主权项 |
1. A backside illumination image sensor that includes a semiconductor substrate with a plurality of photoelectric conversion elements formed thereat and a read circuit formed on a side where a front surface of the semiconductor substrate is present, and captures an image by outputting, via the read circuit, electrical signals generated as incident light having passed through an image forming optical system and having reached a side where a back surface of the semiconductor substrate is present, is received at the plurality of photoelectric conversion elements, comprising:
a light shielding film formed on a side where incident light enters the plurality of photoelectric conversion elements, with an opening formed therein in correspondence to each of the plurality of photoelectric conversion elements; and an on-chip lens formed at a position set apart from the light shielding film by a predetermined distance in correspondence to each of the plurality of photoelectric conversion elements, wherein:
the light shielding film and an exit pupil plane at which an exit pupil of the image forming optical system is present achieve a conjugate relation to each other with regard to the on-chip lens, the optical system is separate from the on-chip lens, and a radius of curvature R of the on-chip lens, a distance D from an apex of the on-chip lens to the light shielding film and an average refractive index n of a medium present between the on-chip lens and the light shielding film achieve a relationship expressed as:
D=R·n/(n−1). |