dichronic particles are developed for a window which varies the degree of light transmission at a user &# 39 ; s desire , wherein the particles are obtained by reacting metal complexes of a transition metal and picolinic acid with polyiodine , dispersing into the particles an acrylate based polymer resin containing a plasticizer and injecting the particles between two conductive sheets of glass to be used for a window which varies the degree of light transmission in presence of electric field , to thereby improve stability to long exposure , color fastness , anti - clusteration , rapid changes in the degree of light transmission in the cases of absence and presence of electric field or power .