Open Air Fabrication of Al2O3 Thin Films at Room Temperature

1996 ◽  
Vol 451 ◽  
Author(s):  
T. Okamoto ◽  
K. Toyoda ◽  
M. Murahara
Keyword(s):  
Excimer Laser ◽  
Pure Aluminum ◽  
Fused Silica ◽  
Active Oxygen ◽  
Aluminum Substrate ◽  
Entrance Window ◽  
Excimer Lamp ◽  
Before And After ◽  
Modified Surface ◽  
Fused Silica Glass

ABSTRACTA thin layer of water or hydrogen peroxide solution, which was formed on a pure aluminum substrate, was photodissociated by ArF excimer laser( λ =193nm) or Xe2* excimer lamp (λ = 172nm) light to photochemically oxidize the surface of aluminum substrate. The layer was formed by a capillary phenomenon between the substrate and a fused silica glass as an entrance window of ultraviolet light. Then, the layer was photodissociated by the excimer laser or the excimer lamp light irradiation to generate active oxygen; the surface oxidization was performed by the photo-induced active oxygen. The surface before and after modification was evaluated by the XPS analysis; the high densed photo-oxidization film was confirmed on the modified surface, compared with a natural oxidization film Furthermore, the contact angle with water became remarkably small, and it is seen that the treated surface was quite densely oxidized.

Photochemical Bonding of Fluorocarbon and Fused Silica Glass for Ultraviolet Ray Transmitting

2003 ◽  
Vol 796 ◽  
Author(s):  
Kenji Asano ◽  
Masataka Murahara
Keyword(s):  
Tensile Strength ◽  
Silica Glass ◽  
Silicone Oil ◽  
Unsaturated Polyester ◽  
Fused Silica ◽  
Strong Absorption Band ◽  
Excimer Lamp ◽  
Silicon Oil ◽  
Fused Silica Glass ◽  
Uv Rays

ABSTRACTFluorocarbon was photo-chemically combined to a fused silica glass with the silicon oil used as a bonding agent. Balsam, unsaturated polyester resins and UV hardening adhesives have been generally used for joining two optical glasses together. They, however, have a strong absorption band in the UV region. Therefore, a new bonding method was developed for optical materials to allow UV rays to pass through using silicone oil and excimer- lamp. This new method requires the fluorocarbon-polishing pad employed in our PCP (Photo-Chemical Polishing) method in hydrofluoric acid ambience, which is bonded with the silica glass. The silicone oil was put between the fused silica glass and the fluorocarbon (FEP), and an excimer- lamp was irradiated. When the excimer lamplight was irradiated vertically, the silicon oil ((-O-Si(CH3)-O-)n) was photo-dissociated and reacted with the oxygen adsorbed on the silica glass surface to produce a SiO2. On the other hand, the H atoms photo-dissociated from the silicon oil pulled out the F atoms of the FEP. As a result, the FEP and the silica glass were combined. The tensile strength of the sample bonded by the photo-chemical reaction was evaluated. The tensile strength of 5.4 [kgf/cm2] was obtained, whereas that of the non-treatment sample was nil. Moreover, the transmittance of the vitrified silicone oil was measured at the 193 nm of ArF laser wavelength. It increased by 90.6% from 29.2% without the UV photon irradiation. The results showed that the silicon oil changed to silica glass by the excited oxygen, which improved the UV rays under 200nm transmittance.

Photochemical Adhesion of Fused Silica Glass Lens by Silicone Oil

2004 ◽  
Vol 843 ◽  
Author(s):  
Takayuki Funatsu ◽  
Masanori Kobayashi ◽  
Yoshiaki Okamoto ◽  
Masataka Murahara
Keyword(s):  
Silica Glass ◽  
Silicone Oil ◽  
Fused Silica ◽  
Oxygen Atmosphere ◽  
Side Chain ◽  
Dimethyl Siloxane ◽  
Before And After ◽  
Glass Lens ◽  
Uv Transmittance ◽  
Fused Silica Glass

ABSTRACTThe optical system that is pervious to ultraviolet light of 200nm and under in the wavelength has been developed by putting one silica glass to another with the silicone oil photo-oxidized in oxygen atmosphere.Quartz has siloxane bonds, while silicone oil (dimethyl siloxane) is composed of siloxane bonds of the main chain and methyl groups of the side chain. Therefore, the organic silicone oil has been photo-oxidized by irradiating UV rays in oxygen atmosphere to change into inorganic glass. That is, the silicone oil was poured into the thin gap between the two pieces of silica glass in oxygen atmosphere and was irradiated with the Xe2 excimer lamp while heating at temperature above 150°C. Consequently, the siloxane of the silicone oil was linked with the O atoms that had been absorbed on the glass surface to form SiO2.The UV and IR spectrum analysis was conducted on the silicone oil before and after lamp irradiation. The results revealed that as the time of lamp irradiation increased, the absorption peak of the CH3 group in the region of 2960 cm−1 decreased but the transmittance of the light in the 190nm wavelength conversely became high. The UV transmittance of the silicone oil was 50% before the lamp irradiation; which improved to 87% after the irradiation for 60 minutes. Furthermore, the tensile strength of the bonded sample was measured. It confirmed that the adhesive strength of the silicone oil was enhanced from 0 kgf/cm2 of before-irradiation to 180 kgf/cm2 of after- irradiation.

Adhesive Property Enhancement by Photochemical Modification on Polyimide Sheet Surface by Irradiation with Excimer Lamp

1995 ◽  
Vol 397 ◽  
Author(s):  
T. Okamoto ◽  
K. Hatao ◽  
T. Shimizu ◽  
M. Aoike ◽  
M. Murahara
Keyword(s):  
Water Solution ◽  
Pure Water ◽  
Fused Silica ◽  
Oh Radicals ◽  
Hydrogen Atoms ◽  
Excimer Lamp ◽  
Hydrophilic Property ◽  
Sheet Surface ◽  
Modified Surface ◽  
Photochemical Modification

ABSTRACTPolyimide sheet surface was photochemically modified to be hydrophilic property with Xe2* excimer lamp ( λ =172nm) irradiation and pure water solution. The solution was sandwiched between the surface and fused silica glass. With the excimer lamp irradiation, the solution and the surface were excited; the surface was dehydrogenated by the hydrogen atoms which were photodissociated from pure water and replaced the photodissociated OH radicals. The hydrophilic property of the modified surface was evaluated by measuring the contact angle with water. The replacement of the OH radicals were confirmed by FTIR. The modified surface was bonded to stainless steel with an epoxy resin for evaluation of the adhesive strength by the shearing tensile test. As a result, the adhesion was increased to 1.4 times that of the non-irradiated sample.

Photochemical Micro-pattern Substitution of Functional Groups for Protein Attachment Control

2006 ◽  
Vol 950 ◽  
Author(s):  
Masataka Murahara ◽  
Yuji Sato
Keyword(s):  
Absorption Coefficient ◽  
Excimer Laser ◽  
Area Ratio ◽  
Water Contact ◽  
Oh Groups ◽  
Excimer Lamp ◽  
Micro Pattern ◽  
Pmma Surface ◽  
Modified Surface ◽  
Arf Excimer Laser

ABSTRACTHydrophilic and hydrophobic groups were selectively incorporated on the poly(methyl methacrylate) [PMMA] surface using a Xe2 excimer lamp and ArF excimer laser. With this new technique, a protein adsorption on the PMMA surface can be controlled.PMMA was firstly irradiated with a Xe2 excimer lamp in the presence of perfluoropolyether [PFPE] liquid layer to incorporate CF3 groups, and secondly, the PMMA surface was irradiated by an ArF excimer laser through a patterned reticle in the presence of water to incorporate OH groups or NH2 groups in an ammonia gas ambience. The area ratio of hydrophilic and hydrophobic of the modifying sample was made to 1:3, 1:1, and 3:1. The results showed that the fibrin absorption on the sample with hydrophilic and hydrophobic micro domains depended on the area ratio of the hydrophilic and hydrophobic. The absorption coefficient of the amide band remarkably decreased with increase in water contact angle. Furthermore, it was confirmed that the absorption coefficient of fibrin decreased as the interval of CF3 and OH or NH2 groups was narrowed from 250 to 20 μm, and the fibrin sticking on the modified surface with the 20 μm hydrophilic and hydrophobic micro domains was reduced to one-twenty of that on the untreated sample.

scholarly journals Integrated backscatter-intravascular ultrasound and modification of plaque during excimer laser coronary angioplasty

2021 ◽  
Author(s):  
Satoru Sasaki ◽  
Kenji Nakajima ◽  
Keizo Watanabe ◽  
Yudai Nozaki ◽  
Tadashi Yuguchi ◽  
...  
Keyword(s):  
Intravascular Ultrasound ◽  
Excimer Laser ◽  
Coronary Angioplasty ◽  
Coronary Plaque ◽  
Cross Sectional ◽  
Integrated Backscatter ◽  
Before And After ◽  
Vessel Volume ◽  
Integrated Backscatter Intravascular Ultrasound ◽  
Excimer Laser Coronary Angioplasty

AbstractThis study aims to test the hypothesis that the effect of excimer laser coronary angioplasty (ELCA) not only vaporizes thrombi and their underlying coronary plaque, it also changes their quality. We performed a series of cross-sectional analyses in 52 lesions in 51 patients before and after ELCA with integrated backscatter-intravascular ultrasound (IB-IVUS). The constituent parts of the plaque can be assessed by IB-IVUS (i.e., calcified, fibrous, lipid) according to integrated backscatter values. Minimum lumen diameter, lumen volume and vessel volume expanded after ELCA, while plaque volume did not significantly decrease. There was also a decrease of ‘lipid’ component (35.4–30.3%, P < 0.001) and an increase of IB-IVUS-derived ‘fibrous’ part (34.5–38.3%, P < 0.001). These results may help in understanding plaque change after ELCA. Excimer laser coronary angioplasty seems to contribute to the modification of coronary plaque composition in addition to debulking it.

Spectral Properties of Spatially and Spectrally Partially Coherent Pulsed Beams in Fused-Silica Glass Medium

2010 ◽  
Vol 663-665 ◽  
pp. 108-112
Author(s):  
Chao Liang Ding ◽  
Min Teng ◽  
Zhi Guo Zhao ◽  
Liu Zhan Pan
Keyword(s):  
Spatial Correlation ◽  
Correlation Length ◽  
Silica Glass ◽  
Coherence Length ◽  
Spectral Properties ◽  
Spectral Shift ◽  
Fused Silica ◽  
Partially Coherent ◽  
Spatial Correlation Length ◽  
Fused Silica Glass

Using the coherence theory of non-stationary fields and the method of Fourier transform, the spectral properties of spatially and spectrally partially coherent Gaussian Schell-model pulsed (GSMP) beams in fused-silica glass medium are studied and analyzed numerically. It is shown that the spectral shift takes place, which depends on the position of the field point, spatial correlation length, temporal coherence length and dispersive property of medium, as GSMP beams propagate in fused-silica glass medium. The on-axis spectrum is blue-shifted, and the relative spectral shift increases with increasing propagation distance, and decreases as the spatial correlation length and temporal coherence length increases, and then approaches an asymptotic value. The dispersive property of medium plays an important role in the spectral properties of spatially and spectrally partially coherent beams.

Computer models of micrometeoroid impact on fused silica glass mirrors

2003 ◽  
Vol 29 (1-10) ◽  
pp. 203-214 ◽  
Author(s):  
David Davison ◽  
Burton Cour-Palais ◽  
Xiangyang Quan ◽  
T.J. Holmquist ◽  
Lester M. Cohen ◽  
...  
Keyword(s):  
Silica Glass ◽  
Computer Models ◽  
Fused Silica ◽  
Fused Silica Glass

Evaluation of Corneal Thickness and Endothelial Cells Before and After Excimer Laser Photorefractive Keratectomy

1994 ◽  
Vol 10 (2) ◽  
pp. 137-141 ◽  
Author(s):  
Giovanni Cennamo ◽  
Nicola Rosa ◽  
Eugenia Guida ◽  
Antonio Del Prete ◽  
Adolfo Sebastiani
Keyword(s):  
Endothelial Cells ◽  
Excimer Laser ◽  
Corneal Thickness ◽  
Photorefractive Keratectomy ◽  
Before And After

scholarly journals Cracking Behavior of Fused Silica Glass in Sphere Indentation

2003 ◽  
Vol 46 (3) ◽  
pp. 415-418 ◽  
Author(s):  
Hatsuhiko USAMI ◽  
Kazuto OHASHI ◽  
Shinnya SASAKI ◽  
Junji SUGISHITA
Keyword(s):  
Silica Glass ◽  
Fused Silica ◽  
Cracking Behavior ◽  
Fused Silica Glass
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