Phonograph record a "De luxe" price. Later, Decca Records introduced vinyl Deccalite 78s, while other record companies used vinyl formulations trademarked as Metrolite, Merco Plastic, and Sav-o-flex, but these were mainly used to produce "unbreakable" children's records and special thin vinyl DJ pressings for shipment to radio stations. In the 1890s, the recording formats of the earliest (toy) discs were mainly 12.5 cm (nominally 5 inches) in diameter; by the mid-1890s, the discs were usually 7 inches (nominally 17.5 cm) in diameter. By 1910, the 10-inch (25.4 cm) record was by far the most popular standard, holding about of music or other
Subwavelength-diameter optical fibre Subwavelength-diameter optical fibre A subwavelength-diameter optical fibre (SDF or SDOF) is an optical fibre whose diameter is less than the wavelength of the light being propagated through it. An SDF usually consists of long thick parts (same as conventional optical fibres) at both ends, transition regions (tapers) where the fibre diameter gradually decreases down to the subwavelength value, and a subwavelength-diameter waist, which is the main acting part. There is no general agreement on how these optical elements are to be named; different groups prefer to emphasize different properties of such fibres, sometimes even using different terms. The names in