Blue laser dyes

The fluorescence spectra of 2,5-diarylpyrazines have been studied the presence of electron-donating substituents on each aryl group, as in 2,5-bis(p-methoxyphenyl)pyrazine (246), strengthened fluorescence on photoexcitation the fluorescence of 2,5-di(naphthalen-2-yl)pyrazine (247) proved stronger than that of the isomeric 2,5-di(naphthalen-l-yl)pyrazine due to reduced planarity in the latter structure.1288 p-Bis[2-(pyrazin-2-yl)vinyl]benzene (248) proved to be an efficient blue laser dye (emission A-max 438 nm in Me2SO solution) on excitation by a nitrogen laser at 337 nm.1484... 

The search for blue and UV operating sol-gel lasers began in the middle of nineties (Gvishi, 1995) report on spectroscopic study of blue laser dyes. The dyes are didecylpara-polyphenyl heptamer (DDPPH), didecyloxy para-polyphenyl heptamer (DDOPPH), and bisbenzothiazole 3,4-didecyloxy thiophene (BBTDOT) were studied. No laser operation could be detected at that time. 

Saraidarov, T., Kazes, M., Banin, U., and Reisfeld, R. (2006) Blue laser dye spectroscopic properties in sol gel inorganic-organic hybrid films. Opt. Lett., 31 (3), 356-358. 

The second major category of IR fluorescent dyes are the oxazines, as exemplified by the laser dye Oxazine 1 and Nile Blue (Figure 6.16). Probably the major advantage of the oxazines is their photochemical stability, which is typically much better than that of the cyanines or rhodamines.(52) They are synthesized by condensation of the appropriatep-nitrosoaniline derivatives with the corresponding phenol.<45) These dyes... 

In xanthenes, even if all one-photon allowed transitions are also two-photon allowed, the shape of the bands and their relative intensities are very different in the IPA and 2PA spectra [76,78]. This is not the case for other laser dyes and chromophores, for which the two spectra are almost identical (if represented as a function of the total transition energy), showing peaks in the same position and with very similar band shapes. Some example of chromophores in this category are coumarin 307 [78], coumarin 102 [80], 7-hydroxycoumarin [81], lucifer yellow [78], and cascade blue [78]. 

Introduction of an oxygen bridge into the triphenylmethane dye molecule leads to the xanthene dyes. The color is shifted from blue to red. The restricted rotation of the phenyl groups inhibits radiationless de-excitation and gives rise to very strong fluorescence. Rhodamine B (14) is used for dyeing paper [11] and as a laser dye. 

Basic brown 4, dihydrochloride Basic orange 2 Dianisidine Direct blue 1 Direct yellow 11 Manganese sulfate (ous) Vat yellow 4 dye, textiles leather Acid orange 3 dye, thermoplastics Disperse yellow 54 dye, triacetate Disperse blue 72 dye, tunable lasers Basic red 1 dye, varnishes... 

So far, the mostly utilized light sources for LIF are visible lasers from red ray to blue ray, even purple ray. Since the first red diode laser, its main irradiation wavelength is at 635 nm and was used for the detection of Cy-5-labeled anti-ovalbumin microfluidics capillary electrophoresis (CE). The gas laser, solid-state laser, dye laser, and diode laser have been utilized as exciting light source for LIF integration with microfluidics/ nanofluidics for the detection of molecules, particles, as well as cells. 

F.K. Tittel, T. Hofmann, T.E. Sharp, P.J. Wisoff, W.L. Wilson, and G. Szabo, Blue-Green Dye Laser Seeded Operation of a Terawatt Excimer Amplifier in Dye Lasers 25 Years, Vol. 70 Topics in Applied Physics, M. Stuke (ed.) (Springer, Berlin, Heidelberg, 1992), p 141. 

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