A back-illuminated sensor chip is disclosed, which includes one or more pixel areas each including a plurality of pixels located in a plane and arranged in a matrix. Each pixel area includes: a central portion consisting of a plurality of first pixels located in vicinity of a center of the pixel area; and a peripheral portion surrounding the central portion and consisting of the other pixels in the pixel area than the first pixels. The plurality of first pixels have a first height in a vertical direction perpendicular to the plane, and the pixels in the peripheral portion have a second height in the vertical direction that is greater than the first height so that the peripheral portion protrudes outward beyond the central portion and is thus located nearer to a light source during imaging than the central portion. As a result, light sensibility of the peripheral portion is increased.