Optical element and electronic apparatus

Abstract

To provide an optical element which can have an improved light usage efficiency.SOLUTION: The optical element according to an embodiment of the present disclosure includes: a first substrate; a plurality of structures arranged on the first substrate side by side in a first direction; and a medium provided to fill the spaces between the first structures adjacent to each other, the medium having an index of refraction different from that of the first structure. The first structure has a larger width on the first substrate side than on the side opposite to the first substrate side.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to optical elements and electronic devices. [Background technology]

[0002] An optical element has been proposed that includes a transparent substrate and a concave-convex portion that is a multilayer structure having two or more layers provided on the transparent substrate (Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-28083 A Summary of the Invention [Problem to be solved by the invention]

[0004] In optical elements, it is desirable to improve the light utilization efficiency.

[0005] It is desirable to provide an optical element that can improve the light utilization efficiency. [Means for solving the problem]

[0006] An optical element according to an embodiment of the present disclosure includes a first substrate, a plurality of first structures arranged side by side in a first direction on the first substrate, and a medium having a refractive index different from that of the first structures and arranged to fill spaces between the plurality of adjacent first structures. The width of the first structures on the side opposite to the first substrate is smaller than the width of the first structures on the first substrate side. An optical element according to one embodiment of the present disclosure comprises a first substrate, a plurality of first structures, each of which includes a first portion having a rectangular side shape provided on the first substrate and a second portion provided below the first portion on the first substrate, a second structure provided on the first structures for each first structure and having a refractive index different from that of the first structures, and a medium provided around the plurality of first structures and the plurality of second structures on the first substrate, and having a refractive index different from that of the first structures. An optical element according to an embodiment of the present disclosure includes a first substrate, a plurality of first structures arranged side by side in a first direction on the first substrate, and a medium having a refractive index different from that of the first structures and arranged to fill spaces between the plurality of adjacent first structures, the refractive index being smaller in a peripheral portion of the first structures than in a central portion of the first structures. An electronic device according to an embodiment of the present disclosure includes an optical element and a photodetector that receives light incident through the optical element. The optical element includes a first substrate, a plurality of first structures arranged side by side in a first direction on the first substrate, and a medium having a refractive index different from that of the first structures and arranged to fill spaces between the plurality of adjacent first structures. The width of the first structures on the side opposite to the first substrate is smaller than the width of the first structures on the first substrate. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram illustrating an example of a schematic configuration of an electronic device according to a first embodiment of the present disclosure. [Diagram 2] FIG. 2 is a diagram illustrating an example of a cross-sectional configuration of the optical element according to the first embodiment of the present disclosure. [Diagram 3] FIG. 3 is a diagram illustrating an example of a planar configuration of the optical element according to the first embodiment of the present disclosure. [Figure 4] FIG. 4 is a diagram for explaining an example of the refractive index of the optical element according to the first embodiment of the present disclosure. [Diagram 5] FIG. 5 is a diagram for explaining a configuration example of an optical element according to the first modification of the present disclosure. [Figure 6]FIG. 6 is a diagram for explaining a configuration example of an optical element according to Modification 2 of the present disclosure. [Figure 7] FIG. 7 is a diagram for explaining a configuration example of an optical element according to Modification 3 of the present disclosure. [Figure 8] FIG. 8 is a diagram showing an example of a schematic configuration of an electronic device according to a fourth modification of the present disclosure. [Figure 9] FIG. 9 is a diagram illustrating an example of a schematic configuration of an electronic device according to a fourth modification of the present disclosure. [Figure 10] FIG. 10 is a diagram illustrating an example of a cross-sectional configuration of an optical element according to the second embodiment of the present disclosure. [Figure 11] FIG. 11 is a diagram for explaining a configuration example of an optical element according to the fifth modification of the present disclosure. [Figure 12] FIG. 12 is a diagram for explaining another configuration example of the optical element according to the fifth modification of the present disclosure. [Figure 13] FIG. 13 is a diagram illustrating an example of a cross-sectional configuration of an optical element according to the third embodiment of the present disclosure. [Figure 14] FIG. 14 is a diagram illustrating an example of a cross-sectional configuration of an optical element according to the fourth embodiment of the present disclosure. [Figure 15] FIG. 15 is a diagram for explaining a configuration example of an optical element according to the sixth modification of the present disclosure. [Figure 16] FIG. 16 is a diagram for explaining a configuration example of an optical element according to the sixth modification of the present disclosure. [Figure 17] FIG. 17 is a diagram illustrating an example of a cross-sectional configuration of an optical element according to the fifth embodiment of the present disclosure. [Figure 18] FIG. 18 is a diagram illustrating an example of a cross-sectional configuration of an optical element according to the sixth embodiment of the present disclosure. [Figure 19] FIG. 19 is a diagram illustrating an example of a cross-sectional configuration of an optical element according to the seventh embodiment of the present disclosure. [Figure 20] FIG. 20 is a block diagram illustrating an example of the configuration of an electronic device having an imaging device. [Figure 21] FIG. 21 is a block diagram showing an example of a schematic configuration of a vehicle control system. [Figure 22] FIG. 22 is an explanatory diagram showing an example of the installation positions of the outside-of-vehicle information detection unit and the imaging unit. [Figure 23] FIG. 23 is a diagram showing an example of a schematic configuration of an endoscopic surgery system. [Figure 24] FIG. 24 is a block diagram showing an example of a functional configuration of the camera head and the CCU. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. The description will be made in the following order. 1. First embodiment 2. Second embodiment 3. Third embodiment 4. Fourth embodiment 5. Fifth embodiment 6. Sixth embodiment 7. Seventh embodiment 8. Application Examples 9. Application Examples

[0009] <1. First embodiment> 1 is a diagram illustrating an example of a schematic configuration of an electronic device according to a first embodiment of the present disclosure. The electronic device 300 includes an optical system 200, a filter 201, and a photodetector element 202. The optical system 200 includes one or more lenses, and guides light from a measurement target to the photodetector element 202. The electronic device 300 can be used in various electronic devices or optical devices, such as digital still cameras, video cameras, and mobile phones.

[0010] The optical system 200 has an optical element 100 including a substrate 10 and a plurality of structures 20. The optical element 100 is an optical element (optical member) configured using the structures 20, which are nanostructures, as described below. The optical element 100 is a metalens (metamaterial lens). In the example shown in FIG. 1, the plurality of structures 20 are provided on the substrate 10 on the opposite side to the side on which light is incident (i.e., the side from which light is emitted). Note that the plurality of structures 20 of the optical element 100 may be provided on the side of the substrate 10 on which light is incident.

[0011] 1, the optical system 200 may be configured to include a diaphragm 110 (aperture diaphragm). The diaphragm 110 is provided, for example, on the light incident side of the optical element 100. The optical system 200 is, for example, an imaging optical system having the optical element 100 and the diaphragm 110, and may form an image of a subject to be measured on a photodetector element 202.

[0012] The filter 201 is configured to selectively transmit light of a specific wavelength range among the incident light. The filter 201 is, for example, a band-pass filter, and is provided between the optical system 200 and the photodetector element 202. The filter 201 may be an optical filter such as a filter that blocks infrared light (IR-Cut filter) or a low-pass filter. Note that the electronic device 300 does not necessarily have to have the filter 201.

[0013] The photodetector element 202 is an element capable of detecting incident light. The photodetector element 202 has a plurality of pixels including a light receiving element (light receiving section) and is configured to receive the incident light and generate a signal. The photodetector element 202 can receive light transmitted through the optical system 200 and the filter 201 and generate a signal.

[0014] The light detection element 202 is configured, for example, using a semiconductor substrate (for example, a silicon substrate) on which a plurality of pixels are provided. As an example, the light detection element 202 has a pixel section (pixel array) which is a region in which a plurality of pixels are two-dimensionally arranged in a matrix. The light receiving element of each pixel may be configured, for example, by a photodiode (PD). The light receiving element may also be called a photoelectric conversion element (photoelectric conversion section).

[0015] The light detection element 202 captures incident light (image light) from a subject to be measured via an optical system 200 including the optical element 100. As an example, the light detection element 202 is an image sensor. The light detection element 202 (image sensor) is, for example, a complementary metal oxide semiconductor (CMOS) image sensor, a charge coupled device (CCD) image sensor, or the like.

[0016] The photodetector element 202 captures an image of a subject formed by the optical system 200. The photodetector element 202 photoelectrically converts received light (e.g., visible light, infrared light, etc.) to generate a pixel signal. The photodetector element 202 may be configured as an image sensor, a distance measuring sensor, etc. The optical system 200, the filter 201, and the photodetector element 202 may be collectively referred to as an imaging optical system. Furthermore, the filter 201 may be omitted as necessary.

[0017] The light detection element 202 may be configured as a distance measurement sensor capable of measuring distances by a time-of-flight (TOF) method. The light receiving element of each pixel may be an avalanche photo diode (APD). The light receiving element may be configured, for example, by a single-photon avalanche diode (SPAD).

[0018] The light detection element 202 may be a sensor capable of detecting an event, for example, an event-driven sensor (also called an EVS (Event Vision Sensor), an EDS (Event Driven Sensor), a DVS (Dynamic Vision Sensor), etc.) The electronic device 300 is applicable to various electronic devices or optical devices.

[0019] Fig. 2 is a diagram showing an example of a cross-sectional configuration of the optical element according to the first embodiment. Fig. 3 is a diagram showing an example of a planar configuration of the optical element according to the first embodiment. The optical element 100 has a structure 20 provided on a substrate 10 as in the example shown in Figs. 2 and 3. The optical element 100 is a metalens having the structure 20 which is a nanostructure.

[0020] The optical element 100 is an optical element that utilizes metamaterial (metasurface) technology. The optical element 100 is also called a metasurface optical element. The optical element 100 can be configured as a lens such as a lens that collects light or a lens that diffuses light. The optical element 100 has a structure 20 and can be configured to guide incident light to a light detection element 202 side (see FIG. 1).

[0021] The propagation direction of light through the structures 20 of the optical element 100 can be adjusted by the material (refractive index), shape, height, arrangement interval (pitch), etc. of the structures 20. For example, the material, size, etc. of the structures 20 are determined so that light in a wavelength band to be detected is focused on the light detection element 202. Note that the optical element 100 may be configured as an optical element (deflector) that changes the traveling direction of light in a specific wavelength range.

[0022] The multiple structures 20 of the optical element 100 are arranged two-dimensionally in the X-axis direction and the Y-axis direction, for example, as in the examples shown in Figures 2 and 3. As shown in Figure 3, the up-down direction on the paper surface perpendicular to the X-axis direction is the Y-axis direction, and the direction perpendicular to the X-axis and Y-axis is the Z-axis direction. In other figures, directions may be indicated based on the directions of the arrows in Figures 2 and 3.

[0023] The substrate 10 is a substrate (transparent substrate) that transmits light, and is made of, for example, a glass substrate. The substrate 10 (base material) may be made of, for example, SiO2, Fused Silica, BK7, Quartz, or the like, or may be made of a resin substrate. The substrate 10 (base material) may be made of other materials that transmit the light to be measured.

[0024] As shown in Fig. 2, the substrate 10 has opposing surfaces 11S1 and 11S2. The surface 11S2 is the surface opposite to the surface 11S1. In the example shown in Fig. 2, a plurality of structures 20 are disposed on the surface 11S1 of the substrate 10. The structures 20 may be provided on the light incident side of the substrate 10, or on the light exiting side of the substrate 10. The shape of the substrate 10 is not particularly limited, and may be circular, rectangular, or another shape.

[0025] Light from a measurement target is incident on the structure 20 of the optical element 100. The structure 20 is a structure having a size equal to or smaller than a predetermined wavelength of the incident light. The structure 20 has a size equal to or smaller than the wavelength range of the light to be measured, for example. The structure 20 may have a size equal to or smaller than the wavelength range of infrared light, or may have a size equal to or smaller than the wavelength range of visible light.

[0026] The structure 20 is, for example, a columnar (pillar-shaped) structure. As in the example shown in Fig. 2, the structure 20 is provided such that the width (length) of the structure 20 on the side opposite to the substrate 10 is smaller than the width of the structure 20 on the substrate 10 side. The structure 20 can be formed such that the width of the upper end (tip) of the structure 20 is smaller (thinner) than the width of the lower end (bottom) of the structure 20.

[0027] The width of the structure 20 in the X-axis direction (or Y-axis direction) decreases, for example, as it moves away from the substrate 10. It can also be said that the width (thickness) of the structure 20 in the X-axis direction (or Y-axis direction) increases as it moves closer to the substrate 10. As an example, the structure 20 has a parabolic shape as shown in Fig. 2. The structure 20 can have a flat lower surface (bottom surface) and a curved upper surface.

[0028] The width (length) of the structure 20 in the X-axis direction (or Y-axis direction) may monotonically decrease depending on the distance from the substrate 10 in a predetermined section (range). In the example shown in Fig. 2, the width of the structure 20 gradually decreases (becomes thinner) from the lower part to the upper part of the structure 20. It can also be said that the structure 20 has a portion whose width increases (becomes thicker) as it approaches the substrate 10.

[0029] In the example shown in Fig. 2, the optical element 100 has a moth-eye shaped structure 20. The optical element 100 includes a plurality of fine (micro) structures 20 and has a moth-eye structure. The structure 20 having the above-mentioned shape can be formed by using lithography and dry etching. The structure 20 may also be formed by nanoimprinting, electron beam exposure, or the like.

[0030] The shape of the structure 20 is not limited to the above example and can be changed as appropriate. The shape of the structure 20 in a plan view may be a circle or a rectangle. The shape of the structure 20 in a plan view may be an ellipse, a polygon, or another shape.

[0031] The optical element 100 has a medium (protective layer 50) provided around the structures 20. The protective layer 50 is provided so as to fill the spaces between adjacent structures 20. The protective layer 50 is embedded between the structures 20 on the surface 11S1 of the substrate 10. The protective layer 50 can be formed so as to cover the structures 20, as in the example shown in FIG.

[0032] The protective layer 50 (protective member) can be formed so as to entirely cover the multiple structures 20. The protective layer 50 can also be considered as a filling member provided around the structures 20. The structures 20 can also be considered to be provided within the protective layer 50 (filling member) and disposed by replacing a part of the protective layer 50.

[0033] The optical element 100 uses the structures 20, which are nanostructures, to propagate light toward the photodetector element 202. The structures 20 are also called meta-atoms, nano-atoms, nano-posts, nano-pillars, microstructures, etc. The optical element 100 is an optical element (optical member) that guides (propagates) light. The optical element 100 is configured, for example, as a light guide element that can guide light by imparting a phase delay to incident light. In the optical element 100, a plurality of structures 20 are arranged so as to impart a desired phase profile to the incident light.

[0034] 2, the structures 20 of the optical element 100 are pillars (columnar members) and are provided on the surface 11S1 of the substrate 10. The multiple structures 20 are arranged side by side in the X-axis direction with a part of the protective layer 50 in between. As an example, as shown in FIG. 3, the multiple structures 20 are arranged side by side in the X-axis direction and the Y-axis direction intersecting the X-axis direction in a plan view.

[0035] In the optical element 100, for example, structures 20 having different sizes (width, height, cross-sectional area) may be provided depending on the position in the optical element 100. As an example, in the optical element 100, structures 20 having different widths (diameters) may be provided depending on the distance from the center of the optical element 100, as in the example shown in FIG. 3, in order to obtain desired optical characteristics (e.g., light refraction characteristics).

[0036] 3, in a plurality of annular regions (regions R1, R2, and R3 in FIG. 3), the width of the structures 20 becomes smaller (narrower) as the distance from the center of the optical element 100 (i.e., the distance from the optical axis of the optical element 100) becomes longer (larger). Note that in each of the regions R1 to R3, structures 20 of different heights may be arranged according to the distance from the optical axis of the optical element 100 (or the optical system 200), and a plurality of structures 20 may be arranged at different pitches (arrangement intervals).

[0037] In the optical element 100, the plurality of structures 20 may be arranged at intervals equal to or less than a predetermined wavelength of incident light. As an example, in the substrate 10 of the optical element 100, the plurality of structures 20 are provided at intervals equal to or less than the wavelength range of visible light in the X-axis direction and the Y-axis direction. Note that the plurality of structures 20 may be arranged at intervals equal to or less than the wavelength range of infrared light.

[0038] The structure 20 of the optical element 100 has a refractive index different from that of the adjacent medium. In the example shown in Fig. 2, the structure 20 has a refractive index different from that of the protective layer 50. The structure 20 has a refractive index different from that of the medium layer formed around the structure 20, i.e., the protective layer 50.

[0039] The structure 20 of the optical element 100 has, for example, a refractive index higher than that of the protective layer 50. The structure 20 can be made of a material having a refractive index higher than that of the protective layer 50. The structure 20 is made of, for example, titanium oxide (TiO). The structure 20 may also be made of silicon, polysilicon (Poly-Si), amorphous silicon (a-Si), or the like.

[0040] The structure 20 may be made of titanium, hafnium, zirconium, tantalum, aluminum, indium, niobium, or the like, or may be made of an oxide, nitride, oxynitride, or a composite of these. The structure 20 may be made of a metal compound (metal oxide, metal nitride, etc.), or may be made of silicon nitride (Si3N4).

[0041] The structure 20 of the optical element 100 may have a refractive index lower than that of the protective layer 50. The structure 20 may be made of a material having a refractive index lower than that of the protective layer 50, for example, and may have a refractive index lower than that of the protective layer 50.

[0042] The protective layer 50 is, for example, configured using an inorganic material such as an oxide, a nitride, or an oxynitride. The protective layer 50 may be formed of, for example, silicon oxide, silicon nitride, silicon oxynitride, silicon carbide, etc. The protective layer 50 may also be configured using fused silica, BK7, quartz, etc.

[0043] The protective layer 50 may be made of a siloxane-based resin, a styrene-based resin, an acrylic-based resin, or the like. The protective layer 50 may be made of any of these resins containing fluorine. The protective layer 50 may be formed of any of these resins filled with beads having a refractive index higher (or lower) than that of the resin.

[0044] Materials for the structure 20, protective layer 50, etc. of the optical element 100 can be selected according to the refractive index difference with the surrounding medium, the wavelength range of the incident light to be measured, etc. The structure 20 and protective layer 50 of the optical element 100 may be made of an inorganic material or an organic material. The protective layer 50 or the structure 20 may be made of a gap (cavity). For example, the protective layer 50 may be made of air (air layer).

[0045] The optical element 100 can control the wavefront of light by, for example, causing a phase delay in the incident light due to the refractive index difference between the structure 20 and the surrounding medium. The optical element 100 can adjust the propagation direction of light by, for example, imparting a phase delay to the incident light by the structure 20 and the protective layer 50 around the structure 20.

[0046] The materials (optical constants of each material) of the structures 20 and the protective layer 50, the size, shape, pitch (arrangement interval), height, etc. of the structures 20 are determined so that light of a desired wavelength range from the light from the measurement target travels in a desired direction. For example, the material (refractive index), size (width, height, etc.), pitch, shape, etc. of each structure 20 of the optical element 100 are set. As described above, the dimensions, arrangement position, etc. of the structures 20 can be adjusted depending on the position in the optical element 100.

[0047] 1 receives light from an object (subject) to be measured via an optical system 200 including the optical element 100 described above. The light receiving element of each pixel can receive the light incident via the optical element 100 and generate a pixel signal. The electronic device 300 can generate image data indicating an image of the subject, for example, using the pixel signal of each pixel of the light detection element 202. Furthermore, for example, the electronic device 300 can generate image data relating to the distance to the object (distance image data) using the pixel signal of each pixel.

[0048] As described above, the optical element 100 according to the present embodiment has the moth-eye shaped structures 20. Therefore, the effective refractive index of the optical element 100 can be gradually changed. This makes it possible to reduce, for example, the reflection at the interface between the structures 20 and the protective layer 50, and suppress a decrease in the light utilization efficiency.

[0049] In the optical element 100, the structures 20 have a shape that, for example, becomes thinner (smaller) as it moves away from the substrate 10. Therefore, the proportions of the structures 20 and the protective layer 50 in the optical element 100 are adjusted, and the refractive indexes (effective refractive indexes) of the structures 20 and the protective layer 50 can be changed stepwise. The effective refractive index of the optical element 100 can be changed continuously, and reflection in the optical element 100 can be suppressed (reduced).

[0050] 4 is a diagram for explaining an example of the refractive index of the optical element according to the first embodiment. In (A) of FIG. 4, the refractive index n p indicates the refractive index of the structure 20, and the refractive index ne indicates the refractive index of the protective layer 50. Fig. 4(B) shows an example of the refractive index in the optical element 100. As in the example shown in Fig. 4(B), the optical element 100 can have a refractive index (effective refractive index) that changes continuously from the upper end (tip) to the lower end (bottom) of the structure 20, for example.

[0051] In this way, the optical element 100 can be configured to gradually change the effective refractive index by using the structure 20 having a parabolic structure, etc. Therefore, the angle dependency of the reflectance can be reduced. Even when light is incident at an angle to the surface 11S1 (or surface 11S2) of the substrate 10 of the optical element 100, it is possible to suppress the occurrence of interface reflection.

[0052] In the electronic device 300, even when light is obliquely incident on the optical element 100, it is possible to appropriately propagate the incident light to the photodetector element 202. Even in the case of obliquely incident light, diffracted light (converged light) can be appropriately guided to the photodetector element 202. In addition, it is possible to suppress the occurrence of unnecessary reflected light, and to suppress the occurrence of noise and defects (flare, ghost, etc.) in an image due to reflected light. It is possible to prevent deterioration in image quality.

[0053] In addition, in this embodiment, the optical system 200 is configured using the optical element 100, which is a metalens. The optical element 100 is configured, for example, as a lens that collects light. Therefore, compared to an optical system configured using a large number of optical lenses, it can contribute to a low profile of the optical system. It can also contribute to a reduction in the number of components of the electronic device 300 and a miniaturization of the electronic device 300.

[0054] [Actions and Effects] The optical element (optical element 100) according to this embodiment includes a first substrate (substrate 10), a plurality of first structures (structures 20) arranged side by side in a first direction (e.g., the X-axis direction) on the first substrate, and a medium (protective layer 50) having a refractive index different from that of the first structures and arranged to fill the spaces between the plurality of adjacent first structures. The width of the first structures on the side opposite to the first substrate is smaller than the width of the first structures on the first substrate side.

[0055] In the optical element 100 according to the present embodiment, a plurality of structures 20 are provided. The width of the structures 20 on the side opposite to the substrate 10 side is smaller than the width of the structures 20 on the substrate 10 side. This makes it possible to suppress reflection in the optical element 100. It becomes possible to realize an optical element capable of improving the light utilization efficiency.

[0056] Next, a modified example of the present disclosure will be described. In the following, the same components as those in the above embodiment are denoted by the same reference numerals, and the description thereof will be omitted as appropriate.

[0057] (1-1. Variation 1) In the above-mentioned embodiment, the configuration example of the optical element has been described, but the configuration of the optical element is not limited to the above-mentioned example. Fig. 5 is a diagram for explaining the configuration example of the optical element according to the first modification of the present disclosure. The structure 20 of the optical element 100 may have a triangular side shape as in the example shown in Fig. 5. By providing the triangular structure 20, it is possible to change the effective refractive index.

[0058] In the case of the optical element 100 according to this modification, it is also possible to reduce reflection in the optical element 100 and suppress a decrease in light utilization efficiency. In addition, the refractive index at the tip portion of the optical element 100 is approximately the same as the refractive index of the protective layer 50, making it easier to ensure the transmittance characteristics.

[0059] (1-2. Variation 2) Fig. 6 is a diagram for explaining a configuration example of an optical element according to Modification 2. The structure 20 of the optical element 100 may have a trapezoidal side shape as in the example shown in Fig. 6. In this case, the width of the structure 20, i.e., the pillar diameter, can be made relatively large, making it easier to ensure the amount of phase delay. Therefore, the structure 20 with a small height (length) can ensure the necessary phase difference.

[0060] (1-3. Variation 3) Fig. 7 is a diagram for explaining a configuration example of an optical element according to Modification 3. The structures 20 of the optical element 100 may have a parabolic shape. As shown in Fig. 7, the structures 20 may have a shape expressed by the following formula (1) using a height H to a tip of the structures 20 and a width (diameter) D of the structures 20.

number

[0061] Equation (1) is a relational expression between the height Z of the structure 20 and the radius x of the structure 20. By providing the structure 20 having the side shape expressed by equation (1), it is possible to suppress reflection in the optical element 100 even in the case of obliquely incident light. In addition, it is possible to ensure the light utilization efficiency and the phase adjustment amount.

[0062] (1-4. Variation 4) In the above-mentioned embodiment, the configuration examples of the electronic device and the optical system have been described, but the configurations of the electronic device and the optical system are not limited to the above-mentioned examples. Fig. 8 and Fig. 9 are diagrams showing an example of a schematic configuration of an electronic device according to Modification 4. The optical system 200 may be configured to include multiple lenses. For example, as in the example shown in Fig. 8, the optical system 200 may have multiple lenses (lens 121 and lens 122 in Fig. 8).

[0063] The optical system 200 may be configured to include a lens having negative refractive power, a lens having positive refractive power, or the like as the lens 121 or the lens 122. The aperture 110 may be disposed, for example, between the lens 121 and the lens 122. Light from a measurement target is incident on the optical element 100 via the lens 121, the aperture 110, and the lens 122. The light detection element 202 receives incident light from the subject, which is the measurement target, via the optical system 200. The light detection element 202 may capture an image of the subject formed by the optical system 200, for example.

[0064] The optical element 100 may have structures 20a and structures 20b as the structures 20, which are nanostructures, as shown typically in Fig. 9. In the example shown in Fig. 9, the multiple structures 20a are provided on the light exit side of the substrate 10, and the multiple structures 20b are provided on the light entrance side of the substrate 10. It can also be said that the optical element 100 has a metalens including the multiple structures 20a, and a metalens including the multiple structures 20b.

[0065] A metalens having structures 20a and a metalens having structures 20b may be configured to provide different phase profiles to incident light. Structures 20a and structures 20b may be formed to have different sizes (e.g., widths), shapes, arrangement intervals (pitch), etc. Note that structures 20a and structures 20b may be configured using the same material or different materials.

[0066] <2. Second embodiment> Next, a second embodiment of the present disclosure will be described. In the following, the same components as those in the above-described embodiment are denoted by the same reference numerals, and the description thereof will be omitted as appropriate.

[0067] Fig. 10 is a diagram showing an example of a cross-sectional configuration of an optical element according to the second embodiment. As shown in Fig. 10, the structure 20 of the optical element 100 has a portion 21a and a portion 21b. The portion 21a of the structure 20 is provided, for example, on the substrate 10 and has a rectangular side shape. The portion 21b of the structure 20 is provided on the portion 21a.

[0068] The width of portion 21b of structure 20 in the X-axis direction (or Y-axis direction) decreases, for example, as it moves away from portion 21a. It can also be said that the width of portion 21b increases as it approaches portion 21a (or substrate 10). The width (diameter) of portion 21b of structure 20 may monotonically decrease according to the distance from substrate 10. Portion 21b of structure 20 may have a moth-eye shape.

[0069] In the optical element 100 according to the present embodiment, a structure 20 having a portion 21a and a portion 21b is provided. Therefore, the effective refractive index of the optical element 100 can be gradually changed. This can reduce the interface reflection and suppress the decrease in the light utilization efficiency.

[0070] Furthermore, by providing the rectangular region 21a, it becomes easier to ensure the phase adjustment function. The aspect ratio of the nanostructure 20 can be reduced, making it possible to prevent the processing of the structure 20 from becoming difficult in the manufacturing process. It becomes possible to suppress the controllability of the phase profile from decreasing.

[0071] [Actions and Effects] The optical element (optical element 100) according to this embodiment includes a first substrate (substrate 10), a plurality of first structures (structures 20) arranged side by side on the first substrate in a first direction (e.g., the X-axis direction), and a medium (protective layer 50) that is provided so as to fill the spaces between the plurality of adjacent first structures and has a refractive index different from that of the first structures. The first structures are provided on the first substrate, and include a first portion (portion 21a) having a rectangular side shape, and a second portion (portion 21b) provided on the first portion.

[0072] In the optical element 100 according to the present embodiment, a structure 20 having a portion 21a and a portion 21b each having a rectangular side shape is provided. Therefore, reflection in the optical element 100 can be suppressed. It is possible to realize an optical element capable of improving the light utilization efficiency. Furthermore, by providing the portion 21a, which is a rectangular region, it becomes easier to ensure a phase adjustment function. The aspect ratio of the structure 20, which is a nanostructure, can be reduced, and it is possible to prevent the structure 20 from becoming difficult to process in the manufacturing process.

[0073] Next, a modified example of the present disclosure will be described. In the following, the same components as those in the above embodiment are denoted by the same reference numerals, and the description thereof will be omitted as appropriate.

[0074] (2-1. Variation 5) Fig. 11 is a diagram for explaining a configuration example of an optical element according to Modification 5 of the present disclosure. Fig. 12 is a diagram for explaining another configuration example of an optical element according to Modification 5. The portion 21b of the structure 20 of the optical element 100 may have a triangular side shape, for example, as in the example shown in Fig. 11.

[0075] Also, for example, the portion 21b of the structure 20 may have a trapezoidal side shape as in the example shown in Fig. 12. The portion 21b of the structure 20 may have a parabolic shape represented by the above-mentioned formula (1). In the case of this modification, the same effects as those of the above-mentioned embodiment and modification can be obtained.

[0076] <3. Third embodiment> Next, a third embodiment of the present disclosure will be described. In the following, the same components as those in the above-described embodiment are denoted by the same reference numerals, and the description thereof will be omitted as appropriate.

[0077] Fig. 13 is a diagram showing an example of a cross-sectional configuration of an optical element according to a third embodiment. As shown in Fig. 13, a structure 20 of an optical element 100 has a portion 21a provided on a substrate 10 and a portion 21c provided on the substrate 10 below the portion 21a. In the example shown in Fig. 13, the portion 21c is formed in the substrate 10. The portion 21c can be disposed so as to be embedded in the substrate 10.

[0078] The portion 21a of the structure 20 has a width that decreases with increasing distance from the substrate 10 (or portion 21c). The width of the portion 21c of the structure 20 in the X-axis direction (or Y-axis direction) decreases with increasing distance from the portion 21a. It can also be said that the width of the portion 21c increases with increasing distance from the portion 21a. The portions 21a and 21c of the structure 20 may each have a moth-eye shape.

[0079] In the optical element 100 according to the present embodiment, the structure 20 having the portion 21a and the portion 21c is provided. Therefore, it is possible to effectively suppress reflection on the substrate 10 side. It is possible to suppress a decrease in the light utilization efficiency.

[0080] [Actions and Effects] The optical element (optical element 100) according to this embodiment includes a first substrate (substrate 10), a plurality of first structures (structures 20) arranged side by side on the first substrate in a first direction (e.g., the X-axis direction), and a medium (protective layer 50) having a refractive index different from that of the first structures and provided so as to fill the spaces between the plurality of adjacent first structures. The first structures include a first portion (portion 21a) provided on the first substrate, and a second portion (portion 21c) provided below the first portion on the first substrate.

[0081] In the optical element 100 according to the present embodiment, a structure 20 is provided having a portion 21a provided on the substrate 10 and a portion 21c provided on the substrate 10. This makes it possible to effectively suppress reflection in the optical element 100. It becomes possible to realize an optical element capable of improving the light utilization efficiency.

[0082] <4. Fourth embodiment> Next, a fourth embodiment of the present disclosure will be described. In the following, the same components as those in the above-described embodiment are denoted by the same reference numerals, and the description thereof will be omitted as appropriate.

[0083] Fig. 14 is a diagram showing an example of a cross-sectional configuration of an optical element according to the fourth embodiment. As shown in Fig. 14, a structure 20 of an optical element 100 has a portion 21a provided on a substrate 10, a portion 21b provided on the portion 21a, and a portion 21c provided on the substrate 10 below the portion 21a.

[0084] The portion 21a of the structure 20 has, for example, a rectangular side shape. The portion 21b of the structure 20 has a width that decreases with increasing distance from the substrate 10 (or the portion 21a). The portion 21c of the structure 20 has a width that decreases with increasing distance from the portion 21a.

[0085] In the optical element 100 according to the present embodiment, a structure 20 having a portion 21a, a portion 21b, and a portion 21c is provided. Therefore, reflection on the substrate 10 side can be effectively suppressed. It is possible to suppress a decrease in light utilization efficiency. In addition, it is possible to reduce the aspect ratio of the structure 20 by the same effect as in the second embodiment.

[0086] [Actions and Effects] The optical element (optical element 100) according to this embodiment includes a first substrate (substrate 10), a plurality of first structures (structures 20) arranged side by side on the first substrate in a first direction (e.g., the X-axis direction), and a medium (protective layer 50) that is arranged to fill the spaces between the plurality of adjacent first structures and has a refractive index different from that of the first structures. The first structures are arranged on the first substrate and include a first portion (portion 21a) having a rectangular side shape, a second portion (portion 21b) arranged on the first portion, and a third portion (portion 21c) arranged on the first substrate below the first portion.

[0087] In the optical element 100 according to the present embodiment, a structure 20 having the portions 21a to 21c is provided. This makes it possible to effectively suppress reflection in the optical element 100. It becomes possible to realize an optical element capable of improving the light utilization efficiency.

[0088] Next, a modified example of the present disclosure will be described. In the following, the same components as those in the above embodiment are denoted by the same reference numerals, and the description thereof will be omitted as appropriate.

[0089] (4-1. Variation 6) 15 and 16 are diagrams for explaining a configuration example of an optical element according to the sixth modification of the present disclosure. The portion 21b and the portion 21c of the structure 20 of the optical element 100 may have a triangular side shape as in the example shown in FIG. 15. The portions 21b and 21c of the structure 20 may have a trapezoidal side shape as in the example shown in FIG. 16. The portions 21b and 21c of the structure 20 may have a parabolic shape represented by the above-mentioned formula (1). In the case of this modification, the same effects as those of the above-mentioned embodiment and modifications can be obtained.

[0090] <5. Fifth embodiment> Next, a fifth embodiment of the present disclosure will be described. In the following, the same components as those in the above-described embodiment are denoted by the same reference numerals, and the description thereof will be omitted as appropriate.

[0091] Fig. 17 is a diagram showing an example of a cross-sectional configuration of an optical element according to the fifth embodiment. As shown in Fig. 17, the optical element 100 may have a structure 30. The structure 30 is a nanostructure and has, for example, a refractive index different from that of the structure 20 and the protective layer 50. As an example, the structure 30 is made of a metal compound (metal oxide, metal nitride, etc.) and is provided on the surface 11S1 of the substrate 10. Note that the structure 30 may be formed using other materials.

[0092] 17, the structure 30 is provided between the substrate 10 and the portion 21a of the structure 20, and reduces (suppresses) reflection. The structure 30 may be provided, for example, under each structure 20. The structures 20 and 30 are provided by stacking them on each other. The structure 30 may have a refractive index higher than that of the structure 20, or may have a refractive index lower than that of the structure 20. The structure 30 may also be called an anti-reflection member (reflection suppression member).

[0093] The protective layer 50 is provided around the structures 20 and 30, for example, as in the example shown in FIG. 17. The protective layer 50 can be made of, for example, a material having a refractive index different from the refractive indexes of the structures 20 and 30. The portion 21a of the structure 20 is provided, for example, on the structure 30 and has a rectangular side shape. Furthermore, the portion 21b of the structure 20 is provided on the portion 21a. The portion 21b of the structure 20 has a width that decreases with increasing distance from the substrate 10 (or the portion 21a).

[0094] [Actions and Effects] The optical element (optical element 100) according to this embodiment includes a first substrate (substrate 10), a plurality of first structures (structures 20) arranged side by side on the first substrate in a first direction (e.g., the X-axis direction), and a medium (protective layer 50) having a refractive index different from that of the first structures and provided so as to fill the spaces between the plurality of adjacent first structures. The optical element further includes a second structure (structure 30) provided between the first substrate and the first structures and having a refractive index different from that of the first structures.

[0095] In the optical element 100 according to the present embodiment, the structure 30 having a refractive index different from that of the structure 20 is provided between the substrate 10 and the structure 20. This makes it possible to effectively suppress reflection in the optical element 100. It becomes possible to realize an optical element capable of improving the light utilization efficiency.

[0096] <6. Sixth embodiment> Next, a sixth embodiment of the present disclosure will be described. In the following, the same components as those in the above-mentioned embodiment will be denoted by the same reference numerals, and the description will be omitted as appropriate.

[0097] Fig. 18 is a diagram showing an example of a cross-sectional configuration of an optical element according to the sixth embodiment. As shown in Fig. 18, the optical element 100 may have a structure 20 having a portion 21a and a portion 21c, and a structure 30 provided on the structure 20. The structure 30 may be provided on the structure 20 for each structure 20, for example. The structure 20 and the structure 30 are provided by stacking them on each other.

[0098] The structure 30 has, for example, a refractive index different from that of the structure 20 and the protective layer 50. The structure 30 is provided on the portion 21a of the structure 20 and reduces reflection. The structure 30 is an anti-reflection member (reflection suppressing member). Note that the structure 30 may have a refractive index higher than that of the structure 20, or may have a refractive index lower than that of the structure 20.

[0099] The protective layer 50 is made of, for example, a material having a refractive index different from the refractive indexes of the structures 20 and 30. The protective layer 50 can be formed so as to cover the structure 30. The portion 21a of the structure 20 is provided, for example, on the substrate 10 and has a rectangular side shape. The portion 21c of the structure 20 is provided below the portion 21a within the substrate 10. The portion 21c of the structure 20 has a width that decreases with increasing distance from the portion 21a.

[0100] [Actions and Effects] The optical element (optical element 100) of this embodiment comprises a first substrate (substrate 10), a plurality of first structures (structures 20), each of which includes a first portion (portion 21a) having a rectangular side shape provided on the first substrate and a second portion (portion 21c) provided below the first portion on the first substrate, a second structure (structure 30) provided on the first structure for each first structure and having a refractive index different from the refractive index of the first structure, and a medium (protective layer 50) provided around the plurality of first structures and the plurality of second structures on the first substrate, and having a refractive index different from the refractive index of the first structures.

[0101] In the optical element 100 according to the present embodiment, a structure 30 having a refractive index different from that of the structure 20 is provided on the structure 20. This makes it possible to effectively suppress reflection in the optical element 100. It becomes possible to realize an optical element capable of improving the light utilization efficiency.

[0102] <7. Seventh embodiment> Next, a seventh embodiment of the present disclosure will be described. In the following, the same components as those in the above-described embodiment will be denoted by the same reference numerals, and the description will be omitted as appropriate.

[0103] Fig. 19 is a diagram showing an example of a cross-sectional configuration of an optical element according to a seventh embodiment. As shown in Fig. 19, the optical element 100 has a structure 20 which is a nanostructure. The structure 20 according to this embodiment is a nanostructure having a refractive index distribution. As shown in Fig. 19, for example, the refractive index in the peripheral part of the structure 20 is smaller than the refractive index in the center part of the structure 20.

[0104] The structure 20 may be made of an inorganic material such as a metal compound, or may be made of an organic material. The structure 20 may be formed using beads (filler). The structure 20 may be configured so that the refractive index in the center portion of the structure 20 is lower than the refractive index in the peripheral portion (end portion) of the structure 20.

[0105] In the present embodiment, the effective refractive index can be continuously changed by providing the structures 20. This makes it possible to reduce reflection in the optical element 100 and suppress a decrease in light utilization efficiency.

[0106] [Actions and Effects] The optical element (optical element 100) according to this embodiment includes a first substrate (substrate 10), a plurality of first structures (structures 20) arranged side by side in a first direction (e.g., the X-axis direction) on the first substrate, and a medium (protective layer 50) having a refractive index different from that of the first structures and provided so as to fill the spaces between the plurality of adjacent first structures. The refractive index in the periphery of the first structures is smaller than the refractive index in the center of the first structures.

[0107] In the optical element 100 according to the present embodiment, a plurality of structures 20 are provided. The refractive index in the peripheral portion of the structure 20 is smaller than the refractive index in the central portion of the structure 20. Therefore, it is possible to suppress reflection in the optical element 100. It is possible to realize an optical element capable of improving the light utilization efficiency.

[0108] <8. Application Examples> The electronic device 300 and the like can be applied to any type of electronic device equipped with an imaging function, such as a camera system such as a digital still camera or a video camera, or a mobile phone with an imaging function. FIG. 20 shows a schematic configuration of the electronic device 1000.

[0109] The electronic device 1000 includes, for example, a lens group 1001, an imaging device 1, a DSP (Digital Signal Processor) circuit 1002, a frame memory 1003, a display unit 1004, a recording unit 1005, an operation unit 1006, and a power supply unit 1007, which are interconnected via a bus line 1008.

[0110] The lens group 1001 captures incident light (image light) from a subject and forms an image on the imaging surface of the imaging device 1. The imaging device 1 converts the amount of incident light formed on the imaging surface by the lens group 1001 into an electrical signal on a pixel-by-pixel basis and supplies the signal to the DSP circuit 1002 as a pixel signal.

[0111] The DSP circuit 1002 is a signal processing circuit that processes a signal supplied from the imaging device 1. The DSP circuit 1002 outputs image data obtained by processing the signal from the imaging device 1. The frame memory 1003 temporarily holds the image data processed by the DSP circuit 1002 on a frame-by-frame basis.

[0112] The display unit 1004 is, for example, a panel-type display device such as a liquid crystal panel or an organic EL (Electro Luminescence) panel, and records image data of moving images or still images captured by the imaging device 1 in a recording medium such as a semiconductor memory or a hard disk.

[0113] The operation unit 1006 outputs operation signals for various functions of the electronic device 1000 in accordance with operations by a user. The power supply unit 1007 appropriately supplies various types of power to the DSP circuit 1002, the frame memory 1003, the display unit 1004, the recording unit 1005, and the operation unit 1006 as operating power sources to these power sources.

[0114] <9. Application Examples> (Example of application to moving objects) The technology according to the present disclosure (the present technology) can be applied to various products. For example, the technology according to the present disclosure may be realized as a device mounted on any type of moving body such as an automobile, an electric vehicle, a hybrid electric vehicle, a motorcycle, a bicycle, a personal mobility device, an airplane, a drone, a ship, a robot, etc.

[0115] FIG. 21 is a block diagram showing a schematic configuration example of a vehicle control system, which is an example of a moving object control system to which the technology according to the present disclosure can be applied.

[0116] The vehicle control system 12000 includes a plurality of electronic control units connected via a communication network 12001. In the example shown in Fig. 21, the vehicle control system 12000 includes a drive system control unit 12010, a body system control unit 12020, an outside-vehicle information detection unit 12030, an inside-vehicle information detection unit 12040, and an integrated control unit 12050. Also, as functional configurations of the integrated control unit 12050, a microcomputer 12051, an audio / video output unit 12052, and an in-vehicle network I / F (interface) 12053 are illustrated.

[0117] The drivetrain control unit 12010 controls the operation of devices related to the drivetrain of the vehicle in accordance with various programs. For example, the drivetrain control unit 12010 functions as a control device for a drive force generating device for generating a drive force of the vehicle, such as an internal combustion engine or a drive motor, a drive force transmission mechanism for transmitting the drive force to the wheels, a steering mechanism for adjusting the steering angle of the vehicle, and a braking device for generating a braking force of the vehicle.

[0118] The body system control unit 12020 controls the operation of various devices mounted on the vehicle body according to various programs. For example, the body system control unit 12020 functions as a control device for a keyless entry system, a smart key system, a power window device, or various lamps such as head lamps, back lamps, brake lamps, turn signals, and fog lamps. In this case, radio waves or signals of various switches transmitted from a portable device that replaces a key may be input to the body system control unit 12020. The body system control unit 12020 receives the input of these radio waves or signals and controls the door lock device, power window device, lamps, and the like of the vehicle.

[0119] The outside-vehicle information detection unit 12030 detects information outside the vehicle equipped with the vehicle control system 12000. For example, an imaging unit 12031 is connected to the outside-vehicle information detection unit 12030. The outside-vehicle information detection unit 12030 causes the imaging unit 12031 to capture an image outside the vehicle and receives the captured image. The outside-vehicle information detection unit 12030 may perform object detection processing or distance detection processing for a person, a car, an obstacle, a sign, or characters on a road surface, based on the received image.

[0120] The imaging unit 12031 is an optical sensor that receives light and outputs an electrical signal according to the amount of light received. The imaging unit 12031 can output the electrical signal as an image, or as distance measurement information. The light received by the imaging unit 12031 may be visible light or invisible light such as infrared light.

[0121] The in-vehicle information detection unit 12040 detects information inside the vehicle. For example, a driver state detection unit 12041 that detects the state of the driver is connected to the in-vehicle information detection unit 12040. The driver state detection unit 12041 includes, for example, a camera that captures an image of the driver, and the in-vehicle information detection unit 12040 may calculate the degree of fatigue or concentration of the driver based on the detection information input from the driver state detection unit 12041, or may determine whether the driver is dozing.

[0122] The microcomputer 12051 can calculate control target values ​​for the driving force generating device, the steering mechanism, or the braking device based on the information inside and outside the vehicle acquired by the outside-of-vehicle information detection unit 12030 or the inside-vehicle information detection unit 12040, and output a control command to the drive system control unit 12010. For example, the microcomputer 12051 can perform cooperative control aimed at realizing the functions of an ADAS (Advanced Driver Assistance System), including vehicle collision avoidance or impact mitigation, following driving based on the inter-vehicle distance, vehicle speed maintenance driving, vehicle collision warning, vehicle lane departure warning, etc.

[0123] In addition, the microcomputer 12051 can perform cooperative control for the purpose of autonomous driving, which allows the vehicle to travel autonomously without relying on the driver's operation, by controlling the driving force generating device, steering mechanism, braking device, etc. based on information about the surroundings of the vehicle acquired by the outside vehicle information detection unit 12030 or the inside vehicle information detection unit 12040.

[0124] Furthermore, the microcomputer 12051 can output a control command to the body system control unit 12020 based on the information outside the vehicle acquired by the outside-vehicle information detection unit 12030. For example, the microcomputer 12051 can control the headlamps according to the position of a preceding vehicle or an oncoming vehicle detected by the outside-vehicle information detection unit 12030, and perform cooperative control for the purpose of preventing glare, such as switching from high beams to low beams.

[0125] The audio / video output unit 12052 transmits at least one output signal of audio and video to an output device capable of visually or audibly notifying information to passengers in the vehicle or the outside of the vehicle. In the example of Fig. 21, an audio speaker 12061, a display unit 12062, and an instrument panel 12063 are exemplified as the output device. The display unit 12062 may include at least one of an on-board display and a head-up display, for example.

[0126] FIG. 22 is a diagram showing an example of the installation position of the imaging unit 12031.

[0127] In FIG. 22, a vehicle 12100 has imaging units 12101, 12102, 12103, 12104, and 12105 as an imaging unit 12031.

[0128] The imaging units 12101, 12102, 12103, 12104, and 12105 are provided at positions such as the front nose, side mirrors, rear bumper, back door, and the upper part of the windshield inside the vehicle cabin of the vehicle 12100. The imaging unit 12101 provided at the front nose and the imaging unit 12105 provided at the upper part of the windshield inside the vehicle cabin mainly acquire images of the front of the vehicle 12100. The imaging units 12102 and 12103 provided at the side mirrors mainly acquire images of the sides of the vehicle 12100. The imaging unit 12104 provided at the rear bumper or back door mainly acquires images of the rear of the vehicle 12100. The images of the front acquired by the imaging units 12101 and 12105 are mainly used to detect a preceding vehicle, a pedestrian, an obstacle, a traffic light, a traffic sign, a lane, or the like.

[0129] 22 shows an example of the imaging ranges of the imaging units 12101 to 12104. Imaging range 12111 indicates the imaging range of the imaging unit 12101 provided on the front nose, imaging ranges 12112 and 12113 indicate the imaging ranges of the imaging units 12102 and 12103 provided on the side mirrors, respectively, and imaging range 12114 indicates the imaging range of the imaging unit 12104 provided on the rear bumper or back door. For example, an overhead image of the vehicle 12100 viewed from above is obtained by superimposing the image data captured by the imaging units 12101 to 12104.

[0130] At least one of the imaging units 12101 to 12104 may have a function of acquiring distance information. For example, at least one of the imaging units 12101 to 12104 may be a stereo camera made up of a plurality of imaging elements, or may be an imaging element having pixels for detecting a phase difference.

[0131] For example, the microcomputer 12051 can extract, as a preceding vehicle, a three-dimensional object that is the closest three-dimensional object on the travel path of the vehicle 12100 and travels at a predetermined speed (for example, 0 km / h or more) in approximately the same direction as the vehicle 12100, by calculating the distance to each three-dimensional object in the imaging ranges 12111 to 12114 and the change over time of this distance (relative speed with respect to the vehicle 12100) based on the distance information obtained from the imaging units 12101 to 12104. Furthermore, the microcomputer 12051 can set a vehicle distance to be secured in advance in front of the preceding vehicle, and perform automatic brake control (including follow-up stop control) and automatic acceleration control (including follow-up start control). In this way, cooperative control can be performed for the purpose of automatic driving that travels autonomously without relying on the driver's operation.

[0132] For example, the microcomputer 12051 classifies and extracts three-dimensional object data on three-dimensional objects into two-wheeled vehicles, ordinary vehicles, large vehicles, pedestrians, utility poles, and other three-dimensional objects based on distance information obtained from the imaging units 12101 to 12104, and can use the data for automatic obstacle avoidance. For example, the microcomputer 12051 distinguishes obstacles around the vehicle 12100 into obstacles that are visible to the driver of the vehicle 12100 and obstacles that are difficult to see. Then, the microcomputer 12051 determines a collision risk indicating the risk of collision with each obstacle, and when the collision risk is equal to or greater than a set value and a collision is possible, the microcomputer 12051 can provide driving assistance for collision avoidance by outputting an alarm to the driver via the audio speaker 12061 or the display unit 12062, or by performing forced deceleration or avoidance steering via the drive system control unit 12010.

[0133] At least one of the imaging units 12101 to 12104 may be an infrared camera that detects infrared rays. For example, the microcomputer 12051 can recognize a pedestrian by determining whether or not a pedestrian is present in the captured images of the imaging units 12101 to 12104. The recognition of such a pedestrian is performed, for example, by a procedure of extracting feature points in the captured images of the imaging units 12101 to 12104 as infrared cameras, and a procedure of performing pattern matching processing on a series of feature points that indicate the contour of an object to determine whether or not the object is a pedestrian. When the microcomputer 12051 determines that a pedestrian is present in the captured images of the imaging units 12101 to 12104 and recognizes the pedestrian, the audio / image output unit 12052 controls the display unit 12062 to superimpose a rectangular contour line for emphasis on the recognized pedestrian. The audio / image output unit 12052 may also control the display unit 12062 to display an icon or the like indicating a pedestrian at a desired position.

[0134] An example of a mobile object control system to which the technology according to the present disclosure can be applied has been described above. The technology according to the present disclosure can be applied to, for example, the imaging unit 12031 among the configurations described above. Specifically, for example, the electronic device 300 and the optical element 100 can be applied to the imaging unit 12031. By applying the technology according to the present disclosure to the imaging unit 12031, it is possible to obtain a high-definition captured image. It is possible to perform high-precision control using the captured image in the mobile object control system.

[0135] (Application example to endoscopic surgery system) The technology according to the present disclosure (the present technology) can be applied to various products. For example, the technology according to the present disclosure may be applied to an endoscopic surgery system.

[0136] FIG. 23 is a diagram showing an example of a schematic configuration of an endoscopic surgery system to which the technology according to the present disclosure (the present technology) can be applied.

[0137] 23 shows a state in which an operator (doctor) 11131 is performing surgery on a patient 11132 on a patient bed 11133 using an endoscopic surgery system 11000. As shown in the figure, the endoscopic surgery system 11000 is composed of an endoscope 11100, other surgical tools 11110 such as an insufflation tube 11111 and an energy treatment tool 11112, a support arm device 11120 that supports the endoscope 11100, and a cart 11200 on which various devices for endoscopic surgery are mounted.

[0138] The endoscope 11100 is composed of a lens barrel 11101, a region of a predetermined length from the tip of which is inserted into a body cavity of a patient 11132, and a camera head 11102 connected to the base end of the lens barrel 11101. In the illustrated example, the endoscope 11100 is configured as a so-called rigid scope having a rigid lens barrel 11101, but the endoscope 11100 may be configured as a so-called flexible scope having a flexible lens barrel.

[0139] An opening into which an objective lens is fitted is provided at the tip of the lens barrel 11101. A light source device 11203 is connected to the endoscope 11100, and light generated by the light source device 11203 is guided to the tip of the lens barrel by a light guide extending inside the lens barrel 11101, and is irradiated via the objective lens toward an observation target in the body cavity of the patient 11132. The endoscope 11100 may be a direct-viewing endoscope, an oblique-viewing endoscope, or a side-viewing endoscope.

[0140] An optical system and an image sensor are provided inside the camera head 11102, and reflected light (observation light) from an observation target is collected on the image sensor by the optical system. The observation light is photoelectrically converted by the image sensor to generate an electrical signal corresponding to the observation light, i.e., an image signal corresponding to an observation image. The image signal is transmitted to a camera control unit (CCU) 11201 as RAW data.

[0141] The CCU 11201 is configured with a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), etc., and performs overall control of the operations of the endoscope 11100 and the display device 11202. Furthermore, the CCU 11201 receives an image signal from the camera head 11102, and performs various types of image processing on the image signal, such as development processing (demosaic processing), for displaying an image based on the image signal.

[0142] Under the control of the CCU 11201, the display device 11202 displays an image based on an image signal that has been subjected to image processing by the CCU 11201.

[0143] The light source device 11203 is composed of a light source such as an LED (Light Emitting Diode), and supplies the endoscope 11100 with irradiation light when photographing an operation site or the like.

[0144] The input device 11204 is an input interface for the endoscopic surgery system 11000. A user can input various information and instructions to the endoscopic surgery system 11000 via the input device 11204. For example, the user inputs an instruction to change the imaging conditions (type of irradiated light, magnification, focal length, etc.) of the endoscope 11100.

[0145] The treatment tool control device 11205 controls the driving of the energy treatment tool 11112 for cauterizing tissue, incising, sealing blood vessels, etc. The insufflation device 11206 sends gas into the body cavity of the patient 11132 via the insufflation tube 11111 to inflate the body cavity for the purpose of securing the field of view of the endoscope 11100 and securing the working space of the surgeon. The recorder 11207 is a device capable of recording various information related to the surgery. The printer 11208 is a device capable of printing various information related to the surgery in various formats such as text, image, or graph.

[0146] The light source device 11203 that supplies irradiation light to the endoscope 11100 when photographing the surgical site can be composed of a white light source composed of, for example, an LED, a laser light source, or a combination of these. When the white light source is composed of a combination of RGB laser light sources, the output intensity and output timing of each color (each wavelength) can be controlled with high precision, so that the white balance of the captured image can be adjusted in the light source device 11203. In this case, it is also possible to capture images corresponding to each of the RGB colors in a time-division manner by irradiating the observation object with laser light from each of the RGB laser light sources in a time-division manner and controlling the driving of the image sensor of the camera head 11102 in synchronization with the irradiation timing. According to this method, a color image can be obtained without providing a color filter to the image sensor.

[0147] The light source device 11203 may be controlled to change the intensity of the light it outputs at predetermined time intervals. By controlling the driving of the image sensor of the camera head 11102 in synchronization with the timing of the change in the light intensity to acquire images in a time-division manner and synthesizing the images, it is possible to generate an image with a high dynamic range that is free of so-called blackout and whiteout.

[0148] The light source device 11203 may be configured to supply light of a predetermined wavelength band corresponding to the special light observation. In the special light observation, for example, by utilizing the wavelength dependency of light absorption in body tissue, a narrow band light is irradiated compared to the irradiated light (i.e., white light) during normal observation, and a predetermined tissue such as blood vessels on the mucous membrane surface is photographed with high contrast, so-called narrow band imaging is performed. Alternatively, in the special light observation, a fluorescent observation may be performed in which an image is obtained by fluorescence generated by irradiating an excitation light. In the fluorescent observation, it is possible to irradiate an excitation light to a body tissue and observe the fluorescence from the body tissue (autofluorescence observation), or to locally inject a reagent such as indocyanine green (ICG) into the body tissue and irradiate the body tissue with excitation light corresponding to the fluorescent wavelength of the reagent to obtain a fluorescent image. The light source device 11203 may be configured to supply narrow band light and / or excitation light corresponding to such special light observation.

[0149] FIG. 24 is a block diagram showing an example of the functional configuration of the camera head 11102 and the CCU 11201 shown in FIG.

[0150] The camera head 11102 has a lens unit 11401, an imaging unit 11402, a drive unit 11403, a communication unit 11404, and a camera head control unit 11405. The CCU 11201 has a communication unit 11411, an image processing unit 11412, and a control unit 11413. The camera head 11102 and the CCU 11201 are connected to each other by a transmission cable 11400 so as to be able to communicate with each other.

[0151] The lens unit 11401 is an optical system provided at the connection portion with the lens barrel 11101. Observation light taken in from the tip of the lens barrel 11101 is guided to the camera head 11102 and enters the lens unit 11401. The lens unit 11401 is configured by combining a plurality of lenses including a zoom lens and a focus lens.

[0152] The imaging unit 11402 is composed of an imaging element. The imaging element constituting the imaging unit 11402 may be one (so-called single-plate type) or multiple (so-called multi-plate type). When the imaging unit 11402 is composed of a multi-plate type, for example, each imaging element may generate an image signal corresponding to each of RGB, and a color image may be obtained by combining the image signals. Alternatively, the imaging unit 11402 may be configured to have a pair of imaging elements for acquiring image signals for the right eye and the left eye corresponding to 3D (Dimensional) display. By performing 3D display, the surgeon 11131 can more accurately grasp the depth of the biological tissue in the surgical site. Note that when the imaging unit 11402 is composed of a multi-plate type, multiple lens units 11401 may be provided corresponding to each imaging element.

[0153] Furthermore, the imaging unit 11402 does not necessarily have to be provided in the camera head 11102. For example, the imaging unit 11402 may be provided inside the lens barrel 11101, immediately behind the objective lens.

[0154] The driving unit 11403 is configured by an actuator, and moves the zoom lens and focus lens of the lens unit 11401 by a predetermined distance along the optical axis under the control of the camera head control unit 11405. This allows the magnification and focus of the image captured by the imaging unit 11402 to be appropriately adjusted.

[0155] The communication unit 11404 is configured by a communication device for transmitting and receiving various information to and from the CCU 11201. The communication unit 11404 transmits the image signal obtained from the imaging unit 11402 to the CCU 11201 via the transmission cable 11400 as RAW data.

[0156] Furthermore, the communication unit 11404 receives a control signal for controlling the driving of the camera head 11102 from the CCU 11201, and supplies the control signal to the camera head control unit 11405. The control signal includes information on the imaging conditions, such as information specifying the frame rate of the captured image, information specifying the exposure value at the time of capturing the image, and / or information specifying the magnification and focus of the captured image.

[0157] The image capturing conditions such as the frame rate, exposure value, magnification, and focus may be appropriately specified by a user, or may be automatically set by the control unit 11413 of the CCU 11201 based on an acquired image signal. In the latter case, the endoscope 11100 is equipped with a so-called AE (Auto Exposure) function, AF (Auto Focus) function, and AWB (Auto White Balance) function.

[0158] The camera head control unit 11405 controls the driving of the camera head 11102 based on a control signal received from the CCU 11201 via the communication unit 11404.

[0159] The communication unit 11411 is configured with a communication device for transmitting and receiving various information to and from the camera head 11102. The communication unit 11411 receives an image signal transmitted from the camera head 11102 via the transmission cable 11400.

[0160] Furthermore, the communication unit 11411 transmits, to the camera head 11102, a control signal for controlling the driving of the camera head 11102. The image signal and the control signal can be transmitted by electrical communication, optical communication, or the like.

[0161] The image processing unit 11412 performs various types of image processing on the image signal, which is RAW data sent from the camera head 11102 .

[0162] The control unit 11413 performs various controls related to imaging of the surgical site etc. by the endoscope 11100 and display of the captured image obtained by imaging the surgical site etc. For example, the control unit 11413 generates a control signal for controlling the driving of the camera head 11102.

[0163] Further, the control unit 11413 causes the display device 11202 to display the captured image showing the surgical site, etc., based on the image signal that has been image-processed by the image processing unit 11412. At this time, the control unit 11413 may recognize various objects in the captured image using various image recognition techniques. For example, the control unit 11413 can recognize surgical tools such as forceps, specific living body parts, bleeding, mist when the energy treatment tool 11112 is used, etc., by detecting the shape and color of the edge of an object included in the captured image. When the control unit 11413 causes the display device 11202 to display the captured image, it may use the recognition result to superimpose various types of surgery support information on the image of the surgical site. By superimposing and presenting the surgery support information to the surgeon 11131, the burden on the surgeon 11131 can be reduced and the surgeon 11131 can proceed with the surgery reliably.

[0164] The transmission cable 11400 connecting the camera head 11102 and the CCU 11201 is an electrical signal cable for communication of electrical signals, an optical fiber for optical communication, or a composite cable of these.

[0165] Here, in the illustrated example, communication is performed wired using a transmission cable 11400, but communication between the camera head 11102 and the CCU 11201 may also be performed wirelessly.

[0166] An example of an endoscopic surgery system to which the technology according to the present disclosure can be applied has been described above. Of the configurations described above, the technology according to the present disclosure can be suitably applied to, for example, the lens unit 11401 and the imaging unit 11402. By applying the technology according to the present disclosure, it is possible to provide a high-definition endoscope 11100.

[0167] Although the present disclosure has been described above by way of the embodiment, modifications, application examples, and application examples, the present technology is not limited to the above-described embodiment, etc., and various modifications are possible. For example, although the above-described modifications have been described as modifications of the above-described embodiment, the configurations of the modifications can be appropriately combined.

[0168] The optical element according to an embodiment of the present disclosure includes a first substrate, a plurality of first structures arranged in a first direction on the first substrate, and a medium having a refractive index different from that of the first structures, the medium being arranged to fill the spaces between the plurality of adjacent first structures. The width of the first structures on the side opposite to the first substrate is smaller than the width of the first structures on the first substrate side. This makes it possible to suppress reflection in the optical element. It is possible to realize an optical element capable of improving the light utilization efficiency.

[0169] The optical element according to an embodiment of the present disclosure includes a first substrate, a plurality of first structures each including a first portion having a rectangular side shape provided on the first substrate and a second portion provided on the first substrate below the first portion, a second structure provided on the first structure for each first structure and having a refractive index different from that of the first structure, and a medium provided around the plurality of first structures and the plurality of second structures on the first substrate and having a refractive index different from that of the first structure. This makes it possible to realize an optical element capable of improving the light utilization efficiency.

[0170] In addition, the effects described in this specification are merely examples and are not limited to the description, and other effects may be obtained. In addition, the present disclosure may have the following configurations. (1) A first substrate; A plurality of first structures arranged side by side in a first direction on the first substrate; a medium that is provided so as to fill spaces between adjacent first structures and has a refractive index different from that of the first structures; Equipped with The width of the first structure on the side opposite to the first substrate side is smaller than the width of the first structure on the first substrate side. Optical elements. (2) The width of the first structure in the first direction decreases with increasing distance from the first substrate. The optical element according to (1) above. (3) The first structure has a triangular or trapezoidal side shape. The optical element according to (1) or (2) above. (4) The first structure has a paraboloid shape. The optical element according to (1) or (2) above. (5) The first structure is a first portion provided on the first substrate and having a rectangular side shape; a second portion provided on the first portion; and have The optical element according to (1) or (2) above. (6) The second portion has a width that decreases with distance from the first portion. The optical element according to (5) above. (7) The second portion has a triangular or trapezoidal side shape. The optical element according to (5) or (6) above. (8) The second portion has a parabolic shape. The optical element according to (5) or (6) above. (9) The first structure is a first portion provided on the first substrate; a second portion provided under the first portion in the first substrate; have The optical element according to (1) or (2) above. (10) the first portion has a width that decreases with increasing distance from the first substrate; The second portion has a width that decreases with distance from the first portion. The optical element according to (9) above. (11) The first structure is a first portion provided on the first substrate and having a rectangular side shape; a second portion disposed on the first portion; and a third portion provided under the first portion in the first substrate; and have The optical element according to (1) or (2) above. (12) The third portion has a width that decreases with distance from the first portion. The optical element according to (11) above. (13) The third portion has a triangular or trapezoidal side shape. The optical element according to (11) or (12) above. (14) The second portion has a parabolic shape. The optical element according to (11) or (12) above. (15) a second structure provided between the first substrate and the first structure and having a refractive index different from that of the first structure; The optical element according to any one of (1) to (14) above. (16) The refractive index of the first structure is higher than the refractive index of the medium. The optical element according to any one of (1) to (15) above. (17) The first structure has a size equal to or smaller than the wavelength range of infrared light or equal to or smaller than the wavelength range of visible light. The optical element according to any one of (1) to (16) above. (18) A first substrate; a plurality of first structures each including a first portion having a rectangular side shape provided on the first substrate and a second portion provided on the first substrate below the first portion; a second structure provided on each of the first structures and having a refractive index different from that of the first structures; a medium provided around the first structures and the second structures on the first substrate, the medium having a refractive index different from that of the first structures; An optical element comprising: (19) A first substrate; A plurality of first structures arranged side by side in a first direction on the first substrate; a medium that is provided so as to fill spaces between adjacent first structures and has a refractive index different from that of the first structures; Equipped with The refractive index in the peripheral portion of the first structure is smaller than the refractive index in the central portion of the first structure. Optical elements. (20) An optical element; a photodetector element that receives light incident through the optical element; Equipped with The optical element is A first substrate; A plurality of first structures arranged side by side in a first direction on the first substrate; a medium that is provided so as to fill spaces between adjacent first structures and has a refractive index different from that of the first structures; having The width of the first structure on the side opposite to the first substrate side is smaller than the width of the first structure on the first substrate side. electronic equipment. [Explanation of symbols]

[0171] 10...substrate, 20, 30...structure, 50...protective layer, 100...optical element, 200...optical system, 202...photodetector element, 300...electronic device.

Claims

1. A first substrate; A plurality of first structures arranged side by side in a first direction on the first substrate; a medium that is provided so as to fill spaces between adjacent first structures and has a refractive index different from that of the first structures; Equipped with The width of the first structure on the side opposite to the first substrate side is smaller than the width of the first structure on the first substrate side. Optical elements.

2. The width of the first structure in the first direction decreases with increasing distance from the first substrate. The optical element according to claim 1 .

3. The first structure has a triangular or trapezoidal side shape. The optical element according to claim 1 .

4. The first structure has a paraboloid shape. The optical element according to claim 1 .

5. The first structure is a first portion provided on the first substrate and having a rectangular side shape; a second portion provided on the first portion; and have The optical element according to claim 1 .

6. The second portion has a width that decreases with distance from the first portion. The optical element according to claim 5 .

7. The second portion has a triangular or trapezoidal side shape. The optical element according to claim 5 .

8. The second portion has a parabolic shape. The optical element according to claim 5 .

9. The first structure is a first portion provided on the first substrate; a second portion provided under the first portion in the first substrate; have The optical element according to claim 1 .

10. the first portion has a width that decreases with increasing distance from the first substrate; The second portion has a width that decreases with distance from the first portion. The optical element according to claim 9.

11. The first structure is a first portion provided on the first substrate and having a rectangular side shape; a second portion disposed on the first portion; and a third portion provided under the first portion in the first substrate; and have The optical element according to claim 1 .

12. The third portion has a width that decreases with distance from the first portion. The optical element according to claim 11.

13. The third portion has a triangular or trapezoidal side shape. The optical element according to claim 11.

14. The second portion has a parabolic shape. The optical element according to claim 11.

15. a second structure provided between the first substrate and the first structure and having a refractive index different from that of the first structure; The optical element according to claim 1 .

16. The refractive index of the first structure is higher than the refractive index of the medium. The optical element according to claim 1 .

17. The first structure has a size equal to or smaller than the wavelength range of infrared light or equal to or smaller than the wavelength range of visible light. The optical element according to claim 1 .

18. A first substrate; a plurality of first structures each including a first portion having a rectangular side shape provided on the first substrate and a second portion provided on the first substrate below the first portion; a second structure provided on each of the first structures and having a refractive index different from that of the first structures; a medium provided around the first structures and the second structures on the first substrate, the medium having a refractive index different from that of the first structures; An optical element comprising:

19. A first substrate; A plurality of first structures arranged side by side in a first direction on the first substrate; a medium that is provided so as to fill spaces between adjacent first structures and has a refractive index different from that of the first structures; Equipped with The refractive index in the peripheral portion of the first structure is smaller than the refractive index in the central portion of the first structure. Optical elements.

20. An optical element; a photodetector element that receives light incident through the optical element; Equipped with The optical element is A first substrate; A plurality of first structures arranged side by side in a first direction on the first substrate; a medium that is provided so as to fill spaces between adjacent first structures and has a refractive index different from that of the first structures; having The width of the first structure on the side opposite to the first substrate side is smaller than the width of the first structure on the first substrate side. electronic equipment.

Images