used as the transfer voltages when the light sensing element 11 is composed of a region 14 of p type which is different from the conductivity type of the substrate region as mentioned above electrical charges which are in excess and are stored therein will flow into the substrate so that an overflow drain is not necessary to be specifically provided and thus a space saving results in the above described embodiments the invention is applied to a vertical shift register of the interline transfer system solid state area imaging device however the invention can be applied to the horizontal shift register output shift register and also to any other type of solid state area imaging device or other ctd furthermore the invention has been described primarily in a case where the invention is applied to a surface ctd but it can also be applied to a buried type ctd such an example is illustrated in fig9 and 10 wherein a semiconductor substrate 10 of one conductivity type for example a n type silicon substrate can be selectively formed with a region of other conductivity type or p type facing its one surface 10a such that its transfer region 12 and a channel such as.