abstract |
A method of making an optical resin, in which a polymerization vessel is filled with solution of a mixture including at least one kind of polymeric monomer or a sol of such polymeric monomer and at least one kind of substance whose solubility parameter and refractive index differ from those of a polymer produced by polymerization of said monomer by 7 1/2 (cal/cm³) or under and 0.001 or more, respectively, and, with heating or irradiation of rays of energy from the periphery of the polymerization vessel, polymerization reaction is caused and developed preferentially from a particular part of solution so that concentration gradient in substances different in refractive index may be caused and thus providing a refractive index continuously changing along a specific direction. The polymerization vessel may be composed of such polymer as swelling and dissolving from the inner wall of the vessel into the solution of mixture. An optical transmitter is obtained by applying thermal stretching to said optical resin after completion of polymerization reaction thereof. Further, after-treatment based on crosslinking reaction is applied to said transmitter for improvement in resistance thereof to heat. |