| 摘要 |
PURPOSE:To form an optical transmission line for far-infrared light which has less loss by providing a plastic layer which has an index of refraction equal to that of a dielectric on either of the internal and external surfaces of the dielectric as a pipe material, and obtaining a specific relation among the thickness of the plastic layer, thickness of the dielectric, wavelength of far-infrared light, and indexes of refraction of the dielectric and plastic layer corresponding to said wavelength. CONSTITUTION:On either of the external and internal surfaces of the dielectric 2 as the pipe material, the plastic layer 1 having the index of refraction equal to that of the dielectric is provided. Then, the equation holds, where t2 and t1 are the thicknesses of the plastic layer 1 and dielectric, lambda and (n) are the wavelength of far-infrared light and the index of reflection of the dielectric and plastic layer 1 corresponding to the wavelength lambda, and (m) is a constant. |
