Abstract: The present invention relates to a process and a device for growing single crystals, especially of CaF2. Within the framework of said process, a stack of crucibles (100, 101, . . . , 106, . . . ) containing the starting material is successively moved translationally through a melting chamber (C1) and an annealing chamber (C2), said movement being continuous, smooth and without interruption. The present invention provides for the preparation of fluoride, single crystals, particularly optical fluoride single crystals and optical UV &lgr;<248 nm lithography element blanks, most preferably CaF2.

Abstract: A method and apparatus for aligning optical fibers for splicing utilizing a grooved holder (22) and positioning arms that engage the fiber ends (17, 18) and bring them precisely together in alignment for splicing. The grooves (24, 24′, 26, 26′, 28, 28′) of the holder have a channel (27) extending therebetween. The precisely formed grooves (24, 24′, 26, 26′, 28, 28′) provide X and Y alignment of the fibers in conduction with positioning arms (32, 32′) having resilient pads (36, 36′). The resilient pads (36, 36′) allow the positioning arms (32, 32′) to frictionally engage the optical fibers (15, 16) and bring their respective ends (17, 18) into position for fusion splicing.