Lens element and electronic device

Abstract

The utility model provides a lens element and an electronic device provided with the lens element. According to one embodiment, a lens element includes: a base layer; a plurality of lenses disposed on the base layer; a lens protection layer which covers the plurality of lenses respectively and is made of a transparent inorganic material; and an overcoat layer covering the lens protection layer, the overcoat layer having a refractive index lower than a refractive index of each of the plurality of lenses.

Description

[0001] Cross-referencing of related applications

[0002] This application claims priority based on Japanese Patent Application No. 2024-043752, filed on March 19, 2024, and references all the contents described in that Japanese Patent Application. Technical Field

[0003] The embodiments of this utility model relate to lens elements and electronic devices. Background Technology

[0004] In recent years, combinations of microlenses with various components have been proposed. As an example of such a combination, the technique of incorporating microlenses into solid-state photoelectric conversion elements to improve the sensitivity of solid-state imaging elements is known. Utility Model Content

[0005] According to one embodiment, the lens element comprises: a base layer; a plurality of lenses disposed on the base layer; a lens protective layer covering the plurality of lenses respectively, formed of a transparent inorganic material; and an outer coating covering the lens protective layer, having a refractive index lower than that of the plurality of lenses.

[0006] According to one embodiment, an electronic device includes: the lens element described above; a substrate; and a light-emitting element disposed between the lens element and the substrate.

[0007] According to one embodiment, the electronic device includes: the lens element described above; a substrate; and a light sensor disposed between the lens element and the substrate.

[0008] According to the embodiments, it is possible to provide lens elements and electronic devices that can achieve the desired optical performance. Attached Figure Description

[0009] Figure 1 This is a schematic plan view of lens element 1 according to the embodiment.

[0010] Figure 2 It is along Figure 1 A schematic cross-sectional view of the lens element 1 of the first embodiment of the VV line.

[0011] Figure 3 It is along Figure 1 A schematic cross-sectional view of the lens element 1 of the second embodiment of the VV line.

[0012] Figure 4 This is a diagram illustrating the manufacturing method of lens element 1.

[0013] Figure 5 This is a diagram illustrating the manufacturing method of lens element 1.

[0014] Figure 6 This is a schematic cross-sectional view of the electronic device 2 according to the third embodiment.

[0015] Figure 7 This is a schematic cross-sectional view of the electronic device 3 according to the fourth embodiment. Detailed Implementation

[0016] One embodiment will be described with reference to the accompanying drawings.

[0017] The disclosure is merely an example, and appropriate modifications that remain consistent with the spirit of the utility model and are readily conceived by those skilled in the art are naturally included within the scope of this utility model. Furthermore, to make the description clearer, the width, thickness, shape, etc., of various parts are sometimes schematically shown in the drawings compared to the actual form, but this is merely an example and does not limit the interpretation of this utility model. Additionally, in this specification and the drawings, the same reference numerals are used for components that perform the same or similar functions as those previously described with respect to existing figures, and repeated detailed descriptions are sometimes appropriately omitted.

[0018] Furthermore, in the accompanying drawings, for ease of understanding, mutually orthogonal X-axis, Y-axis, and Z-axis are shown. The direction along the X-axis is referred to as the first direction X, the direction along the Y-axis as the second direction Y, and the direction along the Z-axis as the third direction Z. Observing various elements parallel to the third direction Z is called planar observation.

[0019] Figure 1 This is a schematic plan view of lens element 1 according to the embodiment.

[0020] The lens element 1 has a base layer 15, multiple lenses LN, a lens protective layer LNP, and an outer coating OC.

[0021] In this embodiment, the shape of the base layer 15 when viewed in a plane is not limited to a rectangle, but can also be a square or other polygons, circles, ellipses or other shapes.

[0022] The substrate 15 is a transparent organic insulating layer, such as formed using resin materials like acrylic resin, epoxy resin, or polyimide resin. Alternatively, the substrate 15 can also be a transparent inorganic insulating layer, a glass substrate, or a resin substrate.

[0023] Multiple lenses LN are arranged at predetermined intervals in the first direction X and the second direction Y. The lenses LN are arranged to overlap with the various elements 10 described later. For example, the layout of the lenses LN corresponds to the layout of the elements 10. The spacing between adjacent lenses LN is equal to the spacing between adjacent elements 10.

[0024] In the illustrated example, the lens LN, when viewed in a plane, has an ellipse with a width a along the first direction X longer than its width b along the second direction Y. However, the shape of the lens LN is not limited to the illustrated example; it can also be an ellipse with width a shorter than width b, or a circle with both width a and width b being the same. The shape of the lens LN can be appropriately varied depending on the shape of the overlapping element 10.

[0025] Lens LN can be formed using various transparent resin materials, such as acrylic resin. From the viewpoint of suppressing undesirable reflection and refraction at the interface between the substrate layer 15 and lens LN, lens LN is preferably formed of a material having the same refractive index as substrate layer 15. Substrate layer 15 can be formed of the same material as lens LN, in which case substrate layer 15 and lens LN can also be formed integrally.

[0026] The lens LN is covered by a lens protective layer LNP, which in turn is covered by an outer coating OC. Use Figure 2 The lens protective layer LNP and the outer coating OC are described in detail.

[0027] Element 10 is covered by substrate layer 15. Element 10 is, for example, a light-emitting element (LD), a light-emitting element (PD), etc. By combining lens element 1 and a light-emitting element (LD) as an example of element 10, an electronic device 2 can be constructed. Furthermore, by combining lens element 1 and a light-emitting element (PD) as an example of element 10, an electronic device 3 can be constructed. Details will be described later.

[0028] [First Implementation Method]

[0029] Figure 2 It is along Figure 1 A schematic cross-sectional view of the lens element 1 of the first embodiment of the VV line.

[0030] Multiple lenses LN are disposed on the substrate 15 and arranged at intervals in the first direction X. Lenses LN are convex lenses. In the illustrated example, lenses LN are aspherical lenses, but they can also be spherical lenses or cylindrical lenses.

[0031] The thickness T1 of the lens LN is not particularly defined. Here, the thickness T1 is equivalent to the length along the third direction Z from the upper surface 15A of the substrate 15 (or the interface between the substrate 15 and the lens LN) to the vertex of the lens LN.

[0032] The lens protective layer LNP covers each of the multiple lenses LN. Figure 2 In the example shown, the lens protective layer LNP individually covers multiple lenses LN, exposing the upper surface 15A of the base layer 15 between adjacent lenses LN.

[0033] The lens protective layer (LNP) is formed of a transparent inorganic material. For example, the lens protective layer (LNP) is formed of silicon nitride, which is a transparent inorganic material.

[0034] The lens protective layer LNP is formed with a substantially uniform thickness. At the apex of the lens LN, the thickness T2 of the lens protective layer LNP is smaller than the thickness T1 of the lens LN, for example, less than 300 nm.

[0035] The outer coating OC overlaps with multiple lens LNs, covering the lens protective layer LNP. Additionally, in Figure 2 In the example shown, the outer coating OC covers the base layer 15 between adjacent lenses LN. In addition, the outer coating OC also functions as a planarization film to flatten the unevenness created by the multiple lenses LN and the lens protective layer LNP.

[0036] The outer coating OC is a transparent organic insulating layer formed from a material with a lower refractive index than the lens LN. For example, the outer coating OC can be formed using resin materials such as acrylic resin, epoxy resin, and polyimide resin.

[0037] Furthermore, the lens LN is formed using a photosensitive resin material. During the formation of the lens LN, if the resin material has low cross-linking properties, and the resin material used to form the outer coating OC is directly applied to the lens LN, the resin material constituting the lens LN will dissolve in the resin material forming the outer coating OC. If the resin material constituting the lens LN dissolves, the lens LN will not be formed into the desired shape, and furthermore, optical performance will be reduced due to changes in refractive index and the generation of haze.

[0038] Therefore, in this embodiment, each lens LN is covered by a lens protective layer LNP formed of a transparent inorganic material (silicon nitride). That is, the lens protective layer LNP is located between the lens LN and the outer coating OC. Therefore, the outer coating OC does not directly contact the lens LN. Therefore, the resin material used to form the outer coating OC does not contact the lens LN, and the dissolution of the lens LN can be suppressed. That is, deformation of the lens LN can be suppressed before and after the process of forming the outer coating OC. As a result, changes in refractive index and the generation of haze can be suppressed, and the desired optical performance can be obtained.

[0039] In particular, silicon nitrides form a dense and uniform structure and exhibit high chemical stability. Therefore, silicon nitrides are preferred as materials for forming the lens protective layer (LNP).

[0040] The thickness T2 of the lens protective layer LNP should be as thin as possible, such as 50 nm or more, to sufficiently suppress the dissolution of the lens LN during the formation of the outer coating OC. However, if the thickness T2 of the lens protective layer LNP exceeds 300 nm, it may lead to a decrease in yield or a reduction in optical properties. Therefore, the thickness of the lens protective layer LNP is preferably 50 nm or more and 300 nm or less.

[0041] In one example, the substrate layer 15, the lens LN, and the lens protective layer LNP have approximately the same refractive index. The outer coating OC has a smaller refractive index than the substrate layer 15, the lens LN, and the lens protective layer LNP.

[0042] As described below, the lens element 1 may have an optical film 16 on the outer coating OC. For example, a polarizing plate can be used as the optical film.

[0043] [Second Implementation]

[0044] Figure 3 It is along Figure 1 A schematic cross-sectional view of the lens element 1 of the second embodiment of the VV line.

[0045] Figure 3 The lens element 1 shown is Figure 2 Compared to the lens element 1 shown, the difference lies in that the lens protective layer LNP covers the base layer 15 between the multiple lenses LN. The outer coating OC is separated from the base layer 15 between adjacent lenses LN. Regarding other structures, [the following is a continuation of the previous sentence, but the translation is incomplete]. Figure 2 The lens element 1 shown is the same, so the description is omitted.

[0046] Figure 3 The second embodiment shown can also obtain the same Figure 2 The first embodiment shown has the same effect. In addition, it eliminates the need for a separate patterning process for the lens protective layer LNP, thus simplifying the manufacturing process.

[0047] Next, refer to Figure 4 and Figure 5 The manufacturing method of lens element 1 will be described.

[0048] First, such as Figure 4 As shown in the upper section, a lens material LNM for forming the lens LN is coated on the substrate layer 15 (first step S1). The lens material LNM is, for example, a negative resin material.

[0049] After the first process S1, as Figure 4 As shown in the middle section, a mask MK with an opening of a predetermined shape is disposed on the lens material LNM. Then, the lens material LNM is exposed to light (e.g., ultraviolet light) L1 through the mask MK (second step S2).

[0050] Next, the second process S2, such as Figure 4 As shown in the lower section, the lens material LNM is developed (third step S3). In the illustrated example, the area of ​​the lens material LNM exposed by light L1 remains, while the area blocked by the mask MK is removed.

[0051] Next, as Figure 5 As shown in the upper section, the remaining lens material LNM is fired, and a convex lens LN is formed by the reflow of the lens material LNM (fourth process S4).

[0052] After the fourth process S4, such as Figure 5 As shown in the middle section, a lens protective layer LNP is formed (fifth step S5). The lens protective layer LNP is formed, for example, by depositing silicon nitride using CVD (Chemical Vapor Deposition). The lens protective layer LNP thus formed uniformly covers the substrate layer 15 and the lens LN. In the illustrated example, after forming the lens protective layer LNP, the lens protective layer LNP is patterned. As a result, the lens protective layer LNP covers the lens LN individually, and the substrate layer 15 is exposed between adjacent lenses LN. Alternatively, the patterning of the lens protective layer LNP can be omitted.

[0053] Next, in the fifth process S5, as follows... Figure 5 As shown in the lower section, the outer coating OC is formed (sixth step S6). The outer coating OC is formed by applying a resin material over the lens protective layer LNP and curing the resin material. At this time, the lens LN is covered by the lens protective layer LNP and therefore does not come into contact with the resin material used to form the outer coating OC. Thus, a lens LN with the desired shape is formed, and a lens element 1 with the desired optical performance is manufactured.

[0054] Next, an electronic device using the lens element 1 described above will be explained.

[0055] [Third Implementation Method]

[0056] Figure 6 This is a schematic cross-sectional view of the electronic device 2 according to the third embodiment.

[0057] The electronic device 2 includes a substrate 11, a circuit layer 12, a spacer 13, a light-emitting element LD, a sealing layer 14, a color filter CF, a lens element 1, and an optical film 16.

[0058] The substrate 11 can be glass or a flexible resin film.

[0059] The circuit layer 12 is disposed on the substrate 11. The circuit layer 12 includes, for example, various circuits such as pixel circuits, various wirings such as scan lines, signal lines, and power lines, as well as various insulating layers.

[0060] Light-emitting elements (LDs) are, for example, organic EL elements, having a lower electrode (LE), an organic layer (OR), and a upper electrode (UE). Furthermore, LDs are not limited to organic EL elements; they can also be other light-emitting elements such as micro-LEDs and mini-LEDs.

[0061] The lower electrode LE is disposed above the circuit layer 12 and is electrically connected to a pixel circuit (not shown). The lower electrode LE is, for example, a multilayer comprising a transparent layer formed of an oxide conductive material such as indium tin oxide (ITO) and a reflective layer formed of a metallic material such as silver.

[0062] The organic layer OR is disposed above the lower electrode LE. The organic layer OR includes a light-emitting layer, as well as various functional layers such as a hole injection layer, a hole transport layer, an electron blocking layer, an electron transport layer, and an electron injection layer.

[0063] The spacer 13 is formed in such a way that it surrounds the lower electrode LE and the organic layer OR. The spacer 13 can be formed of inorganic insulating material or organic insulating material.

[0064] The upper electrode UE is disposed on the organic layer OR and the spacer 13. The upper electrode UE is electrically connected to a power supply line (not shown) and is, for example, set to a common potential. The upper electrode UE is formed, for example, from a metallic material such as an alloy of magnesium and silver (MgAg).

[0065] The sealing layer 14 is configured to cover the upper electrode UE. The sealing layer 14 is formed, for example, as an inorganic insulating layer such as silicon nitride (SiNx), silicon oxide (SiOx), or silicon oxynitride (SiON). In addition to the inorganic insulating layer, the sealing layer 14 may also contain an organic insulating layer.

[0066] The color filter CF is positioned directly above the light-emitting element LD in the third direction Z, and is disposed above the sealing layer 14. Alternatively, the color filter CF can be omitted.

[0067] The lens element 1 described above is formed on top of the color filter CF. In other words, the light-emitting element LD is disposed between the substrate 11 and the lens element 1, and the color filter CF is disposed between the light-emitting element LD and the lens element 1. In the illustrated example, the substrate layer 15 of the lens element 1 covers the color filter CF. The lens LN is disposed directly above the light-emitting element LD and the color filter CF.

[0068] An optical film 16 is disposed on the outer coating OC of the lens element 1. For example, a polarizing plate can be used as the optical film 16. Alternatively, the optical film 16 can be omitted.

[0069] According to this third embodiment, by combining the lens element 1 and the light-emitting element LD, the reflection of light L2 emitted from the light-emitting element LD within the electronic device 2 is suppressed, and the light L2 reaching the substrate layer 15 is extracted by the lens LN, which helps with the display. Therefore, the extraction efficiency of light L2 is improved, power saving is achieved, and the brightness of the front side is increased.

[0070] [Fourth Implementation Method]

[0071] Figure 7 It is along Figure 1 A schematic cross-sectional view of the electronic device 3 of the fourth embodiment of the VV line.

[0072] The electronic device 3 includes a substrate 11, a circuit layer 12, a light sensor PD, a lens element 1, and an optical film 16. Alternatively, the optical film 16 may be omitted.

[0073] The circuit layer 12 is disposed on the substrate 11.

[0074] A light sensor PD is disposed on circuit layer 12. The light sensor PD, for example, has the function of detecting light L3 incident from the upper surface of electronic device 3 and emitting an electrical signal corresponding to the light intensity. The light sensor PD can be, for example, an organic photodiode or an inorganic photodiode.

[0075] The lens element 1 described above is formed on top of the light sensor PD. In other words, the light sensor PD is disposed between the substrate 11 and the lens element 1. In the illustrated example, the base layer 15 of the lens element 1 covers the light sensor PD. The lens LN is disposed directly above the light sensor PD.

[0076] In this embodiment, by combining the optical sensor PD with the lens element 1, the focusing ability of the light L3 incident from the upper surface is improved, thereby enabling the miniaturization of the optical sensor PD.

[0077] As explained above, according to this embodiment, it is possible to provide a lens element and an electronic device that can achieve the desired optical performance.

[0078] Based on the lens element and electronic device described above as embodiments of this utility model, all lens elements and electronic devices that can be appropriately designed and implemented by those skilled in the art also fall within the scope of this utility model as long as they contain the spirit of this utility model.

[0079] Within the scope of this invention, various modifications can be conceived by those skilled in the art, and these modifications should also be understood to fall within the scope of this invention. For example, embodiments obtained by appropriately adding, deleting, or changing the design of the above-described embodiments, or embodiments obtained by adding, omitting, or changing the conditions of processes, are also included within the scope of this invention as long as they possess the spirit of this invention.

[0080] Furthermore, any other effects resulting from the methods described in the above embodiments, as clearly indicated by the description in this specification, or as that can be reasonably conceived by those skilled in the art, should of course be understood as being brought about by this invention.

Claims

1. A lens element characterized by comprising: a base layer; a plurality of lenses disposed on the base layer; a lens protective layer covering the plurality of lenses, respectively, formed of a transparent inorganic material; and an overcoat layer covering the lens protective layer, having a refractive index lower than a respective refractive index of the plurality of lenses.

2. The lens element according to claim 1, characterized in that the overcoat layer has a refractive index lower than the lens protective layer.

3. The lens element according to claim 1, characterized in that the inorganic material is silicon nitride.

4. The lens element according to claim 1, characterized in that the base layer is a transparent organic insulating layer, the overcoat layer has a refractive index lower than the base layer.

5. The lens element according to claim 1, characterized in that the lens protective layer covers the base layer between the plurality of lenses.

6. The lens element according to claim 1, characterized in that the overcoat layer covers the base layer between the plurality of lenses.

7. The lens element according to claim 1, characterized in that a thickness of the lens protective layer is smaller than a respective thickness of the plurality of lenses.

8. The lens element according to claim 1, characterized in that the lens protective layer has a thickness of 50 nm or more and 300 nm or less.

9. The lens element according to claim 1, characterized in that the base layer and the plurality of lenses have the same refractive index.

10. The lens element according to claim 1, characterized in that the base layer and the plurality of lenses are formed of the same material.

11. The lens element according to claim 1, characterized in that the plurality of lenses and the lens protective layer have the same refractive index.

12. An electronic device characterized by comprising: the lens element according to claim 1, a substrate, and a light emitting element disposed between the lens element and the substrate.

13. The electronic device according to claim 12, characterized by further comprising: a color filter between the lens element and the light emitting element.

14. The electronic device according to claim 13, characterized in that the base layer covers the color filter.

15. The electronic device according to claim 12, characterized by further comprising: an optical film on the overcoat layer.

16. The electronic device according to claim 15, characterized in that the optical film is a polarizing plate.

17. An electronic device characterized by comprising: the lens element according to claim 1, a substrate, and a light sensor disposed between the lens element and the substrate.

18. The electronic device according to claim 17, characterized in that the base layer covers the light sensor.

19. The electronic device according to claim 17, characterized by further comprising: an optical film on the overcoat layer.

20. The electronic device according to claim 19, characterized in that the optical film is a polarizing plate.

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