Image sensor comprising a color splitter with two different refractive indexes

Abstract

The disclosure relates to an image sensor comprising pixels for acquiring color information from incoming visible light, wherein said image sensor comprising at least two pixels being partially covered by a color splitter structure comprising a first part and a second part, each of said first and second parts being adjacent to a dielectric part, each of said dielectric part having a first refractive index n(said first part having a second refractive index n, and said second part having a third refractive index n, wherein n<n<n, and wherein according to a cross section, the first part of said color splitter structure has a first width W, a height H and the second part of said color splitter structure has a second width W, and the same height H, and wherein said color splitter structure has a first, a second and a third edges at the interfaces between parts having different refractive indexes, each edge generating beams or nanojets, and wherein said height H is close to a value Formul (I), where Θand Θare tan Θand are respectively radiation angles of a first and a third beams generated by said first and third edges, and wherein one of said at least two pixels records light associated with a first wavelength λ-and the other of said at least two pixels records light having a spectrum in which no or few electromagnetic waves having a wavelength equal to λ-are present, wherein said first wavelength λ-being either high or small in a range of visible light.