Optical lens for reducing stray light
By using optical lenses with multi-layer film structures and edge-shielding designs, the problems of lens reflection, light leakage, and scattering from dirt have been solved, resulting in optical lenses with low stray light and improved imaging quality and stability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- CHENGDU HONGZHENG OPTICAL CO LTD
- Filing Date
- 2025-07-30
- Publication Date
- 2026-05-19
AI Technical Summary
Existing optical lenses are prone to reflection and stray light when light is incident. The lack of light-blocking treatment at the lens edges causes light to refract or leak out, and the lens surface is easily contaminated with dirt, resulting in scattering and affecting image quality.
The design employs a multi-layered film structure, consisting of a surface anti-reflective layer, an internal anti-reflective layer, an edge light-shielding section, and an anti-fouling protective layer. The surface anti-reflective layer is composed of titanium dioxide, silicon dioxide, and magnesium fluoride layers. The edge light-shielding section is a ring-shaped black nickel oxide coating, and the anti-fouling protective layer is a fluoropolymer film. These components are tightly bonded together using vacuum sputtering technology.
It significantly reduces surface reflection and edge light leakage, reduces stray light interference, maintains image clarity, and prevents smudge scattering, thereby improving the imaging quality and stability of the optical system.
Smart Images
Figure CN224263422U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of optical lens technology, and in particular to an optical lens that reduces stray light. Background Technology
[0002] Optical glass is made by mixing high-purity oxides of silicon, boron, sodium, potassium, zinc, lead, magnesium, calcium, barium, etc., according to a specific formula, melting them at high temperature in a platinum crucible, stirring them evenly with ultrasound to remove air bubbles, and then slowly cooling them for a long time to prevent internal stress from forming in the glass block. After cooling, the glass block must be measured by optical instruments to check whether its purity, transparency, uniformity, refractive index, and dispersion rate meet the specifications. Qualified glass blocks are then heated and forged to form optical lens blanks.
[0003] Existing optical lenses have significant shortcomings in stray light control, making it difficult to meet the needs of high-precision optical systems. They are prone to reflection when light is incident, forming stray light that interferes with image quality. Furthermore, the edges of the lenses are not light-shielding, allowing some light to refract or leak out, creating additional stray light. In addition, the lens surface is easily contaminated with dust, fingerprints, and other dirt, which scatter light and further increase stray light.
[0004] To address this, an optical lens for reducing stray light is proposed. Utility Model Content
[0005] The purpose of this invention is to provide an optical lens that reduces stray light. This invention solves the problems of existing optical lenses that easily reflect light when it is incident, forming stray light and interfering with image quality. In addition, the lens edges are not light-shielding, so some light is refracted or leaked from the edges, forming additional stray light. Furthermore, the lens surface is easily contaminated with dust, fingerprints and other stains, which scatter light and further increase stray light.
[0006] To achieve the above objectives, the present invention provides the following technical solution: an optical lens for reducing stray light, comprising a lens body, the lens body comprising an optical substrate layer, an internal anti-reflective layer provided inside the optical substrate layer, and a surface anti-reflective layer covering the outer surface of the optical substrate layer, an edge light-shielding portion wrapped around the edge of the optical substrate layer, and an anti-fouling protective layer covering the outer side of the surface anti-reflective layer.
[0007] Preferably, the surface antireflective layer is a multilayer film structure, comprising a titanium dioxide layer, a silicon dioxide layer, and a magnesium fluoride layer, wherein the titanium dioxide layer, silicon dioxide layer, and magnesium fluoride layer are sequentially disposed on the surface of the optical substrate layer from the inside to the outside.
[0008] Preferably, the thickness of the titanium dioxide layer is 50-80 nm, the thickness of the silicon dioxide layer is 150-200 nm, and the thickness of the magnesium fluoride layer is 100-150 nm.
[0009] Preferably, the reflectivity of the surface anti-reflection layer is ≤0.5%.
[0010] Preferably, the optical substrate layer is composed of high-purity fused silica glass, internally doped with cerium oxide, and the doping concentration is distributed in a gradient along the thickness direction.
[0011] Preferably, the thickness of the optical substrate layer is 1-5 mm, and the light transmittance is ≥95%.
[0012] Preferably, the internal antireflective layer is located 5-10 μm from the surface of the optical substrate layer, and is composed of silicon dioxide and magnesium fluoride, with the refractive index decreasing linearly from the inside to the outside.
[0013] Preferably, the antifouling protective layer is a fluoropolymer film with a thickness of 50-100 nm.
[0014] Preferably, the edge light-shielding portion is an annular black nickel oxide coating with a width of 1-2 mm, which is bonded to the edge of the optical substrate layer by vacuum sputtering.
[0015] Preferably, the outer side of the edge light-blocking part of the lens body is provided with a positioning groove, and the positioning groove is 0.5-1mm wide.
[0016] Compared with the prior art, the beneficial effects of this utility model are:
[0017] 1. The multilayer film structure of the surface antireflection layer in this application reduces reflection through light interference, and together with the internal antireflection layer, it suppresses internal scattering of the substrate, thereby reducing stray light generation from the source. The edge light-shielding part forms a tightly bonded black coating through vacuum sputtering, which effectively absorbs light refracted or leaked from the edge and avoids additional stray light interference.
[0018] 2. By setting an anti-fouling protective layer, this application can reduce the adhesion of dust and fingerprints, prevent stains from scattering light, and maintain the stability of stray light control effect. Attached Figure Description
[0019] Figure 1 This is an overall structural diagram of the optical lens for reducing stray light according to this utility model;
[0020] Figure 2 This is an exploded view of the lens body of this utility model;
[0021] Figure 3 This is an exploded view of the surface anti-reflection layer of this utility model;
[0022] Figure 4 This is a schematic diagram showing the connection between the optical substrate layer and the internal antireflective layer of this utility model.
[0023] In the diagram, 1 is the lens body; 2 is the optical substrate layer; 3 is the internal antireflective layer; 4 is the surface antireflective layer; 41 is the titanium dioxide layer; 42 is the silicon dioxide layer; 43 is the magnesium fluoride layer; 5 is the edge light-shielding part; 6 is the anti-fouling protective layer; and 7 is the positioning groove. Detailed Implementation
[0024] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0025] Please see Figure 1-4 The present invention provides the following technical solution:
[0026] An optical lens for reducing stray light includes a lens body 1, the lens body 1 includes an optical substrate layer 2, the interior of the optical substrate layer 2 is provided with an internal anti-reflection layer 3, and the outer surface of the optical substrate layer 2 is covered with a surface anti-reflection layer 4, the edge of the optical substrate layer 2 is wrapped with an edge light-shielding part 5, and the outer side of the surface anti-reflection layer 4 is covered with an anti-fouling protective layer 6.
[0027] In this embodiment, the lens body 1, through the synergistic design of the optical substrate layer 2, the internal antireflective layer 3, the surface antireflective layer 4, the edge light-shielding part 5, and the anti-fouling protective layer 6, forms an integrated structure that integrates substrate light transmission, internal scattering reduction, surface antireflection, edge light shielding, and surface anti-fouling protection. The internal antireflective layer 3 suppresses internal scattering of the substrate, the surface antireflective layer 4 reduces surface reflection, the edge light-shielding part 5 blocks edge light leakage, and the anti-fouling protective layer 6 avoids scattering from dirt. The multi-layer complementary functions comprehensively reduce stray light, solve the stray light problems caused by reflection, light leakage, and dirt scattering in traditional lenses, and improve the imaging quality of the optical system.
[0028] Specifically, such as Figure 3 As shown, the surface anti-reflection layer 4 is a multilayer film structure, which includes a titanium dioxide layer 41, a silicon dioxide layer 42, and a magnesium fluoride layer 43. The titanium dioxide layer 41, silicon dioxide layer 42, and magnesium fluoride layer 43 are sequentially disposed on the surface of the optical substrate layer 2 from the inside to the outside.
[0029] Specifically, such as Figure 3 As shown, the thickness of the titanium dioxide layer 41 is 50-80 nm, the thickness of the silicon dioxide layer 42 is 150-200 nm, and the thickness of the magnesium fluoride layer 43 is 100-150 nm.
[0030] Specifically, such as Figure 2 As shown, the reflectivity of the surface anti-reflection layer 4 is ≤0.5%.
[0031] In this embodiment, the surface anti-reflection layer 4 employs a multilayer film structure consisting of a titanium dioxide layer 41, a silicon dioxide layer 42, and a magnesium fluoride layer 43, arranged sequentially from the inside out. The high refractive index of titanium dioxide and the low refractive index of silicon dioxide and magnesium fluoride create a gradient change. Through the principle of destructive interference of light, the reflections of incident light of different wavelengths cancel each other out, significantly reducing stray light generated by surface reflection. This provides a more comprehensive anti-reflection effect than a single coating, adapting to multi-band light usage scenarios. The low reflectivity of the surface anti-reflection layer 4 can significantly reduce surface reflection when light is incident, reducing the interference of stray light formed by reflected light on the optical system, allowing more light to propagate along the predetermined path, improving imaging clarity and signal accuracy, and meeting the low stray light requirements of high-precision optical equipment.
[0032] Specifically, such as Figure 2 As shown, the optical substrate layer 2 is composed of high-purity fused silica glass, and is internally doped with cerium oxide, with the doping concentration distributed in a gradient along the thickness direction.
[0033] Specifically, such as Figure 2 As shown, the thickness of the optical substrate layer 2 is 1-5 mm, and the light transmittance is ≥95%.
[0034] In this embodiment: the optical substrate layer 2 is made of high-purity fused silica glass, which reduces light scattering caused by impurities; the cerium oxide doped inside is distributed in a gradient along the thickness direction, which can suppress scattering caused by uneven density inside the substrate, while improving the chemical stability and light transmission performance of the glass, reducing stray light formed by internal scattering from the source, and providing a stable light transmission basis for the lens; the high light transmittance ensures that most light can pass through effectively, reducing light loss caused by absorption, while reducing the probability of internal scattering of the substrate, avoiding stray light problems caused by insufficient light transmission or enhanced scattering.
[0035] Specifically, such as Figure 4 As shown, the internal antireflective layer 3 is located 5-10 μm from the surface of the optical substrate layer 2, and is composed of silicon dioxide and magnesium fluoride, with the refractive index decreasing linearly from the inside to the outside.
[0036] Specifically, such as Figure 2 As shown, the antifouling protective layer 6 is a fluoropolymer film with a thickness of 50-100nm.
[0037] In this embodiment: the internal antireflection layer 3 is located 5-10 μm from the surface of the optical substrate layer 2, which can specifically suppress scattering near the surface of the substrate (this area is prone to scattering due to processing or impurities). The linear decreasing refractive index structure composed of silicon dioxide and magnesium fluoride can smooth the propagation path of light inside the substrate, reduce scattering caused by abrupt changes in refractive index, and further reduce internal stray light. The antifouling protective layer 6 is made of a fluoropolymer film, whose low surface energy characteristics can reduce the adhesion of dirt such as dust and fingerprints, and prevent dirt from scattering light. The ultra-thin thickness of 50-100 nm does not affect light transmission. At the same time, it forms a physical barrier to protect the surface antireflection layer 4, maintain the long-term stability of the antireflection effect, and reduce the increase of stray light caused by cleaning or use.
[0038] Specifically, such as Figure 2 As shown, the edge light-shielding part 5 is an annular black nickel oxide coating with a width of 1-2 mm, which is bonded to the edge of the optical substrate layer 2 by vacuum sputtering.
[0039] Specifically, such as Figure 1 , Figure 2 As shown, a positioning groove 7 is provided on the outer side of the edge light-blocking part 5 of the lens body 1, and the positioning groove 7 is 0.5-1mm wide.
[0040] In this embodiment: the annular black nickel oxide coating of the edge light-shielding part 5 is tightly bonded to the edge of the optical substrate layer 2 by vacuum sputtering, making it difficult to fall off. The 1-2mm width can fully cover the edge of the lens, effectively absorbing light incident or refracted from the edge and blocking stray light formed by edge leakage. It is especially suitable for high-precision optical systems where edge light control is strict. The positioning groove 7 on the outer side of the edge light-shielding part 5 of the lens body 1 can realize the precise installation of the lens in the optical system, avoid edge leakage or abnormal light reflection angle caused by installation misalignment, and reduce additional stray light caused by installation error. The 0.5-1mm width design is compatible with common mounting clip structures, improving assembly convenience and stability.
[0041] Working Principle: During lens body 1 installation, the positioning groove 7, adapted to common mounting clip structures, installs the optical lens in the usage position. When the lens body 1 is in use, the surface anti-reflective layer 4 utilizes a multi-layer film structure consisting of titanium dioxide layer 41, silicon dioxide layer 42, and magnesium fluoride layer 43, arranged sequentially from the inside out. The high refractive index of titanium dioxide and the low refractive index of silicon dioxide and magnesium fluoride create a gradient change. Through the principle of destructive interference of light, the reflections of incident light of different wavelengths cancel each other out, significantly reducing stray light generated by surface reflection. This provides a more comprehensive anti-reflective effect than a single coating, adapting to multi-band light usage scenarios. The low reflectivity of the surface anti-reflective layer 4 significantly reduces surface reflection when light is incident, lowering... The stray light generated by reflected light interferes with the optical system, allowing more light to propagate along a predetermined path, improving imaging clarity and signal accuracy, meeting the low stray light requirements of high-precision optical equipment, and working in conjunction with the internal antireflection layer 3 to suppress internal scattering of the substrate, reducing stray light generation at the source. The edge light-shielding part 5 forms a tightly bonded black coating through vacuum sputtering, effectively absorbing light refracted or leaked from the edge, avoiding additional stray light interference. The anti-fouling protective layer 6, with its low surface energy characteristics, reduces the adhesion of dirt, fingerprints, and other stains, preventing stains from scattering light. At the same time, the physical barrier formed protects the surface anti-reflection layer 4, maintaining the long-term stability of the anti-reflection effect and reducing the increase of stray light caused by cleaning or use.
[0042] The above are merely preferred embodiments of the present utility model and are not intended to limit the present utility model. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.
Claims
1. An optical lens for reducing stray light, comprising a lens body (1), characterized in that: The lens body (1) includes an optical substrate layer (2), an internal anti-reflective layer (3) is provided inside the optical substrate layer (2), and a surface anti-reflective layer (4) is covered on the outer surface of the optical substrate layer (2). An edge light-blocking part (5) is wrapped around the edge of the optical substrate layer (2), and an anti-fouling protective layer (6) is covered on the outside of the surface anti-reflective layer (4).
2. The optical lens for reducing stray light according to claim 1, characterized in that: The surface anti-reflection layer (4) is a multilayer film structure. The surface anti-reflection layer (4) includes a titanium dioxide layer (41), a silicon dioxide layer (42), and a magnesium fluoride layer (43). The titanium dioxide layer (41), silicon dioxide layer (42), and magnesium fluoride layer (43) are sequentially disposed on the surface of the optical substrate layer (2) from the inside to the outside.
3. The optical lens for reducing stray light according to claim 2, characterized in that: The titanium dioxide layer (41) has a thickness of 50-80 nm, the silicon dioxide layer (42) has a thickness of 150-200 nm, and the magnesium fluoride layer (43) has a thickness of 100-150 nm.
4. The optical lens for reducing stray light according to claim 1, characterized in that: The reflectivity of the surface anti-reflection layer (4) is ≤0.5%.
5. An optical lens for reducing stray light according to claim 1, characterized in that: The optical substrate layer (2) is composed of high-purity fused silica glass, with cerium oxide doped inside, and the doping concentration is distributed in a gradient along the thickness direction.
6. An optical lens for reducing stray light according to claim 1, characterized in that: The thickness of the optical substrate layer (2) is 1-5 mm, and the light transmittance is ≥95%.
7. An optical lens for reducing stray light according to claim 1, characterized in that: The internal antireflective layer (3) is located 5-10 μm from the surface of the optical substrate layer (2), and is composed of silicon dioxide and magnesium fluoride, with the refractive index decreasing linearly from the inside to the outside.
8. An optical lens for reducing stray light according to claim 1, characterized in that: The antifouling protective layer (6) is a fluoropolymer film with a thickness of 50-100nm.
9. An optical lens for reducing stray light according to claim 1, characterized in that: The edge light-shielding part (5) is an annular black nickel oxide coating with a width of 1-2 mm, which is bonded to the edge of the optical substrate layer (2) by vacuum sputtering.
10. An optical lens for reducing stray light according to claim 1, characterized in that: The edge light-blocking part (5) of the lens body (1) is provided with a positioning groove (7) on the outside, and the positioning groove (7) is 0.5-1mm wide.