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We have developed anodized-aluminum pressure-sensitive paint (AA-PSP) as a global oxygen sensor in water. Platinum (II) meso-tetra(pentafluorophenyl)porphine is selected as a luminophore based on a dipping deposition study. The developed AA-PSP is characterized using water calibration setup by controlling dissolved oxygen concentration. It is shown that AA-PSP yields 4.0% change in luminescence per 1 mg/L of oxygen concentration at 23°C. Other characteristics, such as temperature dependency, photo-degradation, and physical stability, are discussed in this paper. This AA-PSP is used to demonstrate its capability of global oxygen detection in water using the impingement of oxygen rich water (20 mg/L). Even though the difference in water is only the concentration of oxygen, we can obtain global oxygen information of the jet impingement using a fast frame rate camera. Oxygen maps as well as cross-sectional distributions are shown every 0.1 s.

A reduction is achieved in the number of droplets and/or large particles scattered on the surface of grown film deposited by the pulsed laser deposition method. An aperture plate is placed in front of the ablation target in order to block the scattering of droplets toward the substrate. The angle dependence of the number of scattering droplets is investigated, and the optimum aperture size and substrate position are determined. Using an aperture with 5 mm- diameter hole and placing the substrate in an off-axis position result in a significant reduction of the number of droplets. The aperture is found to prevent the scattering of droplets without substantially diminishing the deposition rate of the film.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A new off-axis pulsed laser deposition method using an aperture plate is proposed for the purpose of depositing high surface-quality Ta2O5 thin films without large fragments and/or droplets. The angular distribution of droplets and growth species emitted from the target is examined. Then, the oxygen pressure and laser energy dependencies of the number of droplets and the film thickness are also examined. The results indicate that the aperture plate plays an important role of limiting the path of the traveling droplets and of capturing the droplets traveling toward the off-axis substrate. On the other hand, the film deposition rate is not slow even when using the plate because the species pass through the aperture hole and reach the substrate by scattering. Using a 5 mm aperture plate, a good surface quality Ta2O5 film is obtained under the optimum condition of 200–300 mTorr oxygen pressure.