Optical element, optical system device, and method for manufacturing optical system device

Abstract

The invention provides an optical element which can be easily packaged with other components, an optical system device using the optical element, and a method for manufacturing the optical system device. A concave-convex shape (20) having an optical function is provided on a boundary surface (11) between a first dielectric layer (1) having a first refractive index and a second dielectric layer (2) having a second refractive index higher than the first refractive index. The optical element is characterized in that an adjusting part (7) which is separated from the concave-convex shape (20) by a fixed distance is formed on the first dielectric layer (1) side relative to the concave-convex shape (20).

Description

Technical Field

[0001] The present invention relates to an optical element, an optical system device and a method for manufacturing the optical system device. Background Art

[0002] Three-dimensional measurement sensors using the time-of-flight (TOF) method are used in mobile devices, cars, robots, etc. This sensor measures the distance of an object based on the time from when the light irradiated from a light source to the object is reflected back. As long as the light from the light source evenly illuminates a specified area of ​​the object, the distance at each illuminated point can be measured, and the three-dimensional structure of the object can be sensed.

[0003] The sensor system includes: an irradiation unit that irradiates light; an optical element that controls the light of the irradiation unit to a predetermined light distribution; a camera unit that senses light reflected from each point of the object; and a computing unit that calculates the distance of the object based on the signal received by the camera unit. The irradiation unit, the camera unit, or the computing unit can use an existing VCSEL or CMOS imager, a CPU, etc., so the unique part of the system is the optical element.

[0004] In conventional optical elements, microlens arrays have a periodic structure, so there is a problem that light intensity is uneven due to the influence of diffraction. Therefore, in order to suppress this unevenness, a method such as randomly arranging each lens is considered (for example, Patent Document 1).

[0005] On the other hand, TOF has the need for long-distance measurement, and the intensity of the irradiated light needs to be as strong as possible for long-distance measurement. However, the randomly configured microlens array has a high uniformity of irradiated light, which makes the light intensity low, so it is not suitable for long-distance measurement.

[0006] Therefore, as a method capable of saving power and processing a strong optical signal, an optical element that irradiates a dot pattern is used, and three-dimensional measurement based on the flight time of the light is also studied (for example, Patent Document 2).

[0007] Prior art literature

[0008] Patent Literature

[0009] Patent Document 1: Japanese Patent Application No. 2006-500621

[0010] Patent Document 2: WO 2023 / 26987 Summary of the invention

[0011] Here, various studies have been conducted on the portion that exerts an optical function in conventional optical elements, but sufficient consideration has not been given to packaging and the like when manufacturing an optical system device in combination with an irradiation unit or other components.

[0012] Therefore, the present invention relates to an optical element that can be easily packaged with other components, or an optical system device using the optical element, and a method for manufacturing the optical system device.

[0013] In order to achieve the above-mentioned purpose, the optical element of the present invention is provided with a concave-convex shape that performs an optical function on the boundary surface between a first medium layer having a first refractive index and a second medium layer having a second refractive index higher than the first refractive index, and the optical element is characterized in that an adjustment portion is formed on the side of the first medium layer relative to the concave-convex shape to be separated from the concave-convex shape by a fixed distance.

[0014] Here, it is more preferable that the first medium layer is a gas, and the second medium layer and the adjustment portion are integrally formed using a second resin having a second refractive index.

[0015] In addition, it is more preferable that the second dielectric layer is formed of a second resin having a second refractive index, and the first dielectric layer and the adjustment portion are integrally formed of a first resin having a first refractive index.

[0016] Furthermore, it is more preferable that the surface of the first dielectric layer or the second dielectric layer opposite to the boundary surface is flat or curved.

[0017] Furthermore, it is more preferable that an antireflection film is provided on the surface of the first dielectric layer or the second dielectric layer opposite to the boundary surface.

[0018] Furthermore, it is more preferable that a fine concavo-convex structure functioning as a moth-eye is formed on a surface of the first dielectric layer or the second dielectric layer opposite to the boundary surface.

[0019] Furthermore, a third dielectric layer may be provided on a surface of the second dielectric layer opposite to the boundary surface.

[0020] In addition, the third dielectric layer may be formed of the same material as that of the first dielectric layer.

[0021] In addition, it is more preferred that the first dielectric layer is formed on a substrate.

[0022] Furthermore, one or more functional layers having specific functions may be provided on the surface of the substrate opposite to the surface on which the first dielectric layer is located.

[0023] In addition, the functional layer may be a perforated mask.

[0024] Furthermore, the functional layer may be a metal wiring.

[0025] In addition, the functional layer may include: a metal wiring formed on the substrate; an insulating layer formed on the metal wiring; a hole cover formed on the insulating layer and made of metal; and a conductive portion electrically connecting the metal wiring and the hole cover.

[0026] Furthermore, the concavo-convex shape may be a shape in which lenses are periodically arranged.

[0027] In addition, it is an optical element that can diffuse incident light into a specified diffusion range, and more preferably, the diffusion range is defined as the inside of a single closed curve in a specified plane, and the concave-convex shape includes a plurality of peaks and valleys that are not periodic. When the wavelength of the light is set to λ, the refractive index of the first medium layer is set to n1, and the refractive index of the second medium layer is set to n2, the concave-convex shape does not have a portion where the gradient of the concave-convex shape changes by 135 degrees within a range of width λ / (n2-n1), and in the concave-convex shape, the area with such a gradient that causes the incident light to be emitted to an area outside the diffusion range according to Snell's law is less than 5% of the entire area.

[0028] In addition, it is more preferable that the concavo-convex shape is such that the light distribution calculated according to Snell's law is from the center of the diffusion range toward the boundary and cos -n θ is formed in a proportional manner, where 1≤n≤7.

[0029] In addition, the optical system device of the present invention is characterized in that it includes: the above-mentioned optical element of the present invention; and an irradiation unit, which is arranged on the first medium layer side of the optical element and has a light source for irradiating light to the optical element, and the optical element and the irradiation unit are stacked via the adjustment unit.

[0030] Here, the irradiation unit may include a light source cover layer, and the light source cover layer is formed of resin and covers the light source.

[0031] In addition, a cover portion may be provided, and the cover portion contains the optical element and the irradiation portion. In this case, at least a part of the cover portion may be formed of a material having light-shielding properties.

[0032] In addition, it is more preferred that the concavoconvex shape is a shape formed by periodically arranging lenses that transmit light of a wavelength λ, the irradiation unit has a light source that irradiates the plurality of lenses with light of a wavelength λ, and the distance L1 between the irradiation unit and the first focal plane of the lens and the distance L2 between the irradiation unit and the second focal plane satisfy the following equations 1 and 2:

[0033]

[0034] Among them, m and n are natural numbers greater than 1, f1 is the focal length determined by the cross-sectional shape of the lens perpendicular to the y direction, f2 is the focal length determined by the cross-sectional shape of the lens perpendicular to the x direction, P1 is the size of the spacing of the lenses in the x direction, and P2 is the size of the spacing of the lenses in the y direction, which is set to P2.

[0035] In addition, the manufacturing method of the optical system device of the present invention is characterized in that it includes: a stacking process of stacking the above-mentioned optical element of the present invention and an irradiation part arranged on the first medium layer side of the optical element and having a light source for irradiating light to the optical element via the adjustment part; and a cover part forming process of forming a cover part containing the optical element and the irradiation part.

[0036] In addition, another method for manufacturing an optical system device of the present invention is characterized in that it includes: a first resin supplying process of supplying a first resin having photocurability and a first refractive index to a substrate on which an irradiation portion is fixed; a concave-convex shape forming process of forming a concave-convex shape on the surface of the first resin by an imprinting method; and a second dielectric layer forming process of supplying a second resin having photocurability and a second refractive index higher than the first refractive index to the surface of the concave-convex shape and curing the second resin to form a second dielectric layer.

[0037] Effects of the Invention

[0038] The optical element of the present invention is formed with an adjustment portion for keeping a fixed distance from the concavo-convex shape of the optical element, and thus can be easily packaged with an irradiation portion or other components. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 It is a schematic cross-sectional view showing an optical system element of the present invention.

[0040] Figure 2 It is a schematic cross-sectional view showing another optical system element of the present invention.

[0041] Figure 3 This is a schematic cross-sectional view showing still another optical system element of the present invention.

[0042] Figure 4 It is a schematic plan view showing the functional layers of the optical system element of the present invention.

[0043] Figure 5 (a) is a schematic cross-sectional view showing a conventional optical system device, and (b) is a schematic cross-sectional view showing an optical system device of the present invention.

[0044] Figure 6(a) is a schematic cross-sectional view showing an optical system element of the present invention having a plurality of functional layers, and (b) is a plan view showing an optical system element of the present invention having a plurality of functional layers.

[0045] Figure 7 It is a schematic perspective view showing the optical element of the present invention.

[0046] Figure 8 It is an enlarged cross-sectional view showing the optical element of the present invention.

[0047] Fig. 9 It is a diagram for explaining the refraction of the optical element of the present invention.

[0048] Fig.10 It is a schematic plan view showing the optical system device of the present invention.

[0049] Fig.11 It means that the light intensity distribution P(θ) is proportional to cos -n θ (n is 1 to 7) is proportional to [P(θ)∝cos -n θ] is a graph of the light intensity in the camera unit.

[0050] Fig.12 This is a schematic cross-sectional view showing an optical system device in which the optical element of the present invention and an irradiation unit are integrated.

[0051] Fig.13 It is a schematic cross-sectional view showing the optical system device of the present invention.

[0052] Fig.14 It is a schematic cross-sectional view showing the optical system device of the present invention in which a cover portion is formed.

[0053] Fig.15 This is a diagram for explaining an example of an optical system device of the present invention.

[0054] Fig.16 It is a schematic plan view showing the positional relationship between the irradiation unit and the optical element according to the present invention.

[0055] Fig.17 It is a schematic cross-sectional view showing a method for manufacturing the optical system device of the present invention.

[0056] Fig.18 This is a schematic cross-sectional view showing another method of manufacturing an optical system device according to the present invention.

[0057] Fig.19 This is a schematic cross-sectional view showing a method for manufacturing still another optical system device according to the present invention.

[0058] Description of Reference Numerals

[0059] 1First dielectric layer

[0060] 2 Second dielectric layer

[0061] 3Third dielectric layer

[0062] 4A, 4B intermediate dielectric layer

[0063] 5. Substrate

[0064] 6 Functional Layers

[0065] 7. Adjustment Department

[0066] 8 irradiation part

[0067] 11 Boundary surface

[0068] 19First Resin

[0069] 20 Concave and convex shapes

[0070] 29 Second resin

[0071] 61 hole cover

[0072] 62 Metal wiring

[0073] 63 Insulation layer

[0074] 64 conduction unit

[0075] 80 light sources

[0076] 85 Irradiation side dielectric layer

[0077] 150 hood DETAILED DESCRIPTION

[0078] The optical element of the present invention is described below. Figure 1 , Figure 2 As shown, a concavo-convex shape 20 that exerts an optical function is provided on a boundary surface 11 between a first dielectric layer 1 having a first refractive index and a second dielectric layer 2 having a second refractive index higher than the first refractive index.

[0079] In addition, the optical element of the present invention is provided with an adjustment portion 7 for being spaced a fixed distance from the concavo-convex shape 20 on the side of the first dielectric layer 1 relative to the concavo-convex shape 20 (boundary surface 11). Here, the fixed distance refers to the distance in the vertical direction or the horizontal direction that needs to be spaced between the concavo-convex shape 20 and the irradiation part or other components when combined with the irradiation part or other components. In particular, it is preferred that the vertical distance is at least a distance that exceeds the height of the convex part of the concavo-convex shape 20 on the side of the first dielectric layer 1. Since the adjustment portion 7 is formed, it is easy and accurate to perform vertical or horizontal alignment when combined with the irradiation part or other components, so it is easy to package when manufacturing the optical system device. It is more preferred that the adjustment portion 7 is formed integrally with the first dielectric layer 1 or the second dielectric layer 2.

[0080] The difference between the first refractive index and the second refractive index can be any value as long as it can at least enable the concavo-convex shape 20 to perform an optical function. In order to increase the output angle of the lens, it is better to increase the refractive index difference between the first refractive index and the second refractive index, for example, it can be set to 1.8 or more, preferably 1.9 or more, and more preferably 2.0 or more.

[0081] like Figure 1 As shown, in this case, in order to increase the refractive index difference, it is more preferable that the first dielectric layer 1 is a gas. As the gas, any gas can be used, and air or an inert gas can be used. In addition, the gas also includes a gas in a reduced pressure state called a vacuum. In addition, the second dielectric layer 2 can be made of a material that can transmit at least light of a specified wavelength λ, for example, a resin such as a silicone resin, an epoxy resin, or an acrylic resin (hereinafter referred to as the second resin) can be used.

[0082] In addition, if Figure 1 As shown, in this case, the adjustment portion 7 is formed at the periphery of the second dielectric layer 2 at a fixed distance from the concavo-convex shape 20 as the lower part of the side member 25 that determines the thickness (spatial thickness) of the first dielectric layer 1. The material of the side member 25 can be any material. In addition, the second dielectric layer and the adjustment portion 7 can also be formed integrally with a material having a second refractive index (e.g., a second resin).

[0083] Such an optical element can be manufactured in any manner, for example, by using an imprinting method. Specifically, it can be manufactured by forming the concave-convex shape 20 on the material of the second dielectric layer using a mold having a pattern obtained by inverting the concave-convex shape 20 and the adjustment portion 7. In this case, it is also possible to form the concave-convex shape 20 and the adjustment portion 7 in multiple regions, and then divide each region to manufacture multiple optical elements.

[0084] In addition, there are also situations in which, for example, an optical element wants to narrow the light emitted from a lens. In order to narrow the output angle of the lens, for example, it is possible to consider reducing the sag of the lens. However, there are limits to processing accuracy, and it is difficult to make the sag of the lens smaller than a specific size. In such a case, the refractive index difference between the first refractive index and the second refractive index can also be reduced. Thus, for example, in the case where the concave-convex shape 20 is a lens shape, the irradiation angle of the lens can be reduced while the sag of the lens is kept relatively large. The refractive index difference can be, for example, less than 0.4, preferably less than 0.2. Thus, the irradiation angle of the lens can be less than 30 degrees while the sag of the lens is kept above 10 μm.

[0085] In this case, the first dielectric layer 1 and the second dielectric layer 2 may be made of materials with a small refractive index difference. The material of the first dielectric layer 1 or the second dielectric layer 2 may be any material as long as it can at least transmit light of a specified wavelength λ, for example, a silicone resin, an epoxy resin, or an acrylic resin may be used.

[0086] In addition, in this case, if Figure 2 As shown, adjustment portion 7 can directly utilize surface 12 of first dielectric layer 1 opposite to boundary surface 11. That is, the thickness of first dielectric layer 1 can be set to a size that is spaced a certain distance from concavo-convex shape 20 on the first dielectric layer 1 side relative to concavo-convex shape 20.

[0087] Such an optical element can be manufactured in any manner, for example, by using an imprinting method. Specifically, a mold having a pattern obtained by inverting the concavo-convex shape 20 and the adjustment portion 7 can be used to manufacture the optical element by coating the material of the second dielectric layer after the material of the first dielectric layer forms the concavo-convex shape 20, or by coating the material of the first dielectric layer after the material of the second dielectric layer forms the concavo-convex shape 20. In this case, the concavo-convex shape 20 is a large area or forms a plurality of regions, and then a plurality of optical elements can be manufactured by dividing it.

[0088] In addition, the surface 21 of the second dielectric layer 2 opposite to the boundary surface 11 can be formed as follows: Figure 1 (a) or Figure 2 In addition, the surface 21 can also be formed as shown in (a). Figure 1 (b), (c) or Figure 2The curved surface shown in (b) and (c) of FIG. Here, the plane or curved surface means that there is no concave-convex shape larger than the wavelength of the emitted light, but it is sufficiently smooth. By setting it to a plane or a curved surface, it is easy to add layers, films or shapes with various functions to the surface 21. For example, an anti-reflection film can be formed on the surface 21. Thereby, the reflection of light when it is emitted from the second dielectric layer 2 can be suppressed. In addition, in order to suppress reflection, the surface 21 can also be formed with a fine concave-convex structure that functions as a moth eye. The fine concave-convex structure is formed to be smaller than the wavelength of the light passing through.

[0089] In addition, there is a case where the surface 21 on the second dielectric layer 2 side is desired to be protected in order to improve the environmental performance such as the high temperature and high humidity characteristics or the high temperature-low temperature thermal cycle characteristics of the first dielectric layer 1 or the second dielectric layer 2. In this case, the surface 21 on the second dielectric layer 2 side may be protected as shown in FIG. Figure 1 (d) Figure 2 As shown in (d), the third dielectric layer 3 is provided on the surface 21. For example, when a wide-angle lens is to be manufactured, a resin with a high refractive index is required for the second dielectric layer 2. However, in most cases, the environmental performance of the resin with a high refractive index is low. Therefore, as long as the third dielectric layer 3 that can relieve the stress of the second dielectric layer 2 is configured on the surface of the second dielectric layer 2, the environmental performance of the optical element can be improved.

[0090] The material of the third dielectric layer 3 can be any material as long as it can improve the environmental performance of the first dielectric layer 1 or the second dielectric layer 2, for example, silicone resin, epoxy resin or acrylic resin can be used. In addition, the third dielectric layer 3 is preferably formed of the same material as the first dielectric layer 1.

[0091] In addition, if Figure 3 As shown in FIG. 1 , the first dielectric layer 1 may also be formed on the substrate 5. Thus, one or more functional layers 6 having specific functions can be formed on the surface 52 of the substrate 5 opposite to the surface 51 on which the first dielectric layer 1 is located. In this case, the lower surface of the functional layer 6 can be separated from the concavo-convex shape 20 by a fixed distance, and the lower surface of the functional layer 6 becomes the adjustment portion 7. As the substrate 5, for example, a glass substrate can be used. In addition, as shown in FIG. Figure 3 As shown in (c), an intermediate resin layer 4A may be formed on the surface 51 of the substrate 5. The intermediate resin layer 4A may be, for example, a resin layer as a base that improves the adhesion between the substrate 5 and the second dielectric layer 2. In addition, the first dielectric layer 1 is formed on the substrate 5. Figure 3 The case where the first dielectric layer 1 is in direct contact with the surface 51 of the substrate 5 as shown in (a) to (c) also includes the case where the first dielectric layer 1 is in direct contact with the surface 51 of the substrate 5. Figure 3(d) shows a case where one or more intermediate resin layers 4B are sandwiched between the substrate 5. The intermediate resin layer 4B is, for example, a resin layer serving as a base to improve adhesion between the substrate 5 and the first dielectric layer 1.

[0092] As the functional layer 6, any structure may be used as long as it has a specific function, for example, Figure 4 The puncture mask 61 shown in (a) of FIG. 6A has an opening 61a for shielding a part of light. Thus, it is possible to prevent electromagnetic waves as noise from being emitted from outside the opening 61a. As the puncture mask 61, for example, a metal such as gold can be used.

[0093] In addition, as another functional layer 6, for example Figure 4 The metal wiring 62 shown in (b) of FIG. The metal wiring 62 constitutes a predetermined circuit, etc. Figure 5 As shown in (a), metal wiring 62 is formed on the lower surface 52 of the substrate 5, and the resin layer 2A on the surface thereof is formed with a concave-convex shape 20 such as a lens. In this case, the metal wiring 62 is insulated by the resin layer 2A, so in order to conduct with the package side, it is necessary to form a separate structure for conduction. On the other hand, Figure 5 As shown in (b), the optical element of the present invention forms a concave-convex shape 20 such as a lens on one side of the substrate 5, and forms a metal wiring 62 on the other side of the surface 52, so that the metal terminal of the metal wiring 62 can be exposed to the surface. Therefore, there is no need for a structure for conducting with the packaging side such as the irradiation part 8, and it can be directly connected to the contact point on the packaging side. As the metal wiring 62, for example, ITO can be used.

[0094] In addition, the functional layer 6 may also be a combination of layers having specific functions. Figure 6 As shown in (a), the functional layer includes: a metal wiring 62 such as ITO, which is formed on the surface 52 of the substrate 5; an insulating layer 63, which is formed on the metal wiring 62; a hole cover 61, which is formed of metal and formed on the insulating layer 63; and a conductive portion 64, which electrically connects the metal wiring 62 and the hole cover 61. As a result, the optical element can be given a function of eye safety or EMI. In addition, by forming the hole cover 61 with metal, it is possible to easily connect the contact point on the package side with the metal wiring 62.

[0095] The concave-convex shape 20 of the optical element can be any structure as long as it has an optical function. For example, it can be a shape that can control the incident light and emit it, such as a microlens array (MLA) or a diffractive optical element (DOE). The lenses of the microlens array can be arranged periodically or randomly.

[0096] As an example of the concavo-convex shape 20, Figure 7The optical element 100 shown in FIG. 1 is capable of diffusing incident light to a predetermined diffusion range 91. The diffusion range 91 of the optical element 100 is defined as the interior of a single closed curve in a predetermined plane. Figure 8 As shown, the concavo-convex shape 20 includes a plurality of peaks and valleys without periodicity.

[0097] Here, the diffusion range 91 is defined as the interior of a single closed curve 92 such as a polygon or an ellipse in a predetermined plane 90. In addition, the predetermined plane 90 mentioned here refers to a plane (xy plane) perpendicular to the optical axis (z axis) of the light source irradiating the optical element, and is a plane at least 100 times larger than the size of the light when emitted by the light source 2 and away from the optical element.

[0098] The concavo-convex shape 20 is formed so that the incident light is refracted into the diffusion range 91 according to Snell's law. Fig. 9 Here, for the sake of simplicity, the following optical element is considered: the exit surface 21 is a plane (xy plane), and the incident surface 18 has a concave-convex shape 20 defined by z=f(x, y). In addition, here, light in a direction perpendicular to the xy plane (z-axis direction) is incident on the incident surface.

[0099] First, the incident angle θ1 of the light relative to the incident surface 22 of the optical element and the refraction angle θ2 of the refracted light in the optical element satisfy the relationship n1sinθ1=n2sinθ2 according to Snell's law. Similarly, the incident angle θ3 relative to the exit surface 21 of the optical element and the refraction angle θ4 of the exit light emitted to the outside also follow Snell's law. Therefore, when the refractive index of the first medium layer 1 of the optical element is n1, the refractive index of the second medium layer 2 is n2, and the refractive index of air is n3, n1sinθ1=n2sinθ2 and n2sinθ3=n3sinθ4 hold. In addition, as Fig. 9 As shown, θ3 = θ1-θ2. That is, the exit angle θ4 can be calculated according to Snell's law between the incident surface 22 and the exit surface 21 of the optical element, and can be expressed as θ4 = g(θ1). For example, when the incident angle θ1 is small enough and can be approximated as n1θ1 = n2θ2, n2θ3 = n3θ4, it can be expressed as θ4 = θ1(n2-n1) / n3.

[0100] Thus, the light distribution of the emitted light, that is, the intensity distribution at the emission angle θ4, and the frequency distribution at the incident angle θ1 become in a one-to-one relationship. Fig. 9 As shown, since the incident angle θ1 is the same as the inclination angle θ1 (gradient) of the concavoconvex surface of the optical element (the surface of the concavoconvex shape 20), the frequency distribution of the incident angle θ1 corresponds to the frequency distribution of the inclination angle θ1 of the concavoconvex surface of the optical element.

[0101] In addition, the partial derivatives of z with respect to x and y are Respectively, when using y=y o 、x=x o Therefore, when light is incident vertically on the incident surface of the optical element, y=y o The incident angle of the surface is set to θ ix 、x=x o The incident angle on the surface is set to θ iy When Therefore, it can be used express.

[0102] On the other hand, when y=y of the light emitted from the optical element o The exit angle of the surface is set to θ ox 、x=x o The angle of incidence on the surface is set to θ oy When the incident angle θ ix With the exit angle θ ox Between, incident angle θ iy With the exit angle θ oy Snell's law is satisfied between them, so we can use θ ox =g(θ ix ),θ oy =g(θ iy )express.

[0103] In addition, if θ is used o The frequency function FREQUENCY(θ) of the emitted light is h(θ o ) is h(θ o )=FREQUENCY(θ o ). Therefore, if these relationships are combined, the light intensity distribution h(θ ox )for:

[0104] Similarly, the light intensity distribution h(θ oy )for:

[0105] Based on the above description, in order to achieve a predetermined light intensity distribution, it is necessary to calculate the frequency distribution of the inclination angle θ1 (gradient) of the surface of the optical element to design the concavo-convex shape 20. At this time, the concavo-convex shape 20 should be designed so that the area having such a gradient that the incident light is emitted to the area outside the diffusion range 91 when calculated according to Snell's law is less than 5% of the entire area, preferably less than 3%, and more preferably less than 1%.

[0106] Furthermore, in order to make the optical element function as a diffuser, when the wavelength of light incident on the optical element in a vacuum is set to λ, the refractive index of the first dielectric layer 1 is set to n1, and the refractive index of the second dielectric layer 2 is set to n2, the concavo-convex shape 20 has a height of at least 2.5 times λ / (n2-n1), preferably 5 times or more, and more preferably 10 times or more. In addition, the height of the concavo-convex shape 20 mentioned here refers to the difference between the highest peak and the lowest valley of the concavo-convex shape 20.

[0107] In addition, if there is a part where the inclination angle θ1 (gradient) changes sharply on the surface of the concavo-convex shape 20, it will be affected by scattering or diffraction, etc., so it is not preferred. Therefore, it is preferred that the inclination angle θ1 of the concavo-convex shape 20 changes slowly. Specifically, the concavo-convex shape 20 is formed so that its surface does not have a part where the inclination angle θ1 (gradient) changes by 135 degrees, preferably formed so that its surface does not have a part where the inclination angle θ1 (gradient) changes by 120 degrees, and more preferably formed so that its surface does not have a part where the inclination angle θ1 (gradient) changes by 90 degrees. In addition, if the change in the inclination angle θ1 is a change in size that cannot be perceived by light, it can be ignored. Therefore, when the wavelength of the light incident on the optical element in a vacuum is set to λ, the refractive index of the first dielectric layer 1 is set to n1, and the refractive index of the second dielectric layer 2 is set to n2, the inclination angle θ1 of the surface of the concavo-convex shape 20 can be calculated based on the height change over the width λ / (n2-n1) from any position to any position. Here, the width refers to the width in a direction perpendicular to the z-axis direction of the concavo-convex shape 20 (a direction parallel to the incident surface or the emission surface).

[0108] In addition, if Fig.10 As shown, a general sensor system mainly includes: an optical element 100; an irradiation unit 8; a camera unit 300, which senses light reflected from each point of the object 10; and a calculation unit 400, which calculates the distance of the object based on the signal received by the camera unit 300. Here, the light reflected at a wider angle and incident on the camera unit 300 has a lower light intensity. Therefore, in order for the camera to also well perceive the light incident from a wide angle, it is preferred that the distribution of light passing through the optical element 100 is such that the larger the angle θ, the higher the light intensity. That is, it is preferred that the distribution of light in the far field (far-field) of the optical element 100 is such that the larger the angle θ, the higher the intensity. Therefore, it is preferred that at least the concave-convex shape 20 is formed so that the light distribution calculated according to Snell's law increases monotonically from the center of the diffusion range 91 toward the boundary. Therefore, the concave-convex shape 20 of the optical element can be designed so that the frequency distribution of the inclination increases monotonically as the inclination increases.

[0109] In this specification, the center of the diffusion range 91 refers to the position of the intersection of the optical axis of the light source 2 and the diffusion range 91 when the light of the light source 2 is irradiated perpendicularly to the optical element of the present invention. In addition, the boundary of the diffusion range 91 refers to the position of the maximum peak in the light intensity distribution on the cross section at the portion corresponding to the closed curve 92 mentioned above.

[0110] In addition, in an optical system in which light emitted from the optical element 100 is reflected on a screen and then returns to a camera, if the reflection on the screen is Lambertian reflection, in order to make the intensity of the light returning to the camera uniform with respect to the angle θ, it is necessary to make the light intensity distribution P(θ) of the far-field of the optical element 100 and cos -7 θ is proportional to [P(θ)∝cos-7θ]. Therefore, it is most preferable that the light distribution of the light emitted from the light source 2 and transmitted through the optical element 100 is proportional to cos -7 is proportional to θ.

[0111] Fig.11 is the light intensity distribution P(θ) of the far-field of the optical element 100 in the optical system where the light passing through the optical element 100 is reflected on the screen and then returns to the camera and cos -n θ (n is 1 to 7) is proportional to [P(θ)∝cos -n θ], the intensity of the light returned to the camera unit is calculated relative to the incident angle θ. It can be seen that the larger the incident angle, the smaller the light intensity, and the larger the n, the smaller the difference. In addition, it can be seen that if the light intensity distribution P(θ) is compared with cos -7 θ is proportional to [P(θ)∝cos -7 θ], the intensity of the light returning to the camera becomes uniform relative to the angle θ.

[0112] However, when irradiating light at a wide angle, it is difficult to completely match the cos -7 θ, so it is also possible to allow the camera sensitivity to be proportional to cos -n The light intensity distribution is proportional to θ, where 1≤n≤7.

[0113] Therefore, the concavo-convex shape 20 of the optical element can be formed as follows: the light distribution calculated according to Snell's law is from the center of the diffusion range 91 toward the boundary and cos -n θ is proportional to θ, where 1≤n≤7, preferably in proportion to cos -7 Therefore, the frequency distribution of the inclination angle θ1 of the concavo-convex shape 20 of the optical element is in a manner proportional to cos -n θ1 is formed in a manner proportional to 1≤n≤7, preferably in a manner proportional to cos- 7 θ1 is formed in a proportional manner.

[0114] Specifically, each concavoconvex shape 20 has a height of at least 5 times λ / (n2-n1), preferably 10 times λ / (n2-n1), and more preferably 25 times λ / (n2-n1).

[0115] Next, the optical system device of the present invention is described. Figure 5 (b) or Figure 6 (a) Fig.12 , Fig.13 As shown, the optical system device of the present invention comprises: the optical element of the present invention described above; and an irradiation unit 8 disposed on the first dielectric layer 1 side of the optical element to irradiate light to the optical element. The optical element and the irradiation unit 8 are stacked via an adjustment unit 7.

[0116] Here, the irradiation part 8 can be of any structure as long as it has a light source 80 that irradiates light with a wavelength of λ. In addition, the irradiation part 8 can be either a single light source or a plurality of light sources. In addition, it can also be a structure in which a plurality of light sources are formed by passing the light of a single light source through a slit formed with a plurality of fine holes. In the case where the irradiation part 8 includes a plurality of light sources, it is preferred that the light sources 80 are formed on the same plane so that the distance or angle between the optical element and the irradiation part 8 can be adjusted more accurately. As a specific example of the irradiation part 8, there is a VCSEL (Vertical Cavity Surface Emitting LASER) that is expected to generate high output with less power. The VCSEL includes: a single-emitter VCSEL having a light source 80 that can irradiate light in a direction perpendicular to the light-emitting surface, or a multi-emitter VCSEL having a plurality of light sources 80. In addition, a light absorption film is formed on the portion other than the light source 80, which is preferred because it can prevent the entry of noise generated by reflected light.

[0117] In addition, if Fig.12 As shown, it is preferred that the irradiation section 8 is formed integrally with the adjustment section 7 of the optical element of the present invention. Thus, it is possible to provide an optical system device with high reliability in which the distance or angle between the optical element and the irradiation section 8 is adjusted. In particular, in order to exert the optical function of the concavo-convex shape 20 of the optical element, it is sometimes necessary to adjust the position of the optical element relative to the irradiation section 8. In this case, the optical system device can be formed integrally with the irradiation section 8 and the optical element using the adjustment section 7 so that the distance is appropriate.

[0118] Furthermore, in most cases, the irradiation section 8 generates heat when emitting light. If a gas with low thermal conductivity exists between the optical element and the irradiation section 8 as in the past, the performance of the irradiation section 8 or the optical element may be reduced or damaged. Fig.13 As shown in the figure, there is a light source cover layer 85, which is formed of resin and covers the light source 80. The thermal conductivity of the resin is higher than that of the gas, so the heat dissipation of the light source can be improved. In addition, the refractive index difference between the resin and the material of the light source 80 can be made smaller than that of the gas, so the light extraction efficiency of the light source 80 can be improved. Moreover, the light source 80 is covered by the light source cover layer 85, so even if the optical system device is damaged, the possibility of the light source 80 being exposed is low, which is also preferred from the perspective of human eye safety. In addition, an anti-reflection film or a fine concavo-convex structure that functions as a moth eye can be formed on the surface of the light source cover layer 85. In this way, the reflection of light when it is emitted from the light source cover layer 85 can be suppressed. As the resin constituting the light source cover layer 85, any resin can be used as long as it can at least transmit light with a wavelength of λ and can play the optical function of the concavo-convex shape 20. For example, a silicone resin, an epoxy resin, or an acrylic resin can be used. In addition, a resin as a base that can improve the adhesion between the irradiation part 8 and the material of the first dielectric layer 1 or the second dielectric layer 2 can also be used. In addition, the surface of the light source cover layer 85 may include a base material such as glass or a metal layer.

[0119] In addition, it is preferred that the light source cover layer 85 is formed to have a thickness that is a constant distance from the light source 80 to the surface 86 of the light source cover layer 85. Thus, when combined with an optical element or other components, vertical or horizontal alignment can be easily and accurately performed, so that packaging is easy when manufacturing an optical system device. Fig.13 As shown in (a) and (b), by making the adjustment portion 7 of the optical element abut against the surface 86 of the light source covering layer 85 and forming them as one, a highly reliable optical system device can be provided in which the distance or angle between the optical element and the irradiation portion 8 is adjusted.

[0120] In addition, the first dielectric layer 1 can also be used together with the light source cover layer 85. In this case, Fig.13 As shown in (c), the space between the concavo-convex shape 20 can be filled with the material of the first dielectric layer 1 and formed integrally with the optical element. In this case, the boundary between the first dielectric layer 1 and the irradiation part 7 becomes the adjustment part 7.

[0121] In addition, if Fig.14As shown, the optical system device of the present invention may also include a cover 150 containing an optical element and an irradiation unit 8. The light source 80 is contained in the cover 150, so that even if the optical system device is damaged, the possibility of the light source 80 being exposed is low, which is also preferred from the perspective of eye safety. The resin constituting the cover 150 can be any resin as long as it can at least transmit light of a wavelength λ and can exert the optical function of the concavo-convex shape 20. For example, a silicone resin, an epoxy resin, or an acrylic resin can be used. In addition, when the first dielectric layer 1 is a gas, the above-mentioned side member 25 is formed at the periphery of the second dielectric layer 2 in such a way that the gas as the first dielectric layer 1 can be sealed between the irradiation unit 8 and the second dielectric layer.

[0122] In addition, when a resin with a high refractive index is used in the second dielectric layer, titanium oxide (TiO2) is sometimes used as the resin. However, titanium oxide acts as a photocatalyst, so there are problems such as the resin being decomposed when irradiated with ultraviolet light, etc. Therefore, in this case, the material constituting at least a part of the cover 150 or the material covering the cover 150 can use a light-shielding material that can inhibit the transmission of ultraviolet light, etc.

[0123] In addition, the cover 150 may be integrally formed of the same material, or may be formed of different materials for each portion such as the upper surface and the side surfaces. For example, the side surfaces may be formed of a light-shielding material, and the upper surface may be formed of a material that transmits only infrared rays.

[0124] Next, as an example of the optical system device of the present invention, an optical system device for irradiating a dot pattern will be described. Fig.15 As shown, the optical element used in the optical system device is an optical element having a concave-convex shape 20 obtained by periodically arranging lenses 21 that transmit light of wavelength λ on the boundary surface 11 of a first medium layer 1 having a first refractive index and a second medium layer 2 having a second refractive index higher than the first refractive index. In addition, Fig.15 (a) is an optical system device when the first dielectric layer 1 is a gas and the second dielectric layer is a resin, Fig.15 (b) is an example of an optical system device in which both the first dielectric layer 1 and the second dielectric layer are made of resin.

[0125] In addition, the lens 21 has a focal point at a position on the first dielectric layer 1 side and at a predetermined distance f (f>0) from the lens 21. The optical element of the present invention can improve the contrast as the focal distance f is 10 μm or more, 20 μm or more, 40 μm or more, or 60 μm or more, that is, as the focal distance f increases. In addition, the position of the plane perpendicular to the optical axis of the lens including the focal point of the lens 21 is referred to as the focal position 25 of the optical element.

[0126] The shape of the lens 21 can be freely designed according to the diffusion pattern of the points to be irradiated (hereinafter referred to as the dot pattern). For example, if the dot pattern is to be circular, the shape of the lens 21 can be a spherical lens. In addition, if the dot pattern is to be non-circular, the shape of the lens 21 can be an appropriately designed aspherical lens. In the case of an aspherical lens, the focal length varies depending on the direction. Fig.15 (c) is an example of an aspheric lens in which the focal distance determined by the cross-sectional shape of the lens perpendicular to the y direction is f1, the focal distance determined by the cross-sectional shape of the lens perpendicular to the x direction is f2 (f1≠f2), the size of the spacing of the lenses in the x direction is P1, and the size of the spacing of the lenses in the y direction is P2. In addition, the lens shape can use a convex lens or a concave lens. In the case of a convex lens, it is preferred that the convex lens portion faces the irradiation unit 8 side.

[0127] In addition, if Fig.16 As shown in FIG. 1 , the periodic arrangement of the lenses 21 is such that the lenses 21 that are square or rectangular when viewed from above are arranged in a square shape, or the lenses 21 that are hexagonal when viewed from above are arranged in a hexagonal shape, etc. In addition, the lenses 21 may be any lenses as long as they function as lenses, for example, Fresnel lenses, DOE lenses, or super lenses, etc. In addition, an anti-reflection film may be formed on the lenses 21, and the anti-reflection film may prevent the light from the irradiation unit 8 from being reflected.

[0128] The irradiation section 8 has a light source 80 that irradiates light with a wavelength of λ toward the plurality of lenses 21. The irradiation section 8 may be a single light source or a plurality of light sources. In the case where one irradiation section 8 includes a plurality of light sources 80, it is preferred that the light sources 80 are formed on the same plane. In addition, in the case where one irradiation section 8 includes a plurality of light sources 80, it is necessary to configure them in such a manner that even if the light sources 80 and the optical element are relatively moved in parallel, the number of light sources 80 relative to the lenses 21 of the optical element is the same when viewed from above. Therefore, in the case where the positions of the light sources 80 relative to the lenses 21 are converged on one lens in an overlapping manner, it can be formed in such a manner that the apparent positions of the converged light sources 80 coincide with each other. For example, the light sources included in the same irradiation section can be configured in such a manner that they are periodically arranged, and the pitch P in the x-direction of the light sources is 1 / 4 of the width of the light source 80. x is a natural number multiple or a reciprocal multiple of the lens pitch P1, and the pitch P in the y direction y is a natural number multiple or a reciprocal multiple of the pitch P2 of the lenses. In other words, the light sources 80 included in the same irradiation unit 8 are regularly arranged as follows: when the pitch in the x direction is set to P x , the size of the spacing in the y direction is set to P y When , j, and k are set to natural numbers greater than 1, P x=jP1 or jP x =P1, and satisfies P y = kP2 or kP y =P2. Fig.16 In (a) and (b), the spacing P of the light sources 80 is x , P y The pitches P1 and P2 of the lens 21 of the optical element 2 are equal. Fig.14 In (c), the spacing P of the light sources 80 is x , P y is 1 / 2 of the pitch P1, P2 of the lens 21 of the optical element 2. Fig.14 In (d), the spacing P of the light sources 80 is x , P y It is twice the pitches P1 and P2 of the lenses 21 of the optical element 2 .

[0129] The irradiation unit 8 and the optical element 2 are arranged so that the optical axis direction of the light source 80 of the irradiation unit 8 coincides with the optical axis direction of the lens 21 of the optical element 2 .

[0130] (Positional Relationship between Illumination Section and Optical Element)

[0131] like Fig.15 As shown, the distance L1 between the irradiation unit 8 and the first focal plane 251 of the lens 21 and the distance L2 between the irradiation unit 8 and the second focal plane 252 can convert the incident light into a dot pattern with a large contrast when the following formulas α and β are satisfied. Here, m and n are natural numbers greater than 1, P1 is the size of the spacing of the lenses 21 in the x direction, P2 is the size of the spacing in the y direction, λ is the wavelength of the light incident from the irradiation unit 8, f1 is the focal distance determined by the cross-sectional shape of the lens 21 perpendicular to the y direction, f2 is the focal distance determined by the cross-sectional shape of the lens 21 perpendicular to the x direction, and a, b, c, d are coefficients representing the allowable errors. In addition, the first focal plane 251 refers to a plane perpendicular to the optical axis (z direction) of the lens 21 and located at a focal position determined by the cross-sectional shape of the lens 21 perpendicular to the y direction. In addition, the second focal plane 252 refers to a plane perpendicular to the optical axis (z direction) of the lens 21 and located at a focal position determined by the cross-sectional shape of the lens 21 perpendicular to the x direction. In addition, when the focal points are located on both sides of the lens 21, it is preferred that the first focal plane 251 and the second focal plane 252 are based on the focal point located on the irradiation portion 8 side of the lens 21. In addition, the distances L1 and L2 refer to the distances (optical path lengths) traveled in a vacuum in the same time as when the light travels in the medium, and when the refractive index of the medium is N and the actual distance is L, they are expressed by their product NL.

[0132] (Mathematical formula 1)

[0133]

[0134] (Mathematical formula 2)

[0135]

[0136] Here, the values ​​of coefficients a, b, c, d of formula α and formula β are 1, 0.5, 0.3, and 0.1, and the smaller the coefficients, the better. When the coefficients of formula α and formula β are a=b=c=d=1, formula α and formula β are respectively expressed as the following formula 1 and formula 2.

[0137] (Mathematical formula 3)

[0138]

[0139] (Mathematical formula 4)

[0140]

[0141] In addition, the distances L1 and L2 can maximize light intensification when the following equations 3 and 4 are satisfied in the case where a=b=c=d=0.

[0142] (Mathematical formula 5)

[0143]

[0144] (Mathematical formula 6)

[0145]

[0146] In addition, the adjustment portion 7 of the optical element of the present invention is preferably formed so that the concavo-convex shape 20 and the illumination portion are separated by the predetermined distance in consideration of Expressions 1 and 2, preferably Expressions 3 and 4.

[0147] In addition, it is difficult to produce diffraction when the spacing P1 and P2 is too small compared to the wavelength λ of the light from the light source 80. Therefore, as long as enough lenses 21 are included in the light distribution angle of the light source 80 to produce diffraction, the spacing P1 and P2 can be large enough compared to the wavelength λ of the light from the light source 80, for example, more than 5 times, preferably more than 10 times.

[0148] In addition, the above-mentioned optical element for irradiating a dot pattern can be used not only for irradiating a dot pattern but also for diffuser purposes. When the optical element 2 is used for diffuser purposes, the irradiation unit 8 and the optical element can be arranged or integrated to form an optical system device in such a manner that the distances L1 and L2 between the irradiation unit 8 and the focal position 25 of the optical element do not satisfy at least equations 1 and 2.

[0149] (Manufacturing method of optical system device)

[0150] Next, the manufacturing method of the optical system device of the present invention is described. Fig.17 As shown in (a), the irradiation unit 8 and the optical element are prepared and appropriately aligned. Fig.17 As shown in (b), the adjustment part 25 is bonded to the irradiation part 8 by contacting it. In this case, as long as the height of the adjustment part 25 is appropriately formed in advance, the z-direction alignment can be performed only by contacting the adjustment part 25. In addition, the optical system device can also form the irradiation part 8 and the optical element in groups, but it can also be as follows Fig.17 As shown in FIG. 1 , an optical element component having a plurality of optical elements integrally formed therein and an irradiation component having a plurality of irradiation units 8 integrally formed therein are stacked together. In this case, after the optical element component and the irradiation component are stacked and bonded, as shown in FIG. Fig.17 The optical system is cut as shown in (c) and divided according to each optical system device.

[0151] In addition, when the cover portion 150 including the optical element and the irradiation portion 8 is formed, for example Fig.18 As shown in (a), first, the optical system device is arranged on the substrate. Fig.18 As shown in (b), a fluid cover 150 material is supplied to the optical system device to cover it, and after solidification, the cover 150 is formed. In addition, when the first dielectric layer 1 is a gas, the side member 25 is formed at the periphery of the second dielectric layer 2 in such a way that the gas of the first dielectric layer 1 can be sealed between the irradiation unit 8 and the second dielectric layer. In this way, the space of the first dielectric layer 1 can be protected from the entry of the cover 150 material therein.

[0152] In addition, the cover part 150 can also be formed for each optical system device, but it can also be formed as follows. Fig.18 As shown in FIG. 1 , the cover 150 is formed on a plurality of optical system devices at once. In this case, after the cover 150 is formed, Fig.18 It is cut as shown in (c) and divided into each optical system device.

[0153] In addition, another method of manufacturing an optical system device of the present invention will be described in which the first dielectric layer 1 is used in common with the light source cover layer 85. This manufacturing method includes a first resin supplying step, a concavo-convex shape forming step, and a second dielectric layer forming step.

[0154] In the first resin supplying step, the material of the first dielectric layer 1 is supplied onto the substrate to which the irradiation unit is fixed. For example, a first resin 19 having a photocurable property and a first refractive index is supplied. Fig.19As shown in (a) and (b) of FIG. 1 , the irradiation part 8 such as the VCSEL is fixed to the substrate 55 such as the lead frame by chip bonding, and is electrically connected by wire bonding, thereby preparing the substrate 55 to which the irradiation part 8 is fixed. Next, as shown in FIG. Fig.19 As shown in (c), the first resin 19 having photocurability can be supplied to the irradiation section 8 side of the substrate 55.

[0155] In the concavo-convex shape forming step, the concavo-convex shape 20 is formed on the surface of the first resin 19 by an imprint method. Fig.19 As shown in (d), a mold 50 having a pattern 20A identical to the concavo-convex shape 20 is pressed against the first resin 19 to form the concavo-convex shape 20 on the first resin 19. Fig.19 As shown in (e), the first resin 19 is cured and the mold 50 is removed, thereby forming a first dielectric layer 1 having a first refractive index.

[0156] In the second dielectric layer forming step, a material of the second dielectric layer having a second refractive index higher than the first refractive index is supplied to the surface of the concavo-convex shape 20 to form the second dielectric layer 2. Specifically, Fig.19 As shown in (f), a second photocurable resin 29 is applied to the surface 21 of the concavo-convex shape 20. Fig.19 As shown in (g), the second resin 29 is cured to form the second dielectric layer 2 having a second refractive index higher than the first refractive index.

[0157] The optical system device thus formed can be manufactured by appropriately dividing it into Fig.15 The optical system device shown in (h).

Claims

1. An optical element, wherein a concavo-convex shape having an optical function is provided on a boundary surface between a first medium layer having a first refractive index and a second medium layer having a second refractive index higher than the first refractive index, wherein: An adjustment portion is formed on the first dielectric layer side relative to the concavo-convex shape to be spaced a fixed distance from the concavo-convex shape.

2. The optical element according to claim 1, characterized in that: The first dielectric layer is a gas, The second medium layer and the adjustment portion are integrally formed by using a second resin having a second refractive index.

3. The optical element according to claim 1, characterized in that: The second dielectric layer is formed by using a second resin having a second refractive index. The first medium layer and the adjustment portion are integrally formed by using a first resin having a first refractive index.

4. The optical element according to any one of claims 1 to 3, characterized in that: A surface of the first dielectric layer or the second dielectric layer opposite to the boundary surface is planar or curved.

5. The optical element according to any one of claims 1 to 3, characterized in that: An antireflection film is provided on a surface of the first dielectric layer or the second dielectric layer opposite to the boundary surface.

6. The optical element according to any one of claims 1 to 3, characterized in that: A fine concavo-convex structure functioning as a moth-eye is formed on a surface of the first dielectric layer or the second dielectric layer opposite to the boundary surface.

7. The optical element according to claim 1, characterized in that: The second dielectric layer has a third dielectric layer on a surface opposite to the boundary surface.

8. The optical element according to claim 5, characterized in that: The third dielectric layer is formed of the same material as that of the first dielectric layer.

9. The optical element according to claim 1, characterized in that: The first dielectric layer is formed on a substrate.

10. The optical element according to claim 7, characterized in that: One or more functional layers having specific functions are provided on a surface of the substrate opposite to the surface on which the first dielectric layer is located.

11. The optical element according to claim 8, characterized in that: The functional layer is an escutcheon.

12. The optical element according to claim 8, characterized in that: The functional layer is a metal wiring.

13. The optical element according to claim 8, characterized in that: The functional layer includes: a metal wiring formed on the substrate; an insulating layer formed on the metal wiring; an aperture mask formed on the insulating layer and made of metal; and a conductive portion electrically connecting the metal wiring and the aperture mask.

14. The optical element according to claim 1, characterized in that: The concavoconvex shape is a shape in which lenses are periodically arranged.

15. The optical element according to claim 1, characterized in that: The optical element is capable of diffusing incident light into a predetermined diffusion range. The diffusion range is defined as the interior of a single closed curve in a specified plane, The concavoconvex shape includes a plurality of peaks and valleys without periodicity, When the wavelength of the light is λ, the refractive index of the first medium layer is n1, and the refractive index of the second medium layer is n2, the concavo-convex shape does not have a portion where the gradient of the concavo-convex shape changes by 135 degrees within a range of a width of λ / (n2-n1), In the above-mentioned concavo-convex shape, the area having such a gradient that the incident light is emitted to the area outside the above-mentioned diffusion range according to Snell's law accounts for 5% or less of the entire area.

16. The optical element according to claim 13, characterized in that: The concave-convex shape is a light distribution calculated according to Snell's law from the center of the diffusion range toward the boundary and cos -n θ is formed in a proportional manner, where 1≤n≤7.

17. An optical system device, characterized in that: include: The optical element according to any one of claims 1 to 3; as well as an irradiation unit, which is arranged on the first medium layer side of the optical element and has a light source for irradiating light to the optical element, The optical element and the irradiation section are stacked via the adjustment section.

18. The optical system device according to claim 17, characterized in that: The irradiation unit includes a light source covering layer, which is formed of resin and covers the light source.

19. The optical system device according to claim 17, characterized in that: A cover portion is provided, and the cover portion contains the optical element and the irradiation portion.

20. The optical system device according to claim 19, characterized in that: At least a portion of the cover is formed of a material having a light-shielding property.

21. The optical system device according to claim 17, characterized in that: The concavoconvex shape is a shape formed by periodically arranging lenses that transmit light having a wavelength of λ. The irradiation unit includes a light source for irradiating light having a wavelength of λ toward the plurality of lenses. The distance L1 between the irradiation portion and the first focal plane of the lens and the distance L2 between the irradiation portion and the second focal plane satisfy the following equations 1 and 2: Among them, m and n are natural numbers greater than 1, f1 is the focal length determined by the cross-sectional shape of the lens perpendicular to the y direction, f2 is the focal length determined by the cross-sectional shape of the lens perpendicular to the x direction, P1 is the size of the spacing of the lenses in the x direction, and P2 is the size of the spacing of the lenses in the y direction.

22. A method for manufacturing an optical system device, characterized in that: include: a laminating step of laminating the optical element according to any one of claims 1 to 3 and an irradiation unit disposed on the first dielectric layer side of the optical element and having a light source for irradiating light to the optical element via the adjustment unit; as well as The cover portion forming step forms a cover portion that contains the optical element and the irradiation portion.

23. A method for manufacturing an optical system device, characterized in that: include: A first resin supplying step of supplying a first resin having photocurability and a first refractive index onto the substrate to which the irradiation portion is fixed; a concavo-convex shape forming step of forming a concavo-convex shape on the surface of the first resin by an embossing method; as well as The second dielectric layer forming step is to supply a second resin having photocurability and a second refractive index higher than the first refractive index to the surface of the concavo-convex shape and to cure the second resin to form a second dielectric layer.

Images