Papers by Keyword: Optical Recording

Abstract: In this paper the possibility of using the novel polymeric photosensitive medium for the fabrication of integrated optics elements was demonstrated. The medium is based on PMMA doped by beta-diketonatoboron difluorides. Planar and strip waveguides with the attenuation losses less than 1.8 dB/cm were fabricated in the layer of the medium. The photoinduced recording of the diffraction grating with the spatial frequency up to 3000 mm^-1 and diffraction efficiency ~5% in such waveguides was demonstrated. The possibility to improve the diffraction efficiency of recorded gratings up to 51% by chemical treatment was demonstrated.

Abstract: A novel photochromic diarylethene, 1-(2,5-dimethyl-thienyl)-2-[2-methyl-5-(10-phen-anthrenyl)-3-thienyPerfluorocyclopentene was designed and synthesized, and its photochromic and fluorescent properties were also investigated in detail. The compound exhibited remarkable photochromism, changing from colorless to violet 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 1o as optical storage was performed successfully.

Abstract: A new unsymmetrical photochromic diarylethene, 1-{2-methyl-5-[5-(2,3,5-trihydroxyl-β-D-xylosyl)-3-(1,2,3-triazolyl)] methylene-3-thienyl}-2-[2-methyl-5-(4-methoxylphenyl) methyl-3-thienyl] perfluorocyclopentene (1a), was synthesized, and its photochromic properties were investigated in detail. The compound exhibited good photochromism both in acetonitrile solution and in PMMA film with alternating irradiation by UV/vis light, and the maxima absorption of its closed-ring isomer 1b are 556 and 560 nm, respectively. There almost no fluorescence switches of 1a in acetonitrile solution and PMMA amorphous film. The diarylethene 1a has promising application for photo-switching, which can use for data storage.

Abstract: A novel unsymmetrical diarylethene derivative containing thiophene moieties, in which a methoxy group was substituted at the para-positions of the terminal phenyl ring, was synthesized. Its photochromic properties were investigated in detail, the results indicated that the diarylethene 1o changed the color from colorless to blue, which the absorption maxima were observed at 611 and 627 nm in hexane and PMMA film when irradiation with 297 nm UV light. Additionally, the open-ring isomer of the diarylethene 1o exhibited relatively strong fluorescence at 305 nm in hexane when excited at 322 nm and the fluorescence intensity progressively decreased accompany with the photocyclization occurs. Finally, using this diarylethene as recording medium, polarization optical recording was carried out successfully.

Abstract: A novel photochromic diarylethene 1-{[2-methyl-5-formyl-3-thieny}-2-[2-methyl-5-(2-cyanophenyl)-3-thienyperfluorocyclopentene (1o) has been synthesized for the examination of its properties including photochromism, fluorescence properties and optical recording. The concentration effect in hexane solution was investigated also. The result indicated that the diarylethene 1o changed the color from colorless to royalblue upon irradiation with 297 nm UV light, in which absorption maxima were observed at 592 and 603 nm in hexane and PMMA film, respectively. The colorless open form with fluorescence character could be regenerated by irradiation with visible light. In hexane solution, when the concentration at 2 × 10^-5 mol/L the fluorescence peak have the maximum. The cyano group and its substituted position can availably modulate the optical and electrochemical behaviours of these diarylethene derivatives. In addition, polarization optical recording using this diarylethene as recording medium was performed successfully.

Abstract: Photochromic molecules are part of a large class of materials in which light stimulus not only induces a color variation but also affects other physicochemical properties. In the paper, an asymmetrical photochromic diarylethene, 1-(2,4-dimethyl-3-thiazole)-2-[2-methyl-5-(10-phenanthrenyl)-3-thienyPerfluorocyclopentene was synthesized and its photochromic and fluorescent properties were systematically investigated. The compound exhibited remarkable photochromic, changing from colorless to OrangeRed after irradiation with UV light both in solution and in PMMA film. In addition, its fluorescence property was also discussed. When irradiation with UV light, the fluorescence intensity declined remarkably. The results showed that the diarylethene exhibited a relatively strong fluorescence switch along with the photochromism from open-ring isomer to closed-ring isomer. Using this diarylethene 1a as optical storage was performed successfully.

Abstract: A novel unsymmetrical photochromic diarylethene, 1-[2-methyl-5-(3,5-difluorophenyl)- 3-thienyl]-2-(2-methyl-5-formyl-3-thienyl) perfluorocyclopentene (1) has been synthesized. Its photochromic and properties have been investigated in detail. Specifically, photochromism in solution and in polymethylmethacrylate (PMMA) amorphous films were studied. The results showed that this compound exhibited reversible photochromism, changing from colorless to blue after irradiation with UV light both in solution and in PMMA amorphous film. The photochromic reaction kinetics indicated that the cyclization processes of 1 belong to the zeroth order reaction and the cycloreversion process belong to the first order reaction. In addition, photomode rewritable optical storage using 1b was performed. The images demonstrated that the compound can be used as optical storage material.

Abstract: A reversible molecule switching of symmetrical photochromic diarylethene 1,2-bis methyl phenyl perfluorocyclopentene has been synthesized and its photochromic and simulated molecule structure were also investigated. The compound exhibited photochromism both in solution and PMMA film but no photochromism in solid state. In hexane, the open-ring isomer of the diarylethene 1o showing an absorption peak at 308 nm. Upon irradiation with 313 nm light, a new absorption band in the visible region centered at 595 nm emerged to form closed isomer 1c. This compound can be used as optical recording materials.

Abstract: A new photochromic diarylethene bearing thiophene and naphtyl unit 1-(2-methyl-1-naphthyl)-2-[2-methyl-5-(2-cyanophenyl)-3-thienyl]perfluorocyclopentene (1o), was synthesized and its phtochromic, fluorescence, kinetics and optical recording properties were investigated in detail. This compound exhibited remarkable photochromism, changing from colorless to red after irradiation with 297 nm UV light both in solution and in PMMA film. Finally, using diarylethene 1c as recording medium, polarization optical recording was carried out successfully.

Abstract: A novel photochromic diarylethene 1-{[2-methyl-5-formyl-3-thienyl]}-2-[2-methyl-5-(4-cyanophenyl)-3- thienyl]perfluorocyclopentene(1a) has been synthesized for the examination of its properties including photochromism， fluorescence properties and optical recording. Diarylethene 1a changed the color from colorless to cadet blue upon irradiation with 297 nm UV light, in which absorption maxima were observed at 600 nm in hexane and at 610 nm in PMMA film, respectively. The open-ring isomer of the diarylethene 1 exhibited good fluorescence switch in hexane solution. In hexane solution, the open-ring isomer of the diarylethene 1a exhibited relatively fluorescence at 383 nm when excited at 310 nm.