth compared to the surfaces etched by the ArF excimer laser. Because the excimer lamp produces incoherent radiation, uniform irradiation over a large area without speckling or interference fringe has been obtained. Furthermore, because the peak power of the lamp is significantly lower than that of excimer lasers, effective quantum effects and photochemical effects without thermal effects have been observed. We applied this technique for etching single crystalline organic opt-electric materials such as 1-arginin phosphate monohydrate and 1-histidine tetrafluoroborate.

Prediction of HID lamp considering P-1 radiation model

Summary form only given, as follows. HID (high intensity discharge) lamps are used in many disciplines including biotechnologies, electronics and telecommunications. Rapid design and development are of key importance in order to shorten the time for a new design to reach the market. Numerical simulation is a cost and time effective solution for fast development. In this paper, we describe a robust simulation package that can be useful in many types of HID lamp designs. The full simulation package consists of several segments to model the electrodes, plasma and glass bulb. Due to space limitations, we focus on the plasma model. The numerical simulation is done for a 2-D axisymmetric geometry assuming that the anode is at the top of the vertically oriented lamp and that the discharge medium is a mercury-argon (10:1 molar concentration ratio) mixture operating at 1.1 atm.

IES Transaction: Compact Lamp with two Interior Fluorescent Tubes

(1984). IES Transaction: Compact Lamp with two Interior Fluorescent Tubes. Journal of the Illuminating Engineering Society: Vol. 14, 1984 IES Annual Conference papers, pp. 298-305.

Luminous Build-up Characteristics of a Compact Fluorescent Lamp with Two Ieparated Inner Tubes

Luminous build-up characteristics of a compact fluorescent lamp with two separated inner tubes have been studied. In this structure, the temperature of the outer bulb, which determines mercury vapor density in the inner tubes, rises gradually after ignition. As a result, the time in which luminous flux reaches a sufficiently high value` is relatively long. It has been found that this luminous build-up is improved by setting silver ribbons near the electrodes. Mercury atoms adsorbed on silver ribbons evaporate since the silver ribbons are heated by radiation from filaments. This results in a rapid increase of the luminous flux after ignition. The surface area of silver necessary for improvement of the luminous build-up has been found to be about 0. 5-v1 cm2 from the measurement of the amount of mercury adsorbed on silved ribbons.