Abstract: A yellow dye compound having a structure of following formula (I) is disclosed: wherein R1, R2, R3, and R4, is defined the same as in the specification. The yellow dye compound can be used in ink-jet ink. Also disclosed is a yellow ink composition including the yellow dye compound having the above formula (I).

Abstract: The invention is directed to a method for fabricating a fiber lens, comprising: (a)stripping proper length of the coating layer of a fiber to form a bare fiber portion; (b)cleaning the bare fiber portion; (c)fixing the fiber into a ferrule included in a holder; (d)providing a container filled with a layer of hydrofloride, a layer of oil and a middle mixed layer; (e)immersing the bare fiber portion in the container, wherein the bare fiber portion is etched by the layer of hydrofloride and the fiber is perpendicular to the surface of the layer of oil to form a cone; (f)melting the cone by a plurality of electric arcs to form a fiber lens; and (g)adjusting the relative position between the electric arcs and the cone to form the desired curvature and shape of the fiber lens.