| 摘要 |
PURPOSE:To improve optical transmission characteristics, more particularly the optical transmission characteristic in a visible light region and to obtain less colored light emission by holding a specific relation between the transmission loss L500dB/km measured at 500nm wavelength and the transmission loss L660dB/km measured at 660nm wavelength. CONSTITUTION:The relation L500>L660+400 is held between the transmission loss L500dB/km measured at 500nm wavelength and the transmission loss L660dB/ km measured at 660nm wavelength of a plastic optical fiber consisting of polycarbonate as a core and a polymer having the refractive index lower than the refractive index of the core as a sleeve. The transmission loss L660 measured at 660nm wavelength is made preferably <=1,000dB/km. The polycarbonate used as the core is preferably expressed by the formula (1) and is exemplified by the alicyclic polycarbonate of which R is expressed by the formulas (2), (3) and the arom. polycarbonate expressed by the formulas (4), (5). |
