Optical filter and matching composite layer thereof

Abstract

The invention discloses an optical filter and a matched composite layer thereof. The matching composite layer includes a plurality of first refractive layers, a plurality of second refractive layers, and a plurality of third refractive layers. The refractive index of the second refractive layer is larger than that of the first refractive layer and smaller than that of the third refractive layer. One first refraction layer is clamped between the inner sides of any two adjacent second refraction layers, and the outer sides of any two adjacent second refraction layers are clamped between the two third refraction layers, so that a bidirectional progressive increase module is jointly defined. The number of the two-way progressive increase modules contained in the matching composite layer is at least M, and the two-way progressive increase modules are mutually connected and stacked; wherein M is a positive integer, and M is greater than 3. Accordingly, the overall refractive index distribution of the matching composite layer is beneficial for the optical filter to be designed to meet more diverse different requirements.

Description

Technical Field

[0001] The invention relates to a filter, in particular to an optical filter and a matching composite layer thereof. Background Art

[0002] Existing optical filters often use multiple refractive layers stacked in sequence, and the difference between the two refractive indices they have is relatively large. However, the configuration and structure of existing optical filters have gradually failed to meet the different needs of today. Therefore, the inventors believe that the above defects can be improved, and have devoted themselves to research and applied scientific principles, and finally proposed a reasonable design and effective improvement of the above defects of the present invention. Summary of the invention

[0003] The embodiment of the present invention provides an optical filter and a matching composite layer thereof, which can effectively improve the defects that may occur in the existing optical filter.

[0004] The embodiment of the present invention discloses an optical filter, which includes: a substrate; a bonding layer formed on the substrate, and the refractive index of the bonding layer is less than 1.42; and a matching composite layer formed on the bonding layer, and the matching composite layer has N film layers stacked in sequence, wherein N is a positive integer; wherein the N film layers include: a plurality of first refractive layers, each having a first refractive index greater than the refractive index of the bonding layer; a plurality of second refractive layers, each having a second refractive index greater than the first refractive index; and a plurality of third refractive layers, each having a third refractive index greater than the second refractive index; wherein the matching composite layer is connected to the bonding layer with a third refractive layer and is defined as a first film layer; the matching composite layer is connected to the first film layer with a first refractive layer, And defined as a second film layer; the matching composite layer is configured with a first refractive layer at the end away from the bonding layer, and is defined as an Nth film layer; wherein, in the portion of the matching composite layer sandwiched between the second film layer and the Nth film layer, a first refractive layer is sandwiched between the inner sides of any two adjacent second refractive layers, and is sandwiched between two third refractive layers on the outer sides, thereby jointly defined as a bidirectional incremental module; wherein the number of bidirectional incremental modules included in the matching composite layer is at least M and they are stacked and connected to each other; wherein M is a positive integer, and M is greater than 3; wherein the optical filter can be used to form a reflectivity of no more than 10% for an incident light ray that is 60 degrees away from its normal direction and has a wavelength between 400 nanometers and 650 nanometers.

[0005] Optionally, any two adjacent bidirectional incremental modules share a third refractive layer; wherein N is further defined as being between 30 and 80.

[0006] Optionally, any two adjacent two-way increasing modules share a third refractive layer, and each two-way increasing module has a module thickness, and the sum of the module thicknesses of the multiple two-way increasing modules is greater than a total thickness of the matching composite layer.

[0007] Optionally, any two adjacent bidirectional increasing modules share a third refractive layer, and each bidirectional increasing module has a module thickness, and the sum of the module thicknesses of the plurality of bidirectional increasing modules is 105% to 140% of a total thickness of the matching composite layer.

[0008] Optionally, any two adjacent bidirectional increasing modules share a third refraction layer, which has a shared thickness; and each bidirectional increasing module has a module thickness; wherein the sum of the multiple shared thicknesses of the multiple bidirectional increasing modules is 20% to 25% of the sum of the multiple module thicknesses.

[0009] Optionally, a module thickness of each bidirectional incremental module is between 320 nanometers and 380 nanometers.

[0010] Optionally, in each bidirectional increasing module, the thickness of the two second refractive layers is respectively smaller than the thickness of the first refractive layer and also smaller than the thickness of any third refractive layer.

[0011] Optionally, in the plurality of bidirectional increasing modules, a difference between a minimum thickness and a maximum thickness of the first refractive layer is no greater than 15 nanometers.

[0012] Optionally, in each bidirectional incremental module, the thicknesses of the two second refractive layers have a difference of less than 10 nanometers.

[0013] Optionally, in each bidirectional incremental module, the thicknesses of the two third refractive layers have a difference smaller than 15 nanometers.

[0014] Optionally, the refractive index of the bonding layer is between 1.35 and 1.42, the first refractive index is between 1.35 and 1.58, the second refractive index is between 1.62 and 1.93, and the third refractive index is between 2.0 and 2.8.

[0015] The embodiment of the present invention also discloses an optical filter, which includes: a substrate; a bonding layer formed on the substrate; and a matching composite layer formed on the bonding layer, and the matching composite layer has N film layers stacked in sequence, wherein N is a positive integer; wherein the N film layers include: a plurality of first refractive layers, each having a first refractive index greater than the refractive index of the bonding layer; a plurality of second refractive layers, each having a second refractive index greater than the first refractive index; and a plurality of third refractive layers, each having a third refractive index greater than the second refractive index; wherein the matching composite layer is connected to the bonding layer with a third refractive layer and is defined as a first refractive index. a film layer; a matching composite layer connected to the first film layer with a first refractive layer, and defined as a second film layer; the matching composite layer is configured with a film layer at the end away from the bonding layer, and defined as an Nth film layer; wherein, in the portion of the matching composite layer sandwiched between the second film layer and the Nth film layer, a first refractive layer is sandwiched between the inner sides of any two adjacent second refractive layers, and is sandwiched between two third refractive layers on the outer sides, thereby collectively defining a bidirectional incremental module; wherein the number of bidirectional incremental modules included in the matching composite layer is at least M and they are connected and stacked with each other; wherein M is a positive integer, and M is greater than 3.

[0016] Optionally, any two adjacent bidirectional incremental modules share a third refractive layer; wherein N is further defined as being between 30 and 80.

[0017] Optionally, any two adjacent two-way increasing modules share a third refractive layer, and each two-way increasing module has a module thickness, and the sum of the module thicknesses of the multiple two-way increasing modules is greater than a total thickness of the matching composite layer.

[0018] Optionally, in each bidirectional incremental module, the thickness of the two second refractive layers is respectively smaller than the thickness of the first refractive layer and smaller than the thickness of any third refractive layer; wherein, in each bidirectional incremental module, the thickness of the two second refractive layers has a difference of less than 10 nanometers, and the thickness of the two third refractive layers has a difference of less than 15 nanometers.

[0019] Optionally, in the plurality of bidirectional increasing modules, a difference between a minimum thickness and a maximum thickness of the first refractive layer is no greater than 15 nanometers.

[0020] The embodiment of the present invention further discloses a matching composite layer of an optical filter, which includes: N film layers, which are stacked in sequence, and N is a positive integer; wherein the N film layers include: a plurality of first refractive layers, each having a first refractive index; a plurality of second refractive layers, each having a second refractive index greater than the first refractive index; and a plurality of third refractive layers, each having a third refractive index greater than the second refractive index; wherein a third refractive layer located at one end of the matching composite layer is defined as a first film layer; the matching composite layer is connected to the first film layer with a first refractive layer, and is defined as a second film layer; a film layer located at the other end of the matching composite layer is defined as an Nth film layer; wherein, in the portion of the matching composite layer sandwiched between the second film layer and the Nth film layer, a first refractive layer is sandwiched between the inner sides of any two adjacent second refractive layers, and is sandwiched between the outer sides by two third refractive layers, thereby collectively defining a bidirectional incremental module; wherein the number of bidirectional incremental modules included in the matching composite layer is at least M, and they are stacked in a connected manner; wherein M is a positive integer, and M is greater than 3.

[0021] Optionally, any two adjacent bidirectional incremental modules share a third refraction layer; wherein N is further defined as being between 30 and 80.

[0022] Optionally, any two adjacent bidirectional increasing modules share a third refraction layer, which has a shared thickness; and each bidirectional increasing module has a module thickness; wherein the sum of the multiple shared thicknesses of the multiple bidirectional increasing modules is 20% to 25% of the sum of the multiple module thicknesses.

[0023] Optionally, any two adjacent bidirectional incremental modules share a third refractive layer, and each bidirectional incremental module has a module thickness, and the sum of the module thicknesses of multiple bidirectional incremental modules is 105% to 140% of a total thickness of the matching composite layer; wherein the module thickness of each bidirectional incremental module is between 320 nanometers and 380 nanometers.

[0024] In summary, the optical filter and its matching composite layer disclosed in the embodiment of the present invention form M bidirectional increasing modules that are different from the conventional ones stacked one on another, and the refractive index of each bidirectional increasing module can be gradually increased from its first refractive layer toward two opposite directions, so as to adjust the overall refractive index distribution of the matching composite layer, thereby helping the optical filter to be designed to meet more diverse different needs.

[0025] To further understand the features and technical contents of the present invention, please refer to the following detailed description and drawings of the present invention. However, such description and drawings are only used to illustrate the present invention and are not intended to limit the protection scope of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 FIG. 4 is a schematic plan view of an optical filter according to an embodiment of the present invention.

[0027] Figure 2 for Figure 1 Specific configuration diagram.

[0028] Figure 3 for Figure 2 Schematic diagram of simulation test of optical filter at different angles. DETAILED DESCRIPTION

[0029] The following is an explanation of the implementation methods of the "optical filter and its matching composite layer" disclosed in the present invention through specific embodiments. Those skilled in the art can understand the advantages and effects of the present invention from the contents disclosed in this specification. The present invention can be implemented or applied through other different specific embodiments, and the details in this specification can also be modified and changed based on different viewpoints and applications without departing from the concept of the present invention. In addition, the drawings of the present invention are only simple schematic illustrations and are not depicted according to actual dimensions. It is stated in advance. The following implementation methods will further explain the relevant technical contents of the present invention in detail, but the disclosed contents are not intended to limit the scope of protection of the present invention.

[0030] It should be understood that, although the terms "first", "second", "third", etc. may be used herein to describe various components or signals, these components or signals should not be limited by these terms. These terms are mainly used to distinguish one component from another component, or one signal from another signal. In addition, the term "or" used herein may include any one or more combinations of the associated listed items depending on the actual situation.

[0031] See also Figures 1 to 3 As shown, it is an embodiment of the present invention. This embodiment discloses an optical filter 1000, which is preferably in a flat sheet structure. The optical filter 1000 in this embodiment can be suitable for visible light (eg, 420 nanometers to 720 nanometers).

[0032] In this embodiment, the optical filter 1000 includes a substrate 200, a bonding layer 300 formed on the substrate 200, and a matching composite layer 100 formed on the bonding layer 300. The substrate 200 is, for example, a glass substrate, such as a blue glass (blue glass or IR cut glass), and the matching composite layer 100 is bonded to the substrate 200 through the bonding layer 300, but the present invention is not limited thereto. For example, in other embodiments not shown in the present invention, the matching composite layer 100 can be used in conjunction with other components.

[0033] Specifically, the matching composite layer 100 has N film layers 10 stacked in sequence. The N film layers 10 are preferably stacked along the thickness direction H, and the side edges of the N film layers 10 are aligned with each other, and are preferably further aligned with the side edges of the bonding layer 300. Furthermore, N is a positive integer (e.g., N can be limited to between 30 and 80), and N is described as 44 in this embodiment (that is, the plurality of film layers 10 and the bonding layer 300 are described as a total of 45 layers in this embodiment), but the present invention is not limited thereto.

[0034] Further, the N film layers 10 can be divided into a plurality of first refractive layers 10-1, a plurality of second refractive layers 10-2, and a plurality of third refractive layers 10-3 according to the refractive index. Each of the first refractive layers 10-1 has a first refractive index greater than the refractive index of the bonding layer 300. Each of the second refractive layers 10-2 has a second refractive index greater than the first refractive index, and each of the third refractive layers 10-3 has a third refractive index greater than the second refractive index.

[0035] In addition, to facilitate understanding of the overall configuration of the matching composite layer 100, the plurality of film layers 10 may also be described by their stacking order; that is, the matching composite layer 100 is connected to the bonding layer 300 with one third refractive layer 10-3, and is defined as a first film layer 1; the matching composite layer 100 is connected to the first film layer 1 with one first refractive layer 10-1, and is defined as a second film layer 2; the matching composite layer 100 is configured with one film layer 10 at the end away from the bonding layer 300, and is defined as an Nth film layer N. The Nth film layer N is described as the first refractive layer 10-1 in this embodiment, but in other embodiments not shown in the present invention, the Nth film layer N may also be made of other materials (such as the second refractive layer 10-2 or the third refractive layer 10-3) according to actual needs.

[0036] In this embodiment, the refractive index of the bonding layer 300 is less than 1.42 (e.g., between 1.35 and 1.42), the first refractive index may be between 1.35 and 1.58, the second refractive index may be between 1.62 and 1.93, and the third refractive index may be between 2.0 and 2.8. In other words, the optical filter 1000 in this embodiment uses four optical layers with different refractive indices for stacking, thereby providing a more diverse optical configuration and structure.

[0037] It should be additionally explained that, for the convenience of understanding the present embodiment, the bonding layer 300, the first refractive layer 10-1, the second refractive layer 10-2, and the third refractive layer 10-3 are described below using a feasible material as an example, but the present invention is not limited thereto. The bonding layer 300 is, for example, a magnesium fluoride (MgF2) layer, the first refractive layer 10-1 is, for example, a silicon dioxide (SiO2) layer, the second refractive layer 10-2 is, for example, an aluminum oxide (Al2O3) layer, and the third refractive layer 10-3 is, for example, a titanium dioxide (TiO2) layer, but the present invention is not limited thereto. For example, in other embodiments not shown in the present invention, the bonding layer 300 may not be limited to a material having a refractive index less than 1.42, and the bonding layer 300 may be made of other materials (such as: one of the first refractive layer 10-1, the second refractive layer 10-2, and the third refractive layer 10-3) according to actual needs; that is, the first refractive index may also be less than or equal to the refractive index of the bonding layer 300.

[0038] Furthermore, in the portion of the matching composite layer 100 sandwiched between the second film layer 2 and the Nth film layer N, a first refractive layer 10-1 is sandwiched between the inner sides of any two adjacent second refractive layers 10-2, and is sandwiched between two third refractive layers 10-3 on the outer sides, thereby collectively defining a bidirectional incremental module 10a.

[0039] Furthermore, the number of the bidirectional increasing modules 10a included in the matching composite layer 100 is at least M and they are connected and stacked, and the M bidirectional increasing modules 10a connected and stacked in this embodiment are the third film layer 3 to the N-1th film layer N-1 of the matching composite layer 100. Wherein, M is a positive integer greater than 3, and M is illustrated as 10 in this embodiment, but the present invention is not limited thereto. That is, M is illustrated as being greater than N / 5 in this embodiment, but in other embodiments not illustrated in the present invention, M may also be greater than N / 4.

[0040] Accordingly, in any of the two-way increasing modules 10a, any of the second refractive layers 10-2 is sandwiched between one of the first refractive layers 10-1 and one of the third refractive layers 10-3, so that its refractive index can present a gradually increasing distribution.

[0041] As described above, the optical filter 1000 in this embodiment is formed by M bidirectional increasing modules 10a that are different from the conventional ones that are stacked and connected to each other, and the refractive index of each bidirectional increasing module 10a can be gradually increased from its first refractive layer 10-1 toward two opposite directions, so as to adjust the overall refractive index distribution of the matching composite layer 100, thereby helping the optical filter 1000 to be designed to meet more diverse different needs.

[0042] It should be additionally explained that in order for the optical filter 1000 disclosed in this embodiment to have a lower reflectivity when it is rotated to an angle of incidence of 30 to 60 degrees when facing a vertically incident light source (e.g., light with a wavelength between 400 nanometers and 720 nanometers), the matching composite layer 100 preferably meets at least part of the following configuration conditions, but the present invention is not limited thereto.

[0043] In this embodiment, each of the two-way increasing modules 10a has a module thickness T10a, which is preferably between 320 nanometers and 380 nanometers. Further, in this embodiment, the plurality of the two-way increasing modules 10a use different module thicknesses T10a (e.g., 376.49 mm, 364.05 mm, 372.95 mm, 354.67 mm, 332.94 mm, 324.5 mm, 325.44 mm, 326.12 mm, 325.09 mm, and 336.59 mm), but the module thicknesses T10a of any two of the two-way increasing modules 10a can be adjusted to be different or the same according to actual needs, and the present invention is not limited thereto.

[0044] Furthermore, in order to precisely control the optical filter 1000 to achieve a better optical effect within the default thickness, any two adjacent bidirectional increasing modules 10a in this embodiment share a third refractive layer 10-3, which has a shared thickness T10a-1. Further, the sum of the module thicknesses T10a of the plurality of bidirectional increasing modules 10a is greater than a total thickness T100 of the matching composite layer 100. The sum of the shared thicknesses T10a-1 of the plurality of bidirectional increasing modules 10a is 20% to 25% of the sum of the module thicknesses T10a, thereby effectively controlling the total thickness T100 of the matching composite layer 100. In this embodiment, the sum of the module thicknesses T10a of the plurality of bidirectional increasing modules 10a can be controlled to be 105% to 140% of the total thickness T100 of the matching composite layer 100, but the present invention is not limited to the above.

[0045] From another perspective, in order for each of the two-way increasing modules 10a to achieve a better optical effect with its two-way increasing refractive index, each of the two-way increasing modules 10a preferably meets at least part of the following configuration conditions, but the present invention is not limited thereto.

[0046] Specifically, in each of the two-way incremental modules 10a, the thickness of the two second refractive layers 10-2 is less than the thickness of the first refractive layer 10-1 and less than the thickness of any of the third refractive layers 10-3; wherein the thickness of the two second refractive layers 10-2 has a difference of less than 10 nanometers, and the thickness of the two third refractive layers 10-3 has a difference of less than 15 nanometers. In addition, in the plurality of the two-way incremental modules 10a, the difference between the minimum thickness and the maximum thickness of the first refractive layer 10-1 is not greater than 15 nanometers.

[0047] In more detail, the combination layer 300 and the matching composite layer 100 of the optical filter 1000 are formed by Figure 2 The specific configuration shown in the figure is as follows: Figure 3 Results shown.

[0048] According to this, if Figure 3 As shown in the curve A30 of FIG. 1 , the optical filter 1000 can be used to make the incident light with a wavelength between 400 nanometers (nm) and 720 nanometers, which is 30 degrees away from the normal direction, form a reflectivity of no more than 1% (e.g., about 0.69%). Figure 3 As shown in the curve A40 of FIG. 1 , the optical filter 1000 can be used to make the incident light with a wavelength between 400 nanometers and 720 nanometers and an angle of 40 degrees with respect to the normal direction form a reflectivity of no more than 1.5% (e.g., about 1.1%). Figure 3 As shown in the curve A60, the optical filter 1000 can be used to make the incident light with a wavelength between 400 nanometers and 650 nanometers and an angle of 60 degrees from the normal direction form a reflectivity of no more than 10% (e.g., about 7.2%). In addition, Figure 3 Curve A0 represents the reflectivity of the optical filter 1000 and the incident light along its normal direction.

[0049] [Technical Effects of Embodiments of the Invention]

[0050] In summary, the optical filter and its matching composite layer disclosed in the embodiment of the present invention form M bidirectional increasing modules that are different from the conventional ones stacked one on another, and the refractive index of each bidirectional increasing module can be gradually increased from its first refractive layer toward two opposite directions, so as to adjust the overall refractive index distribution of the matching composite layer, thereby helping the optical filter to be designed to meet more diverse different needs.

[0051] The contents disclosed above are only preferred feasible embodiments of the present invention, and are not intended to limit the patent scope of the present invention. Therefore, all equivalent technical changes made using the contents of the present invention's specification and drawings are included in the patent scope of the present invention.

Claims

1. An optical filter, characterized in that: The optical filter comprises: a substrate; a bonding layer formed on the substrate, wherein the refractive index of the bonding layer is less than 1.42; and A matching composite layer is formed on the bonding layer, and the matching composite layer has N film layers stacked in sequence, wherein N is a positive integer; wherein the N film layers include: A plurality of first refractive layers, each having a first refractive index, wherein the first refractive index is greater than the refractive index of the combining layer; a plurality of second refractive layers, each having a second refractive index greater than the first refractive index; and A plurality of third refractive layers, each having a third refractive index greater than the second refractive index; The matching composite layer is connected to the combining layer with the third refractive layer and is defined as a first film layer; the matching composite layer is connected to the first film layer with the first refractive layer and is defined as a second film layer; the matching composite layer is configured with the first refractive layer at the end far away from the combining layer and is defined as an Nth film layer; Among them, in the portion of the matching composite layer sandwiched between the second film layer and the Nth film layer, one first refractive layer is sandwiched between the inner sides of any two adjacent second refractive layers, and two third refractive layers are sandwiched between the outer sides, thereby collectively defining a bidirectional incremental module; The matching composite layer comprises at least M bidirectional increasing modules, which are connected and stacked with each other; wherein M is a positive integer, and M is greater than 3; The optical filter can be used to make an incident light beam with a wavelength between 400 nanometers and 650 nanometers and an angle of 60 degrees with respect to the normal direction thereof form a reflectivity of no more than 10%.

2. The optical filter according to claim 1, characterized in that Any two adjacent bidirectional increasing modules share one third refraction layer; wherein N is further limited to be between 30 and 80.

3. The optical filter according to claim 1, characterized in that Any two adjacent two-way increasing modules share one third refractive layer, and each of the two-way increasing modules has a module thickness, and the sum of the module thicknesses of the multiple two-way increasing modules is greater than a total thickness of the matching composite layer.

4. The optical filter according to claim 1, characterized in that Any two adjacent two-way increasing modules share one third refractive layer, and each of the two-way increasing modules has a module thickness, and the sum of the module thicknesses of the multiple two-way increasing modules is 105% to 140% of the total thickness of the matching composite layer.

5. The optical filter according to claim 1, characterized in that Any two adjacent bidirectional increasing modules share a third refraction layer, and the third refraction layer has a shared thickness; and each bidirectional increasing module has a module thickness; wherein the sum of the multiple shared thicknesses of the multiple bidirectional increasing modules is 20% to 25% of the sum of the multiple module thicknesses.

6. The optical filter according to any one of claims 3 to 5, characterized in that The module thickness of each of the bidirectional increasing modules is between 320 nanometers and 380 nanometers.

7. The optical filter according to claim 1, characterized in that In each of the two-way increasing modules, the thickness of the two second refractive layers is respectively smaller than the thickness of the first refractive layer and also smaller than the thickness of any one of the third refractive layers.

8. The optical filter according to claim 1, characterized in that In the plurality of bidirectional increasing modules, a difference between a minimum thickness and a maximum thickness of the first refractive layer is no greater than 15 nanometers.

9. The optical filter according to claim 1, characterized in that In each of the two-way increasing modules, the thickness of the two second refractive layers has a difference of less than 10 nanometers.

10. The optical filter according to claim 1, characterized in that In each of the two-way increasing modules, the thickness of the two third refractive layers has a difference less than 15 nanometers.

11. The optical filter according to claim 1, characterized in that The refractive index of the bonding layer is between 1.35 and 1.42, the first refractive index is between 1.35 and 1.58, the second refractive index is between 1.62 and 1.93, and the third refractive index is between 2.0 and 2.

8.

12. An optical filter, characterized in that: The optical filter comprises: a substrate; a bonding layer formed on the substrate; and A matching composite layer is formed on the bonding layer, and the matching composite layer has N film layers stacked in sequence, wherein N is a positive integer; wherein the N film layers include: A plurality of first refractive layers, each having a first refractive index, wherein the first refractive index is greater than the refractive index of the combining layer; a plurality of second refractive layers, each having a second refractive index greater than the first refractive index; and A plurality of third refractive layers, each having a third refractive index greater than the second refractive index; The matching composite layer is connected to the combining layer with the third refractive layer and is defined as a first film layer; the matching composite layer is connected to the first film layer with the first refractive layer and is defined as a second film layer; the matching composite layer is configured with the film layer at the end far away from the combining layer and is defined as an Nth film layer; Among them, in the portion of the matching composite layer sandwiched between the second film layer and the Nth film layer, one first refractive layer is sandwiched between the inner sides of any two adjacent second refractive layers, and two third refractive layers are sandwiched between the outer sides, thereby collectively defining a bidirectional incremental module; The matching composite layer includes at least M bidirectional increasing modules, which are connected and stacked with each other; wherein M is a positive integer, and M is greater than 3.

13. The optical filter according to claim 12, characterized in that Any two adjacent bidirectional increasing modules share one third refraction layer; wherein N is further limited to be between 30 and 80.

14. The optical filter according to claim 12, characterized in that Any two adjacent two-way increasing modules share one third refractive layer, and each of the two-way increasing modules has a module thickness, and the sum of the module thicknesses of the multiple two-way increasing modules is greater than a total thickness of the matching composite layer.

15. The optical filter according to claim 12, characterized in that: In each of the bidirectional increasing modules, the thickness of the two second refractive layers is respectively smaller than the thickness of the first refractive layer and also smaller than the thickness of any one of the third refractive layers; wherein, in each of the bidirectional increasing modules, the thickness of the two second refractive layers has a difference of less than 10 nanometers, and the thickness of the two third refractive layers has a difference of less than 15 nanometers.

16. The optical filter according to claim 15, characterized in that In the plurality of bidirectional increasing modules, a difference between a minimum thickness and a maximum thickness of the first refractive layer is no greater than 15 nanometers.

17. A matching composite layer of an optical filter, characterized in that: The matching composite layer of the optical filter comprises: N film layers are stacked in sequence, and N is a positive integer; wherein the N film layers include: A plurality of first refractive layers, each having a first refractive index; a plurality of second refractive layers, each having a second refractive index greater than the first refractive index; and A plurality of third refractive layers, each having a third refractive index greater than the second refractive index; The third refractive layer located at one end of the matching composite layer is defined as a first film layer; the matching composite layer is connected to the first film layer by the first refractive layer and is defined as a second film layer; the film layer located at the other end of the matching composite layer is defined as an Nth film layer; Among them, in the portion of the matching composite layer sandwiched between the second film layer and the Nth film layer, one first refractive layer is sandwiched between the inner sides of any two adjacent second refractive layers, and two third refractive layers are sandwiched between the outer sides, thereby collectively defining a bidirectional incremental module; The matching composite layer includes at least M bidirectional increasing modules, which are connected and stacked with each other; wherein M is a positive integer, and M is greater than 3.

18. The matching composite layer according to claim 17, characterized in that: Any two adjacent bidirectional increasing modules share one third refraction layer; wherein N is further limited to be between 30 and 80.

19. The matching composite layer according to claim 17, characterized in that: Any two adjacent bidirectional increasing modules share a third refraction layer, and the third refraction layer has a shared thickness; and each bidirectional increasing module has a module thickness; wherein the sum of the multiple shared thicknesses of the multiple bidirectional increasing modules is 20% to 25% of the sum of the multiple module thicknesses.

20. The matching composite layer according to claim 19, characterized in that: Any two adjacent bidirectional increasing modules share one third refractive layer, and each of the bidirectional increasing modules has a module thickness, and the sum of the module thicknesses of multiple bidirectional increasing modules is 105% to 140% of the total thickness of the matching composite layer; wherein, the module thickness of each bidirectional increasing module is between 320 nanometers and 380 nanometers.

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