PURPOSE: To avoid blur of image due to an overflow phenomenon, by constituting the titled plate so that excessive carriers flow to an excessive carrier absorbing region through potential grooves.

CONSTITUTION: A P- type layer 19 forming a potential groove is provided at a part of a junction between an N type layer 12 being a photodetecting section and a P type layer 13. Even if a strong light is made incident, the excessive carriers flow to the N type layer 11 being the excessive carrier absorbing region via the potential groove of the P- type layer 19, before the excessive carriers flow to the region of the P type layer 13 from the junction between the N type layer 12 and the P type layer 13. Thus, the flowing of the excessive carriers to the adjacent drain region 17 and photodetecting region 12' is prevented.