Papers by Keyword: Optical Storage

Abstract: A new unsymmetrical photochromic diarylethene 1o, which is named [1-(2-methyl-benzothiophene)-2-(2-cyano-1,5-dimethyl-4-pyrryl)]perfluorocyclopentene, was synthesized. We used it to accomplish recording by optical storage technology as memory medium. Then its photochromic both in hexane solution and in PMMA film and kinetics experiment were investigated in detail. The result indicated that this diarylethene had good thermal stability and exhibited reversible photochromism, changing the color from colorless to violet in hexane solution upon appropriate irradiation with 297 nm UV light, respectively. What is more, the kinetic experiments illustrated that the cyclization/cycloreversion process of this compound was determined to be the zeroth/first reaction. The results demonstrated that the unsymmetrical diarylethene compound 1o, which we have synthesized, had attractive properties for potential application in optical storage.

Abstract: A new photochromic diarylethene based on a phenanthrene, which is named 1-{2-methyl-[5-(4-methylene-bromine) phenyl]-3-thienyl}-2-[2-methyl-5-(10-phenanthrenyl)-3-thienyl] perfluorocyclopentene 1o, was designed and constructed successfully. We used it to accomplished recording by optical storage technology as memory medium. And its properties have been discussed systematically, including photochromic both in dichloromethane solution and in PMMA film and kinetics experiments. The result indicated that its photochromic behaviors could be modulated by UV/Vis light, changing between colorless and blue in dichloromethane solution and in PMMA film, respectively. What is more, the kinetic experiments illustrated that the cyclization/cycloreversion process of this compound was determined to be the zeroth/first reaction. In addition, the results demonstrated that the unsymmetrical diarylethene compound 1o, which we had synthesized, had attractive properties for potential application in optical storage.

Abstract: A new unsymmetrical photochromic diarylethene compound 1-[(2-methyl-5-(2-pyridyl)-3-thienyl)]-2-{2-methyl-5-[2-(1,3-dioxolane)]-3-thienyl} perfluorocyclopentene 1O was synthesized. The optoelectronic properties, including photochromism, fluorescences switch and optical recording were investigated in both solution and a PMMA amorphous film. This compound exhibited good photochromism, changing from colorless to purple after irradiation with 297 nm UV light. The new diarylethene also showed remarkable fluorescence switches by photoirradiation in hexane solution. Finally, photo-mode rewritable optical storage using 1C was carried out successfully.

Abstract: A novel unsymmetrical isomeric photochromic diarylethene based on benzofuran, 1-[2-methyl-3-benzofura-2-[2-methyl-5-(10-phenanthrenyl)-3-thienyperfluorocyclopentene, was designed and synthesized. Its fluorescent and photochromic properties were also investigated in detail. The compound exhibited excellent photochromism, changing from colorless to hot pink after irradiation with UV light both in solution and in PMMA film. Furthermore, the fluorescence intensity of the photochromic diarylethene 1a declined remarkably, when irradiation with UV light. Using this diarylethene 1a as optical storage and fluorescence switches was performed successfully.

Abstract: A new unsymmetrical photochromic diarylethene bearing an isoxazole moiety was developed, and its properties, including photochromism, photochromic reaction kinetics, and fluorescence properties were investigated systematically. The compound exhibited remarkable photochromism and functioned as a fluorescent photoswitch both in solution and in PMMA films. The results illustrated that the cyclization processes of diarylethene 1 belong to the zeroth order reaction when open-ring isomers changed to closed-ring isomers and the cycloreversion process belong to the first order reaction. Inaddition, using this diarylethene 1c as optical storage was performed successfully.

Abstract: A new photochromic diarylethene compound, 1-[2-methyl-5-(3-thienyl)-3-thieny-2-[2-methyl-5-(3-benzaldehyde)-3-thieny perfluorocyclopentene (1a) was synthesized. Its properties, including photochromism and fluorescence were investigated in detail both in solution and PMMA amorphous film. It underwent reversible cyclization and cycloreversion reactions upon alternating irradiation with UV and visible light in hexane. The compound showed good phtochromism both in solution and in solid states. Diarylethene 1a changed the color from colorless to navy upon irradiation with 297 nm UV light, in which absorption maxima were observed at 577 nm in hexane and at 592 nm in PMMA film, respectively. Using diarylethene 1b/PMMA film as recording medium, optical recording was performed successfully.

Abstract: When the optical pickup actuator moves, crosstalk force will be generated due to the non-uniformity of the spatial magnetic field, which will consequently affect the dynamic performance of the servo system in optical storage systems. In this paper, the spatial magnetic field model of the actuator is established and the concept of crosstalk degree in both tracking and focusing directions are defined. The relationship between the crosstalk degree and the structure parameters of the actuator such as the height, width and length of the permanent magnet are further analyzed, based on which the optimal structure parameters of the actuator are obtained.

Abstract: A new unsymmetrical isomeric photochromic diarylethene, 1-[2-methyl-3-benzothiophen-2-[2-methyl-5-(10-phenanthrenyl)-3-thienyperfluorocyclopentene, was designed and synthesized. Its photochromic and fluorescent properties were also investigated in detail. The compound exhibited excellent photochromism, changing from colorless to medium violetred after irradiation with UV light both in solution and in PMMA film. Furthermore, the fluorescence intensity of the photochromic diarylethene 1a declined remarkably, when irradiation with UV light. Using this diarylethene 1a as optical storage and fluorescence switches was performed successfully.

Abstract: A novel photochromic diarylethene，1-(3,5-dimethyl-4-isoxazolyl)-2-[2-methyl-5-(10-phenanthrenyl)-3-thienyl]Perfluorocyclopentene was synthesized and its photochromic and fluorescent properties were also investigated. The compound exhibited remarkable photochromism, changing from colorless to pink after irradiation with UV light both in solution and in PMMA film. The fluorescence intensity declined remarkably，when irradiation with UV light. Using this diarylethene 1 as optical storage was performed successfully.

Abstract: A new unsymmetrical photochromic diarylethene, 1-(3,5-dimethyl-4-isoxazolyl)-2-[2-methyl-5-(4-formylphenyl)-3- thienyl]perfluorocyclopentene(1a) were synthesized, and its properties, such as photochromism and fluorescence properties, were investigated in detail. The results showed that this compound had good thermal stability and exhibited reversible photochromism, changing from colorless to darkred after irradiation with UV light both in solution and in PMMA amorphous film, the maxima absorption of its closed-ring isomer 1b are 529 nm and 541 nm respectively. The open-ring isomer of the diarylethene 1a exhibited relatively strong fluorescence at 492 nm in hexane solution (2 × 10^-5 mol/L) when excited at 418 nm. The fluorescence intensity decreased along with the photochromism upon irradiation with 297 nm light. This new photochromic system also exhibited remarkable optical storage character.