There can be obtained a suitable optical material which has a stable
structure with a rare earth metal ion while maintaining transparency in a
region of from visible light to near infrared light. The optical material
is obtained by curing a fluorine-containing resin composition comprising
(I) a fluorine-containing prepolymer and (II) a compound containing a
rare earth metal ion and/or a rare earth metal element, wherein the
fluorine-containing prepolymer (I) is a curable fluorine-containing
polymer which: (1) is a non-crystalline polymer having a fluorine content
of not less than 25% by weight and (2) has a cure site in a side chain of
the polymer and/or at an end of a trunk chain of the polymer.