Polarization image sensor and endoscope

摘要

A polarization image sensor includes: photodiodes arranged on an image capturing plane; a color mosaic filter in which color filters in multiple different colors are arranged to face the photodiodes; an optical low-pass filter which covers the color mosaic filter; and polarization optical elements located closer to a light source than the optical low-pass filter is. Each polarization optical element covers an associated one of the photodiodes and makes light which is polarized in a predetermined direction in a plane that is parallel to the image capturing plane incident onto the optical low-pass filter. The color filters are arranged so that light that has passed through polarization optical elements is transmitted through an associated one of the color filters in a single color. Each color filter covers multiple photodiodes.

主权项

1. A polarization image sensor comprising:
a plurality of photodiodes which are arranged on an image capturing plane and each of which converts light into an electrical signal; a color mosaic filter in which color filters in multiple different colors are arranged so as to face the photodiodes; an optical low-pass filter which covers the color mosaic filter; and a plurality of polarization optical elements which are located closer to a light source than the optical low-pass filter, wherein each of the polarization optical elements covers an associated one of the photodiodes and makes light which is polarized in a predetermined direction in a plane that is parallel to the image capturing plane incident onto the optical low-pass filter, wherein the color mosaic filter has a structure in which a plurality of color filters in multiple different colors are arranged two-dimensionally, the color filters being arranged so that light that has passed through a plurality of polarization optical elements is transmitted through an associated one of the color filters in a single color, each said color filter covering a plurality of photodiodes, and wherein the optical low-pass filter is configured to shift at least a part of a light ray that has been transmitted through each of the polarization optical elements parallel to the image capturing plane by at least the arrangement pitch of the color filters in the color mosaic filter.