| 摘要 |
PURPOSE:To improve a light transmission characteristic and bending characteristic by using a polymethyl methacrylate (PMMA) or the copolymer thereof as a core and using an alpha-olefin random copolymer mixed with a specific tetramethyl-1-pentene as a cladding material. CONSTITUTION:This light transmission fiber is formed by using the PMMA or the copolymer thereof as the core and the alpha-olefin random copolymer mixed with the tetramethyl-1-pentene partly or fully modified by an unsatd. carboxylic acid or the deriv. thereof is formed as the cladding material. The refractive index of the PMMA is 1.491 or the refractive index of the polytetramethyl-1- pentene is 1.463 according to this combination; therefore, the numerical aperture (NA) is 0.288 which is increasingly approximate to 0.22 of a quartz light transmission fiber. The light transmission fiber having 0.28 numerical aperture is thereby put to a practical use and the transmission band is expanded; in addition, the bending resistance is improved. |
