Image sensor and imaging device
An imaging element, includes a pixel array in which a plurality of pixels including photoelectric conversion elements are arranged in a two-dimensional array, and an optical element array in which optical elements composed of a plurality of columnar structure bodies arranged opposite to a pixel array and guiding incident light to a corresponding photoelectric conversion element are arranged in a two-dimensional array, wherein the plurality of columnar structure bodies are formed in a width having a phase characteristic for guiding light to a photoelectric conversion element directly below a columnar structure body in accordance with an incident angle of the incident light of each columnar structure body when viewed in a plan view and are formed at a same height when viewed in a side view.
1 . An imaging element, comprising:
a pixel array in which a plurality of pixels including photoelectric conversion elements are arranged in a two-dimensional array; and
an optical element array in which optical elements composed of a plurality of columnar structure bodies arranged opposite to the pixel array and guiding incident light to a corresponding photoelectric conversion element are arranged in a two-dimensional array,
wherein the plurality of columnar structure bodies are formed in a width having a phase characteristic for guiding light to a photoelectric conversion element directly below a columnar structure body in accordance with an incident angle of the incident light of each columnar structure body when viewed in a plan view and are formed at a same height when viewed in a side view;
each of the plurality of columnar structure bodies provides an amount of optical phase delay according to the width of the columnar structure body to the incident light when viewed in the plan view,
in the optical element, the width of each of the plurality of columnar structure bodies when viewed in the plan view is a width providing an optical phase delay amount distribution for guiding the incident light to the photoelectric conversion element directly below the optical element in accordance with a design wavelength of the photoelectric conversion element directly below the optical element and the incident angle (θ, φ) of the incident light,
the θ is an angle between a z-axis as a normal passing through an origin of an x-y plane of the optical element and the incident light incident on the origin of the x-y plane, and
the φ is an angle between an x-axis and a shadow produced by the incident light projected onto the x-y plane of the optical element.
2 . The imaging element according to claim 1 , wherein the plurality of columnar structure bodies are formed of a material having a refractive index higher than that of the material surrounding the plurality of columnar structure bodies and formed in the optical element array at intervals shorter than a wavelength of the incident light.
3 . The imaging element according to claim 1 , wherein the width of each of the plurality of columnar structure bodies when viewed in a plan view is set to provide an optical phase delay amount distribution for guiding the incident light to the corresponding photoelectric conversion element directly below the columnar structure body in accordance with the incident angle of the incident light for each corresponding photoelectric conversion element directly below the columnar structure body.
4 . The imaging element according to claim 1 , wherein the width of each of the plurality of columnar structure bodies when viewed in a plan view is set to have a value different for each wavelength range of the photoelectric conversion element directly below the columnar structure body.
5 . The imaging element according to claim 1 , wherein the optical phase delay amount distribution is an optical phase delay amount for condensing light.
6 . The imaging element according to claim 1 , wherein the plurality of columnar structure bodies are prisms.
7 . The imaging element according to claim 1 , further including:
a transparent layer formed on the pixel array,
wherein the plurality of columnar structure bodies are formed on an upper portion or an inside of the transparent layer with a material having a refractive index higher than that of the transparent layer.
8 . The imaging element according to claim 1 , wherein the plurality of columnar structure bodies have a four-fold rotational symmetry structure when viewed in a plan view.
9 . An imaging device, comprising:
the imaging element according to claim 1 ; and
a signal processing unit, including one or more processors, configured to process an electric signal output using the imaging element and generate an image.
10 . The imaging element according to claim 1 , comprising a transparent layer formed between the pixel array and the optical element array, wherein the plurality of columnar structure bodies are formed inside the transparent layer.
11 . The imaging element according to claim 10 , wherein the transparent layer is air.
12 . An imaging element, comprising:
a pixel array in which a plurality of pixels including photoelectric conversion elements are arranged in a two-dimensional array; and
an optical element array in which optical elements composed of a plurality of columnar structure bodies arranged opposite to the pixel array and guiding incident light to a corresponding photoelectric conversion element are arranged in a two-dimensional array,
wherein the plurality of columnar structure bodies have a refractive index so that they have a phase characteristic for guiding light to the photoelectric conversion element directly below a columnar structure body in accordance with an incident angle of the incident light of each columnar structure body and are formed at a same height when viewed in a side view,
each of the plurality of columnar structure bodies provides an amount of optical phase delay according to a width of the columnar structure body to the incident light when viewed in a plan view,
in the optical element, the width of each of the plurality of columnar structure bodies when viewed in the plan view is a width providing an optical phase delay amount distribution for guiding the incident light to the photoelectric conversion element directly below the optical element in accordance with a design wavelength of the photoelectric conversion element directly below the optical element and the incident angle (θ, φ) of the incident light,
the θ is an angle between a z-axis as a normal passing through an origin of an x-y plane of the optical element and the incident light incident on the origin of the x-y plane, and
the φ is an angle between an x-axis and a shadow produced by the incident light projected onto the x-y plane of the optical element.
13 . The imaging element according to claim 12 , comprising a transparent layer formed between the pixel array and the optical element array, wherein the plurality of columnar structure bodies are formed inside the transparent layer.
14 . The imaging element according to claim 13 , wherein the transparent layer is air.
15 . An imaging device, comprising:
the imaging element according to claim 12 ; and
a signal processing unit, including one or more processors, configured to process an electric signal output using the imaging element and generate an image.