| 摘要 |
PURPOSE:To facilitate end surface grinding by consisting of a middle part of a polymer mainly made of alkyl acrylate and by increasing conc. of a fluorocarbon resin in proportion to a distance parting from center in circumferen tial direction to decrease refractive index. CONSTITUTION:The rod 1 of a transparent methacrylate is dipped into the solution 2, in which specific weight ratio of PMMA and poly vinylidene fluoride are dissolved, to deposite the blended product 3 with the ratio in specific thickness on the outer circumference of the PMMA rod. Next, after pulled up and dried, the rod is dipped again into the solution 4 having higher conc. of PVDF than the solution 2 to deposite the blend 5 having lower refractive index than the rod 1. The process is repeated successively. As the result, conc. of fluorocarbon resin increases in proportion to the distance parting from center in circumference direction and distribution of refractive index decreasing in radial direction is attained. |
