Optical components and optical lenses

Abstract

The present application discloses an optical element and an optical lens. The optical element according to the embodiment of the present application includes: a body; and a black film coated on the body. The black film can be formed by stacking an absorption film layer, a spacing film layer and a refractive film layer in a certain order, wherein the refractive index of the spacing film layer is less than or equal to the refractive index of the refractive film layer. The film layer closest to the body can be the absorption film layer, and the film layer farthest from the body can be the spacing film layer, and the absorption film layer and the refractive film layer are not adjacent to each other.

Description

Technical Field

[0001] The present application relates to the field of optical elements, and more specifically, to an optical element coated with a black film and an optical lens including the optical element. Background Art

[0002] Optical lenses are used to image the subject onto the imaging surface, such as the optical lens of a mobile phone that images on the sensor, and telescopes that can be used to observe the image with the naked eye. The lens determines the quality of the imaging performance, so lens performance has become an important consideration in the design of devices such as cameras, and in recent years, portable electronic devices such as mobile phones have increasingly higher requirements for lenses.

[0003] An optical lens usually includes optical elements such as a plastic lens barrel, an optical lens group, a light shielding sheet, and a spacer ring. The optical lens group is disposed in the plastic lens barrel. The optical lens group includes lenses, and the lenses are interlocked with each other by an interlocking structure or the spacing between the lenses is controlled by a spacer ring to provide an appropriate optical distance or to prevent adjacent lenses from being damaged by friction or collision. A light shielding sheet is disposed between the lenses to shield unnecessary light inside the plastic lens barrel. After light enters the optical lens, it will be reflected at the inner wall of the plastic lens barrel and the surfaces of other components, thereby forming stray light at the imaging surface, which reduces the imaging quality.

[0004] The prior art generally coats the inner wall of the plastic lens barrel and the ineffective area of ​​the lens with black paint to reduce stray light, but the industry expects that the optical element can absorb light more effectively. Summary of the invention

[0005] In order to solve or partially solve the above-mentioned defects in the prior art, an embodiment of the present application proposes an optical element coated with a black film.

[0006] According to an embodiment of the present application, an optical element is provided, comprising: a body; and a black film coated on the body. The black film may be formed by stacking an absorption film layer, a spacing film layer, and a refractive film layer in a certain order, wherein the refractive index of the spacing film layer is less than or equal to the refractive index of the refractive film layer. The film layer closest to the body may be the absorption film layer, and the film layer farthest from the body may be the spacing film layer, and the absorption film layer and the refractive film layer are not adjacent to each other.

[0007] The black film includes: a first film layer, a second film layer and at least two subsequent film layers in sequence along the direction away from the body, wherein the number of layers of at least two subsequent film layers is an even number; the first film layer is an absorption film layer, and the second film layer and the even-numbered layers in at least two subsequent film layers are spacing film layers.

[0008] In one embodiment, when the number of the at least two subsequent film layers is an even number greater than 4, the third film layer disposed adjacent to the second film layer in the at least two subsequent film layers may be an absorption film layer.

[0009] In one embodiment, the material of the absorption film layer may include at least one of chromium, titanium, copper, silver, aluminum and silicon oxide; the material of the spacing film layer may include at least one of oxides, nitrides and oxynitrides of aluminum, titanium, silicon, tin, hafnium, tantalum and yttrium; the material of the refractive film layer may include at least one of titanium oxide, niobium pentoxide, tantalum pentoxide, silicon hydride, hydrogenated silicon germanium and silicon carbide.

[0010] In one embodiment, the material of the spacer film layer may include aluminum oxide and silicon dioxide; and the material of the refractive film layer may include titanium oxide.

[0011] In one embodiment, the thickness of the first film layer is in the range of 80nm to 100nm, and the material of the first film layer includes chromium; the thickness of the second film layer is in the range of 30nm to 50nm, and the material of the second film layer includes aluminum oxide and silicon dioxide; the thickness of the third film layer is in the range of 10nm to 20nm, and the material of the third film layer includes chromium; and at least two subsequent film layers include in sequence along the direction away from the body: a fourth film layer, which is a spacer film layer, the thickness of the fourth film layer is in the range of 20nm to 40nm, and the material of the fourth film layer includes aluminum oxide and silicon dioxide; a fifth film layer, which is a refractive film layer, the thickness of the fifth film layer is in the range of 100nm to 120nm, and the material of the refractive film layer includes titanium pentoxide; a sixth film layer, which is a spacer film layer, the thickness of the sixth film layer is in the range of 80nm to 100nm, and the material of the sixth film layer includes aluminum oxide and silicon dioxide.

[0012] In one embodiment, the thickness ratio of the first film layer, the second film layer, the third film layer, the fourth film layer, the fifth film layer and the sixth film layer is 9:4:1:2:10:8.

[0013] In one embodiment, the refractive index n1 of the absorption film layer may satisfy: 2.0≤n1≤4.0; the refractive index n2 of the spacing film layer may satisfy: 1.4≤n2≤2.0; and the refractive index n3 of the refractive film layer may satisfy: 2.0≤n3≤4.0.

[0014] In one embodiment, the absorption rate Abs of the black film may be greater than 95% for light in the wavelength range of 400 nm to 780 nm.

[0015] In one embodiment, the reflectivity R of the black film may be less than 1% for light in the wavelength range of 400 nm to 780 nm.

[0016] In one embodiment, the transmittance T of the black film may be less than 3% for light in the wavelength range of 400 nm to 780 nm.

[0017] In one embodiment, the main body is a lens barrel, and the black film may be plated on the object side end of the lens barrel.

[0018] In one embodiment, the main body is an optical lens, the optical lens has an effective diameter area and a non-effective diameter area, and the black film is plated on the non-effective diameter area.

[0019] In one embodiment, any one surface or both surfaces of the optical lens are coated with a black film.

[0020] In one embodiment, the absorbent film layer is formed by chemical coating.

[0021] In one embodiment, the black film is formed by local coating.

[0022] In one embodiment, the body is an annular septum, and any one surface or both surfaces of the annular septum are plated with a black film.

[0023] On the other hand, according to an embodiment of the present application, an optical lens is provided, and the optical lens includes the aforementioned optical element.

[0024] The optical element provided in the embodiment of the present application has a black film coated on its body that can be used to absorb light, the spacing film layer is set in the even-numbered layers, and the other film layers can be interspersed in the odd-numbered layers. The outermost layer is set as the spacing film layer to reduce the reflection of the light irradiated on the black film. The spacing film layer and the refractive film layer can reduce the transmittance of light and further reduce the reflectivity. The absorption film layer allows most of the light irradiated into the black film to be absorbed. When the body of the optical element provided in the embodiment of the present application is a transparent substrate, the light transmittance of the area of ​​the transparent substrate coated with the black film is much smaller than that of the area without the black film. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Other features, objects and advantages of the present disclosure will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings:

[0026] Figure 1 shows a schematic structural diagram of an optical element according to an embodiment of the present application;

[0027] Figure 2 shows a reflectivity wavelength curve of a black film according to an embodiment of the present application;

[0028] Figure 3 shows a wavelength curve of the absorbance of the black film according to an embodiment of the present application;

[0029] Figure 4 A schematic structural diagram of an optical lens coated with a black film according to an embodiment of the present application is shown; and

[0030] Figure 5A schematic structural diagram of an optical lens according to an embodiment of the present application is shown. DETAILED DESCRIPTION

[0031] In order to better understand the present application, a more detailed description will be made of various aspects of the present application with reference to the accompanying drawings. It should be understood that these detailed descriptions are only descriptions of exemplary embodiments of the present application, and are not intended to limit the scope of the present application in any way. Throughout the specification, the same reference numerals refer to the same elements. The expression "and / or" includes any and all combinations of one or more of the associated listed items.

[0032] It should be noted that in this specification, the expressions first, second, third, etc. are only used to distinguish one feature from another feature, and do not represent any limitation on the features. Therefore, without departing from the teaching of the present application, the first spacer film layer discussed below may also be referred to as the second spacer film layer. And vice versa.

[0033] In the drawings, the thickness, size and shape of the components have been slightly adjusted for ease of illustration. The drawings are for illustration only and are not strictly drawn to scale. For example, the thickness of the optical lens and the thickness of the black film are not in the ratio in actual production. As used herein, the terms "substantially", "approximately" and similar terms are used as terms of approximation, not as terms of degree, and are intended to illustrate the inherent deviations in measured or calculated values ​​that will be recognized by a person of ordinary skill in the art.

[0034] It should also be understood that the terms "comprises", "including", "having", "includes" and / or "comprising", when used in this specification, indicate the presence of the stated features, elements and / or components, but do not exclude the presence or addition of one or more other features, elements, components and / or combinations thereof. In addition, when expressions such as "at least one of..." appear after a list of listed features, they modify the entire listed features rather than modifying the individual elements in the list. In addition, when describing embodiments of the present application, "may" is used to mean "one or more embodiments of the present application". And, the term "exemplary" is intended to refer to an example or illustration.

[0035] Unless otherwise specified, all words (including engineering terms and scientific and technological terms) used in this article have the same meaning as those commonly understood by ordinary technicians in the field to which this application belongs. It should also be understood that, unless clearly stated in this application, words defined in common dictionaries should be interpreted as having the same meaning as their meaning in the context of the relevant technology, and should not be interpreted in an idealized or overly formal sense.

[0036] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. In addition, unless explicitly limited or contradictory to the context, the specific steps included in the method described in the present application are not necessarily limited to the order described, but can be performed in any order or in parallel. The present application will be described in detail below with reference to the accompanying drawings and in conjunction with the embodiments.

[0037] The optical element according to the embodiment of the present application includes: a body and a black film coated on the body. The black film can be formed by stacking an absorption film layer, a spacing film layer and a refractive film layer in a certain order, wherein the refractive index of the spacing film layer can be less than or equal to the refractive index of the refractive film layer, and the refractive index of the spacing film layer can also be less than or equal to the refractive index of the absorption film layer. In the direction away from the body, the first film layer closest to the body is the absorption film layer, and the film layer farthest from the body is the spacing film layer, and the absorption film layer and the refractive film layer are not adjacent to each other, that is, except for the spacing film layer as the outermost layer, the two sides of the remaining spacing film layers are either the absorption film layer or the refractive film layer, and the spacing film layer as the outermost layer has one side thereof being either the absorption film layer or the refractive film layer.

[0038] In an exemplary embodiment, the total number of film layers in the black film is an even number greater than or equal to 4, and each even-numbered layer is a spacer film layer, C represents an absorption film layer, L represents a spacer film layer, and X represents a film layer not specifically limited, and X can be an absorption film layer or a refractive film layer. The film layers of the black film can be preset to have the following stacking structure: CL-[XL] m , wherein the film layers stacked according to the structure in the brackets are the subsequent film layers, which include at least two film layers and the total number of layers is an even number, m is the number of repetitions of the structure in the brackets, 1≤m, so the total number of film layers in the preset stacking structure is 2m+2. The absorption film layer is the first layer, usually attached to the substrate, the outermost layer is the spacing film layer, usually as a film layer facing the light, the even-numbered layers in the preset stacking structure of the black film are spacing film layers, and the refractive index of the refractive film layer is not less than the refractive index of the spacing film layer.

[0039] The optical element coated with a black film provided in the embodiment of the present application has the even-numbered layers (including the outermost layer) in the black film set as spacer film layers, and the odd-numbered layers are interspersed with refractive film layers or absorption layers, thereby reducing the reflection of light irradiated thereon and absorbing the light irradiated thereon. When the black film is set on an opaque body, the stray light caused by the surface diffuse reflection of the optical element can be reduced. When the black film is set on a transparent body, the transmittance can also be reduced.

[0040] In an exemplary embodiment, the total number of film layers in the preset stacking structure is greater than 4 and the third layer in the preset stacking structure is also an absorbent film layer. Exemplarily, the preset stacking structure is CLCL-[HL] m, where m is the number of repetitions of the structure in the brackets, for example, m=3, for example, m=5. Setting the first layer in the backlight direction as an absorption film layer and coating it on the substrate, and then setting the third layer as an absorption layer can increase the absorption rate of the black film to light, and have a lower transmittance, and the bonding strength between the absorption film layer and the body is high, which can improve the adhesion ability of the black film, and the internal stress is relatively balanced. Concentrating the refractive film layer more at the position facing the light source in the preset stacking structure is convenient for coating the black film, which can reduce the total thickness of the black film, and the staggered spacing film layer and refractive film layer can better reduce the reflection of light.

[0041] In an exemplary embodiment, the material of the absorption film layer includes a mixture of one or more of chromium (Cr), titanium (Ti), copper (Cu), silver (Ag), aluminum (Al), and silicon oxide; the material of the spacing film layer includes an oxide, nitride, or oxynitride of one or more of aluminum (Al), titanium (Ti), silicon (Si), tin (Sn), hafnium (Hf), tantalum (Ta), and yttrium (Y); the material of the refractive film layer includes titanium oxide, niobium pentoxide (Nb2O5), tantalum pentoxide (Ta2O5), hydrogenated silicon (SiH), hydrogenated silicon germanium (Si x Ge 1-x :H) and silicon carbide (SiC), wherein x satisfies 0<x<1. The material of the absorption film layer can absorb light, especially the wavelength band corresponding to visible light. The refractive index of the spacer film layer is usually lower than that of the refractive film layer. The spacer film layer and the refractive film layer can reduce the reflectivity and transmittance; when both sides of the spacer film layer are absorption film layers, the refractive index of the spacer film layer can be made equal to the refractive index of the refractive film layer at other positions. In a black film, the materials of each refractive film layer are usually the same to facilitate manufacturing. Of course, the materials of the refractive film layers at different positions can be different; the same is true for the absorption film layer and the spacer film layer.

[0042] In an exemplary embodiment, the material of the spacer film layer includes aluminum oxide (Al2O3) and silicon dioxide (SiO2); the material of the refractive film layer includes titanium pentoxide (Ti3O5). Exemplarily, the material of the absorption film layer includes a mixture of titanium and aluminum.

[0043] From the backlight side to the light-facing side, the black film includes: a first film layer, whose thickness is in the range of 80nm to 100nm, the first film layer is an absorption film layer, and its material includes chromium; a second film layer, whose thickness is in the range of 30nm to 50nm, the second film layer is a spacing film layer, and its material includes aluminum oxide and silicon dioxide; a third film layer, whose thickness is in the range of 10nm to 20nm, the third film layer is an absorption film layer, and its material includes chromium; a fourth film layer, whose thickness is in the range of 20nm to 40nm, the fourth film layer is a spacing layer, and its material includes aluminum oxide and silicon dioxide; a fifth film layer, whose thickness is in the range of 100nm to 120nm, the fifth film layer is a refractive film layer, and its material includes titanium pentoxide; and a sixth film layer, whose thickness is in the range of 80nm to 100nm, the sixth film layer is a spacing film layer, and its material includes aluminum oxide and silicon dioxide. Exemplarily, the thicknesses of the first to sixth film layers are 85nm, 35nm, 15nm, 25nm, 105nm and 85nm, respectively. The sixth film layer, the fifth film layer and the fourth film layer can reduce the reflectivity of the black film, the third film layer can absorb part of the light, and cooperate with the spacer film layer and the refractive film layer to reduce the reflectivity and transmittance of the black film. The first film layer is thicker and has a stronger ability to absorb light, so that the black film has the characteristics of high transmittance and high absorption.

[0044] In an exemplary embodiment, the thickness ratio of the first film layer set as the absorption film layer, the thickness of the second film layer set as the spacing film layer, the thickness of the third film layer set as the absorption film layer, the thickness of the fourth film layer set as the spacing film layer, the thickness of the fifth film layer set as the refractive film layer, and the thickness of the sixth film layer set as the spacing film layer is 9:4:1:2:10:8. Exemplarily, the thickness of each film layer from the first film layer to the sixth film layer is 99nm, 44nm, 11nm, 22nm, 110nm and 88nm, respectively. By limiting the ratio of the thickness of each film layer, the anti-reflection and absorption capabilities of the black film to light can be better improved.

[0045] In an exemplary embodiment, the refractive index n1 of the absorption film layer satisfies: 2.0≤n1≤4.0; the refractive index n2 of the spacing film layer satisfies: 1.4≤n2≤2.0; and the refractive index n3 of the refractive film layer satisfies: 2.0≤n3≤4.0. Exemplarily, the refractive index n1 of the absorption film layer is 3; the refractive index n2 of the spacing film layer is 1.6; and the refractive index n3 of the refractive film layer is 3.5. Exemplarily, the preset stacking structure is CLCLHLHL, the refractive index n1 of the absorption film layer is 2.7; the refractive index n3 of the refractive film layer is 2.0; the refractive index n2 of the spacing film layer between the two absorption film layers is 2.0, the refractive index n2 of the spacing film layer between the two refractive film layers is 1.5, and the refractive index n2 of the spacing film layer between the absorption film layer and the refractive film layer is 1.9. Controlling the refractive index of each film layer can control the deflection of light. Each film layer satisfies the aforementioned refractive index corresponding to the light of 550nm wavelength, so that the black film can better absorb visible light.

[0046] In an exemplary embodiment, the absorptivity Abs of the black film is greater than 95% for light in the wavelength range of 400nm to 780nm. Exemplarily, the absorptivity Abs of the black film is greater than 99% for light in the wavelength range of 400nm to 780nm. By absorbing more than 95% of the light, the black film appears black, and the black film absorbs most of the light irradiated thereon.

[0047] In an exemplary embodiment, the reflectivity R of the black film is less than 1% for light in the wavelength range of 400nm to 780nm. Exemplarily, the reflectivity R of the black film is less than 0.5% for light in the wavelength range of 400nm to 750nm. The black film has a smaller reflectivity, and when light shines on it, it reflects less light. The black film is applied to optical elements to reduce stray light.

[0048] In an exemplary embodiment, the transmittance T of the black film is less than 3% for light in the wavelength range of 400nm to 780nm. Exemplarily, the transmittance T of the black film is less than 0.5% for light in the wavelength range of 400nm to 750nm. The black film has a lower transmittance, and when light is irradiated thereon, it transmits less light. When the black film is coated on a transparent substrate, the area of ​​the transparent substrate coated with the black film transmits less light than other areas, and the light-transmitting area or the light-impermeable area of ​​the transparent substrate can be controlled.

[0049] Embodiment 1

[0050] Figure 1A schematic structural diagram of an optical element coated with a black film according to an embodiment of the present application is shown. The black film can be coated on an optical lens 100, and starting from the optical lens 100, the black film includes a first absorption film layer 201, a first spacing film layer 202, a second absorption film layer 203, a second spacing film layer 204, a refractive film layer 205, and a third spacing film layer 206.

[0051] The thickness of the first absorption film layer 201 is 90 nm, the thickness of the first spacing film layer 202 is 40 nm, the thickness of the second absorption film layer 203 is 10 nm, the thickness of the second spacing film layer 204 is 20 nm, the thickness of the refractive film layer 205 is 100 nm, and the thickness of the third spacing film layer 206 is 80 nm.

[0052] In this embodiment, the material of the absorption film layer is chromium (Cr), the material of the spacing film layer is a mixture of aluminum oxide (Al2O3) and silicon dioxide (SiO2), and the material of the refractive film layer 205 is titanium pentoxide (Ti3O5).

[0053] Reference Figure 2 The black film provided in this embodiment has a reflectivity R of less than 0.5% relative to light in the wavelength range of 400nm to 750nm, an average reflectivity of less than 0.4%, and a reflectivity R of less than 0.3% relative to light in the wavelength range of 400nm to 680nm. Figure 3 The black film provided in this embodiment has an absorptivity Abs greater than 95% for light in the wavelength range of 380nm to 780nm, and an absorptivity Abs greater than 98% for light in the wavelength range of 400nm to 600nm.

[0054] Embodiment 2

[0055] The black film can be coated on the optical lens 100. Starting from the optical lens 100, the black film includes a first absorption film layer 201, a first spacing film layer 202, a second absorption film layer 203, a second spacing film layer 204, a refractive film layer 205 and a third spacing film layer 206. The third spacing film layer 206 is a film layer facing the light, and the first absorption film layer 201 is a film layer facing away from the light. From the first absorption film layer 201 to the third spacing film layer 206, the ratio of the thickness of each film layer is 9:4:1:2:10:8, wherein the thickness of the first absorption film layer 21 is within 80nm to 100nm.

[0056] In this embodiment, the material of the absorption film layer is a mixture of silver (Ag) and copper (Cu), the material of the spacer film layer is a mixture of hafnium dioxide (HfO2), aluminum oxide (Al2O3) and yttrium oxide (Y2O3), and the material of the refractive film layer is a mixture of niobium pentoxide (Nb2O5) and tantalum pentoxide (Ta2O5).

[0057] Embodiment 3

[0058] The black film is stacked in layers in a CLCLHLHLCL structure, with the leftmost layer being coated on the optical lens 100 and the rightmost layer facing the light. Among them, the first layer, the third layer and the ninth layer are absorption layers, the materials of the first layer and the third layer are titanium (Ti), and the material of the ninth layer is silicon dioxide (SiO2); the material of the refractive layer is hydrogenated silicon (Si:H); the even-numbered layers are spacer layers, the material of the second layer is titanium nitride (Ti3N4), the material of the sixth layer is silicon dioxide (SiO2), and the materials of the remaining spacer layers are silicon nitride (Si3N4).

[0059] The embodiment of the present application also provides a lens barrel provided with the aforementioned black film, wherein the object side end of the lens barrel is provided with the black film. When the lens barrel is used to assemble a lens, the lens barrel provided with the black film at the object side end makes the incident light of the lens contain less stray light, and in addition, it can prevent the reflection of the lens from affecting the subject when taking close-up shots.

[0060] In an exemplary embodiment, the inner wall of the lens barrel is provided with a black film. If part of the light irradiated into the lens barrel hits the inner wall of the lens barrel, the part of the light will be absorbed by the black film and almost not reflected, so that the other part of the light used for imaging has less stray light and better imaging quality.

[0061] The embodiment of the present application also provides an annular spacer, comprising an annular main body and a black film coated on the outer side of the light-facing surface of the main body, the inner hole of the annular spacer is used to pass light, and the annular spacer is used to block light in the corresponding area of ​​the main body. The main body can be opaque, but the surface of the main body usually reflects light, so after the black film is set, most of the light irradiated on the annular spacer is absorbed to eliminate stray light in the light passing through the inner hole of the annular spacer.

[0062] The embodiment of the present application also provides an optical lens provided with the above-mentioned black film, the optical lens having an effective diameter area and a non-effective diameter area, and the non-effective diameter area is provided with a black film. The effective diameter area of ​​the optical lens is used for passing light to form an image, and the non-effective diameter area is mainly used for clamping and the like, so the black film is provided in the non-effective diameter area to absorb the light irradiated to the non-effective diameter area, so that the required light accounts for a higher proportion of the light in the imaging, and the image is clearer.

[0063] Reference Figure 4In an exemplary embodiment, the optical lens 100 has an effective radius area 101 and an ineffective radius area, and the ineffective radius area includes a black film area 102 and a supporting area 103. When the optical lens 100 is installed in the lens, the optical lens 100 is fixed by clamping the supporting area 103, and the effective radius area 101 is used to pass the imaging light, and the black film area 102 provided with a black film can absorb the light irradiated thereon, thereby preventing stray light from being mixed into the imaging light, and the imaging quality is good.

[0064] In an exemplary embodiment, a black film is coated on any one surface or both surfaces of the optical lens 100. The black film can be coated on the object side or image side of the optical lens 100, or on the peripheral surface. The black film can protect the optical lens 100 in all directions and prevent stray light from being generated.

[0065] In an exemplary embodiment, the absorbent film layer is formed by chemical coating.

[0066] In an exemplary embodiment, the black film is formed by local coating, which can control the area where the black film is located, so as to avoid the effective area of ​​the optical lens from being coated with the black film.

[0067] The embodiment of the present application also provides a method for coating a black film on an optical lens, the method comprising the following steps: using a non-fastening fixture to block the effective diameter area 101; and coating the black film area 102 with a black film.

[0068] The embodiment of the present application also provides an optical lens, comprising the optical element described above. The optical lens has an effective light channel; and the black film is arranged at a region of the optical lens outside the effective light channel.

[0069] Reference Figure 5 The optical lens comprises a lens barrel 300, a plurality of optical lenses 100 and a plurality of annular spacers 400. The optical lens has an effective light channel from the object side end of the lens barrel 30 to the imaging surface of the optical lens. Light incident on the effective light channel at a set angle outside the optical lens is used for imaging. The surfaces of the optical lens outside the effective light channel specifically include the object side end and the inner barrel wall of the lens barrel 300, the non-effective radius area of ​​the lens 100 and the surface of the annular spacer 400.

[0070] By arranging a black film on the surface of the optical lens outside the effective light channel, it is possible to prevent the light inside the optical lens and outside the effective light channel from forming stray light after reflection or diffuse reflection and entering the effective light channel. Preventing stray light can improve imaging quality.

[0071] In an exemplary embodiment, the optical lens includes the aforementioned lens barrel 300 or the aforementioned optical lens 100. The black film of the lens barrel 300 and the annular spacer 400 may be formed by coating at one time, and the optical lens 100 may include a black film formed by partial coating.

[0072] However, those skilled in the art will appreciate that the above embodiments are merely examples, and the black film may have other preset stacking structures, and multiple black films may be deposited simultaneously. Other film systems may also be disposed between the black film and the main body of the optical element.

[0073] The above description is only a preferred embodiment of the present application and an explanation of the technical principles used. Those skilled in the art should understand that the scope of protection involved in the present application is not limited to the technical solution formed by a specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the technical concept. For example, the above features are replaced with the technical features with similar functions disclosed in this application (but not limited to) by each other.

Claims

1. An optical element, comprising: ontology; as well as The black film plated on the body, The black film is characterized in that the black film is formed by stacking an absorption film layer, a spacing film layer and a refractive film layer in a certain order, wherein the refractive index of the spacing film layer is less than or equal to the refractive index of the refractive film layer; and The film layer closest to the body is the absorption film layer, the film layer farthest from the body is the spacing film layer, and the absorption film layer and the refractive film layer are not adjacent to each other; From the backlight side to the frontlight side, the black film includes, in sequence along a direction away from the body: a first film layer, a second film layer and at least two subsequent film layers, wherein the number of layers of the at least two subsequent film layers is an even number greater than 4; The first film layer is the absorption film layer, the third film layer disposed adjacent to the second film layer among the at least two subsequent film layers is the absorption film layer, the second film layer and the even-numbered layers among the at least two subsequent film layers are the spacing film layers, and the film layers among the at least two subsequent film layers except the third film layer and the spacing film layer are the refractive film layers; The material of the absorption film layer includes at least one of chromium, titanium, copper, silver, aluminum and silicon oxide; The refractive index of the absorption film layer is 2.7, the refractive index of the refractive film layer is 2.0, the refractive index of the second film layer is 2.0, the refractive index of the spacing film layer between the two refractive film layers is 1.5, and the refractive index of the spacing film layer between the absorption film layer and the refractive film layer is 1.

9.

2. The optical element according to claim 1, characterized in that The material of the spacer film layer includes at least one of oxides, nitrides and oxynitrides of aluminum, titanium, silicon, tin, hafnium, tantalum and yttrium; The material of the refractive film layer includes at least one of titanium oxide, niobium pentoxide, tantalum pentoxide, silicon hydride, hydrogenated silicon germanium and silicon carbide.

3. The optical element according to claim 2, characterized in that The material of the spacer film layer includes aluminum oxide and silicon dioxide; The material of the refractive film layer includes titanium pentoxide.

4. The optical element according to claim 1, characterized in that The thickness of the first film layer is in the range of 80 nm to 100 nm, and the material of the first film layer includes chromium; The thickness of the second film layer is in the range of 30 nm to 50 nm, and the material of the second film layer includes aluminum oxide and silicon dioxide; and The at least two subsequent film layers sequentially include, in a direction away from the body: A third film layer, which is the absorption film layer, has a thickness in a range of 10 nm to 20 nm, and is made of chromium; A fourth film layer, which is the spacer film layer, has a thickness in a range of 20 nm to 40 nm, and is made of aluminum oxide and silicon dioxide; A fifth film layer, which is the refractive film layer, has a thickness in a range of 100 nm to 120 nm, and is made of titanium pentoxide; The sixth film layer is the spacer film layer, the thickness of the sixth film layer is in the range of 80nm to 100nm, and the material of the sixth film layer includes aluminum oxide and silicon dioxide.

5. The optical element according to claim 4, characterized in that The thickness ratio of the first film layer, the second film layer, the third film layer, the fourth film layer, the fifth film layer and the sixth film layer is 9:4:1:2:10:

8.

6. The optical element according to claim 1, characterized in that Corresponding to light in the wavelength range of 400nm to 780nm, the absorption rate Abs of the black film is greater than 95%.

7. The optical element according to claim 1, characterized in that Corresponding to light in the wavelength range of 400nm to 780nm, the reflectivity R of the black film is less than 1%.

8. The optical element according to claim 1, characterized in that Corresponding to light in the wavelength range of 400nm to 780nm, the transmittance T of the black film is less than 3%.

9. The optical element according to claim 1, characterized in that The body is a lens barrel, and the black film is plated on the object side end of the lens barrel.

10. The optical element according to claim 1, characterized in that The main body is an optical lens having an effective diameter area and a non-effective diameter area, and the black film is plated on the non-effective diameter area.

11. The optical element according to claim 10, characterized in that Any one surface or both surfaces of the optical lens are coated with the black film.

12. The optical element according to claim 9, characterized in that The black film is formed by local coating.

13. The optical element according to claim 1, characterized in that The body is an annular spacer, and any one surface or both surfaces of the annular spacer are plated with the black film.

14. An optical lens, characterized in that: The optical lens comprises the optical element according to any one of claims 1 to 13.

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