| 摘要 |
PURPOSE: To prevent a change in black reference level due to a light blocking pixel by forming a potential barrier. CONSTITUTION: Sources or drains 14 of transistors, and photodiodes 13 which constitute light blocking pixel covered by a light blocking layer 16 are formed in a surface of a highly doped well 20 formed in a lightly doped substrate 11, forming the potential barrier ΔV from the lightly doped substrate 11 toward the heavily doped well 20. Even if spot light of a strong intensity is incident into part of a light receiving pixel, causing part of light 17 to reach a neutral region of the lightly doped substrate 11, part of diffused charges 18 which have been subjected to photoelectric transfer in there are prevented from entering the heavily doped well 20 because there is the potential barrier. Consequently, an output signal level of the light blocking pixel never changes, resulting in keeping the black reference level as it is.
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