There is a need for providing a variable amplifier circuit suited for a semiconductor integrated circuit and a high-performance camera preprocessing LSI using the variable amplifier circuit. The light module includes one or more emitters of light of at least two different colors that are individually accessible to the one or more drive signals. The receiver housing, angled sidewall and fastening pins only cooperate only when the ball is correctly seated inside the receiver housing and also prevents accumulations of dust and dirt. A data cell identification number of the unit is set according to the recordable time length of one data cell that is designated beforehand and actual recording time length. By this method, impact strength and flame retardancy are recovered or improved.