| abstract |
(57) [Problem] To provide a material and a method that can sufficiently satisfy a strong demand for further increasing the refractive index of a lens and reducing the edge thickness of the lens. A formula (1) (X) m - (SH) n (1) ( wherein, X represents an alkylene group containing at least one or more of Se atoms, m is 1 to 20, n is 3-6 A trifunctional or higher selenium-containing polythiol represented by the formula: A composition containing the thiol. |