Plastic optical fiber and optical fiber transmission system
By using a non-PFAS material for the core and cladding, and introducing a sub-core layer between the core and cladding, the PFAS risk in plastic optical fibers is solved, resulting in an environmentally friendly optical fiber product with good optical performance and material selectivity.
Patent Information
- Application Number
- CN202410605424.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-15
- Publication Date
- 2025-11-18
AI Technical Summary
Existing plastic optical fibers contain fluoropolymer materials (PFAS), which pose environmental durability and health risks. There is a need to develop PFAS-free plastic optical fibers to meet regulatory requirements and environmental friendliness.
The core and cladding are made of non-PFAS plastic materials to ensure that the refractive index difference between the core and cladding is large enough. A sub-core layer is introduced between the core and cladding to avoid vulcanizing agent poisoning. Silicone rubber is used as the cladding material and cross-linking is used to improve the curing effect.
It has achieved PFAS-free plastic optical fibers that meet regulatory requirements, maintain good optical performance and environmental friendliness, while improving the fiber curing effect and the flexibility of material selection.
Smart Images
Figure CN120972306A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] Embodiments of the present disclosure generally relate to the field of optical fibers, and more particularly, to PFAS (Per- & Polyfluoroalkyl Substances)-free plastic optical fibers, and optical fiber transmission systems equipped with such plastic optical fibers. BACKGROUND
[0002] A plastic optical fiber is a kind of optical fiber made of high-transparency plastic material. Due to its light weight, softness, damage resistance, strong conduction ability, low cost, no radiation, no influence of electromagnetic and radio frequency interference and noise, the plastic optical fiber has a wide range of applications in many fields including communication, automotive industry, industrial control, consumer electronics, home network and smart home, medical equipment, lighting, etc.
[0003] Generally, a plastic optical fiber mainly includes a core for guiding the propagation of light therein and a cladding having a lower refractive index than the core to reflect and refract the light propagating in the core, and a fluorine-containing polymer material generally has a relatively low refractive index, and thus is one of the most common materials of the cladding in a conventional plastic optical fiber.
[0004] Then, the fluorine-containing polymer belongs to a PFAS material, and the PFAS material is called a “persistent organic compound (POPs)” because it takes hundreds of years to degrade in soil and water, and the PFAS is also easy to migrate in the environment, and when people and animals ingest the PFAS, the PFAS accumulates in the organism and is toxic, affects the immune system, the reproductive system, interferes with the endocrine system, and has potential carcinogenicity, i.e., so-called PFAS risk. Therefore, in recent years, as the research goes deeper, the health risks brought by the PFAS have attracted more and more attention from countries, and countries and regions around the world are working hard to formulate relevant regulations and policies to strengthen the control of the PFAS. Therefore, in order to meet the requirements of the PFAS regulations and policies of relevant countries or regions and remove the PFAS risk, it is necessary to reduce or avoid the use of PFAS materials such as fluorine-containing polymers in plastic optical fibers. SUMMARY
[0005] One object of the present disclosure is to solve or overcome at least one of the above and other problems and defects existing in the prior art.
[0006] According to one aspect of the present disclosure, a plastic optical fiber is provided, which includes a core and a cladding circumferentially wrapping the core, the core and the cladding are both made of a non-PFAS plastic material.
[0007] In some embodiments, the cladding is made of a non-fluorine-containing polymer material.
[0008] In some embodiments, the refractive index of the core is greater than the refractive index of the cladding, and the refractive index difference between the core and the cladding is greater than or equal to 0.04.
[0009] In some embodiments, the refractive index difference between the core and the cladding is greater than or equal to 0.1.
[0010] In some embodiments, the material of the core is selected from one of polymethyl methacrylate (PMMA), acryl-based block copolymer, polyurethane (PU), and acrylic polymer.
[0011] In some embodiments, the material of the cladding includes one of silicone rubber (SR) and poly 4-methyl pentene-1 (TPX) material.
[0012] In some embodiments, the cladding is a silicone rubber layer.
[0013] In some embodiments, the plastic optical fiber further includes a sub-core layer wrapped on an outer peripheral surface of the core and located between the core and the cladding.
[0014] In some embodiments, the sub-core layer is formed of a light-transmitting material having a refractive index greater than or equal to the refractive index of the core and greater than the refractive index of the cladding.
[0015] In some embodiments, the sub-core layer is formed of a light-transmitting material having a refractive index slightly less than the refractive index of the core and greater than the refractive index of the cladding.
[0016] In some embodiments, a cross-linking bonding ability between the sub-core layer and the cladding is greater than a cross-linking bonding ability between the core and the cladding.
[0017] In some embodiments, the material of the sub-core layer includes polymethyl methacrylate (PMMA) or a thermoplastic elastomer material.
[0018] In some embodiments, the cladding is cured on an outer peripheral surface of the sub-core layer.
[0019] According to another aspect of the present disclosure, embodiments also provide an optical fiber transmission system including a light source assembly having a light source and a plastic optical fiber as described in any of the embodiments of the present disclosure, one end of the plastic optical fiber being coupled to the light source assembly to receive and propagate light from the light source.
[0020] In some embodiments, the optical fiber transmission system is a vehicle lamp illumination system.
[0021] Other objects and advantages of the present disclosure will be readily apparent and become more fully understood as the present disclosure is described hereinafter with reference to the accompanying drawings. Attached Figure Description
[0022] These and / or other aspects, features, and advantages of this disclosure will become apparent and readily understood from the following description of illustrative embodiments, taken in conjunction with the accompanying drawings, in which:
[0023] Figure 1 This is a perspective view schematically illustrating the structure of an optical fiber transmission system according to exemplary embodiments of the present disclosure;
[0024] Figure 2 This is a schematic cross-sectional view illustrating the structure of an optical fiber transmission system according to an exemplary embodiment of the present disclosure;
[0025] Figure 3 This is a schematic diagram illustrating a plastic optical fiber according to an exemplary embodiment of the present disclosure;
[0026] Figure 4 This is a cross-sectional view showing the structure of a plastic optical fiber according to an exemplary embodiment of the present disclosure;
[0027] Figure 5 This is an end view showing the structure of a plastic optical fiber according to an exemplary embodiment of the present disclosure;
[0028] Figure 6 This is a cross-sectional view showing the structure of a plastic optical fiber according to another exemplary embodiment of the present disclosure; and
[0029] Figure 7 This is an end view illustrating the structure of a plastic optical fiber according to another exemplary embodiment of the present disclosure. Detailed Implementation
[0030] The embodiments of this disclosure will now be described in detail with reference to the accompanying drawings. In this specification, identical or similar components are indicated by identical or similar reference numerals. The following description of embodiments of this disclosure with reference to the accompanying drawings is intended to explain the overall concept of this disclosure and should not be construed as a limitation thereof.
[0031] Furthermore, in the following detailed description, numerous specific details are set forth for ease of explanation to provide a thorough understanding of embodiments of the present disclosure. However, it will be apparent that one or more embodiments may be practiced without these specific details. In other instances, well-known structures and apparatuses are illustrated to simplify the figures.
[0032] Exemplary embodiments of the present disclosure provide plastic optical fibers, which can be used as optical transmission medium for communication, lighting, etc., including but not limited to local area network networking, fiber to the home, automotive lighting or signal indication, vehicle or airborne communication, control and sensing systems, home networking, connection of smart home or medical devices, etc., other various lighting or light utilization systems, etc.
[0033] Exemplary embodiments of the present disclosure also provide optical fiber transmission systems including or equipped with such plastic optical fibers, including but not limited to for vehicle lighting systems. As an example, referring to Figure 1 and 2 , the optical fiber transmission system can include a light source assembly 1 and a plastic optical fiber 100, the light source assembly 1 including a light source 10, which can be a light emitter including a light source, a driver, a modulator, etc. in a communication system, the light source 10 can include a laser light source or an LED light source. As an example, as shown in Figure 2 , the light source assembly 1 can include a housing 11 and a circuit board 12 mounted in the housing 11, the light source 10 can be mounted on the circuit board 12, and the housing 11 can be provided or formed with a heat dissipation structure 13. One end of the plastic optical fiber 100 can be optically coupled to the light source assembly 1 to receive light from the light source 1; the other end of the plastic optical fiber 100 can be connected with a light receiver or a fiber connector 2 for optical coupling with other devices, or can be coupled to the light source assembly. It will be understood that Figure 1 and 2 The illustrated system configuration including the plastic optical fiber 100 is merely an example, and the present disclosure is not limited thereto.
[0034] In the illustrated embodiment, as shown in Figures 3-7 , the plastic optical fiber mainly includes a core 110 and a cladding 120, the cladding 120 circumferentially wrapping the core 110 along the length of the core 110, light incident into the core 110 from the light source 10 propagates in the core 110. The core, also known as the core layer, has a relatively high refractive index and is the main medium for transmitting optical signals; the cladding, also known as the skin layer, has a relatively low refractive index and is used to reflect and refract optical signals. It will be understood that in other embodiments, the plastic optical fiber can also include a coating layer and / or an outer sheath, the coating layer covering the cladding to provide a protective effect for the optical fiber.
[0035] In order to realize the optical transmission function of the optical fiber, the refractive index of the cladding needs to be lower than that of the core, the larger the difference between the refractive indices of the two, the less the light leakage, and the higher the optical transmission efficiency, so the cladding needs to use a material with a relatively low refractive index. Fluorine-containing polymer materials, such as FEP (fluorinated ethylene propylene copolymer), ETFE (ethylene-tetrafluoroethylene copolymer), PVDF (polyvinylidene fluoride), etc., have a relatively low refractive index and are common materials for the cladding of conventional plastic optical fibers. However, fluorine-containing polymers belong to PFAS materials and have a “PFAS” risk.
[0036] Therefore, in the plastic optical fiber provided according to the embodiments of the present disclosure, at least the cladding 120 is made of a non-PFAS plastic material (i.e., the plastic material does not contain PFAS or is PFAS-free), and preferably both the core 110 and the cladding 120 are made of a non-PFAS plastic material, thereby avoiding the “PFAS” risk, so that the optical fiber product meets the requirements of relevant regulations and policies and is environmentally friendly. For example, the cladding 120 of the plastic optical fiber is made of a non-fluorine-containing polymer material, and preferably both the core 110 and the cladding 120 of the plastic optical fiber are made of a non-fluorine-containing polymer material.
[0037] In exemplary embodiments, the refractive index (RI) of the core 110 is greater than that of the cladding 120, and the refractive index difference between the core 110 and the cladding 120 is greater than or equal to 0.04, preferably greater than or equal to 0.06, and more preferably greater than or equal to 0.1, so that the optical fiber has good optical performance, including transmission distance, illuminance, optical loss, etc.
[0038] As an example, the material of the core 110 can be selected from at least one of methyl methacrylate (MMA), polymethyl methacrylate (PMMA), an acrylic-based block copolymer, polyurethane (PU), thermoplastic polyurethane (TPU), an acrylic polymer, etc. In this context, the material of the core can refer to an unmodified material, and / or can refer to a modified material including additives, modifiers or dopants, such as modified PMMA, which can have at least one of improved optical or physical properties, such as light transmittance, thermal stability, refractive index, optical transmission loss, etc., relative to the unmodified material itself. For example, the modified PMMA can include MAM (an acrylic-based block copolymer), which is a modified material based on PMMA and has good flexibility and weather resistance.
[0039] As an example, the material of the cladding 120 can include silicone rubber (SR) or poly 4-methyl pentene-1 (TPX) material. For example, the material forming the cladding can be silicone rubber, including heat curable silicone rubber or solid silicone rubber (HCR), liquid silicone rubber (LSR), etc. Exemplarily, the cladding can be formed by an extrusion process or a coating process. Also, the material of the cladding described herein can refer to unmodified material or modified material. The plastic optical fiber provided according to embodiments of the present disclosure can have the same or better flexibility as conventional flexible plastic optical fiber.
[0040] The following table lists some examples of the material of the core and the cladding of the plastic optical fiber.
[0041]
[0042]
[0043] In some exemplary embodiments of the present disclosure, the cladding 120 can be a cured silicone rubber layer. In the case of forming the cladding by silicone rubber, the cross-linking reaction of the silicone rubber can be facilitated by means of a vulcanizing agent (such as platinum vulcanizing agent or bis-24 or bis-25 vulcanizing agent) to cure the silicone rubber on the outer peripheral surface of the core. Generally, some polymer materials (including raw materials, modified materials, doped materials, additives, etc.) forming the plastic optical fiber (such as the core thereof) can contain N (nitrogen), P (phosphorus), S (sulfur), Pb (lead), Cd (cadmium), polyacetylene family or related substances, which can cause the catalyst activity in the vulcanizing agent to decline or lose, also known as vulcanizing agent poisoning, which in turn causes the cross-linking or curing of the silicone rubber to fail.
[0044] In some exemplary embodiments of the present disclosure, as shown in Figure 6 and 7 The plastic optical fiber can further include a sub-core layer 130 wrapped on the outer peripheral surface of the core 110 along the length of the core 110 and located between the core 110 and the cladding 120, i.e., the cladding 120 is not directly formed on the outer peripheral surface of the core 110, but is wrapped (such as extruded or coated) and cured on the outer peripheral surface of the sub-core layer 130, to avoid the risk of vulcanizing agent poisoning or curing failure.
[0045] Preferably, the cross-linking bonding ability between the sub-core layer 130 and the cladding layer 120 is greater than the cross-linking bonding ability between the cladding layer 120 and the core 110, that is, the cladding layer is more easily vulcanized on the surface of the sub-core layer 130, thereby facilitating the curing of the cladding layer 120 on the peripheral surface of the sub-core layer 130. Cross-linking bonding refers to the bonding of two or more molecules to each other to form more stable molecules with a network structure, thereby improving the strength, heat resistance, wear resistance, and other properties of the material. In the present application, the sub-core layer 130 ensures that the catalyst in the cladding layer 120 remains active, and the cladding layer 120 is more easily vulcanized on the surface of the sub-core layer 130 than the core 110.
[0046] The sub-core layer can also be formed of a light-transmitting material that does not affect the optical function of the optical fiber. The refractive index of the sub-core layer 130 is greater than or equal to the refractive index of the core 110, for example, preferably, the refractive index of the sub-core layer 130 can be approximately the same as the refractive index of the core 110, such as the difference between the refractive indices of the sub-core layer 130 and the core 110 being within the range of ±0.02, and the refractive index of the sub-core layer 130 is greater than the refractive index of the cladding layer 120. For example, the sub-core layer 130 can be formed of the same base material as the core 110, such as a non-modified polymer transparent material. In some examples, the sub-core layer 130 is formed of a light-transmitting material that has a refractive index that can be slightly less than the refractive index of the core 110 and greater than the refractive index of the cladding layer 120, but the refractive index of the sub-core layer 130 needs to be close to the refractive index of the core 110. In some examples, the material of the sub-core layer includes polymethyl methacrylate (PMMA), a thermoplastic elastomer material, or other suitable materials.
[0047] According to some example embodiments of the present disclosure, the presence of a sub-core layer between the core and the cladding layer of the plastic optical fiber can solve the problem of silicone vulcanization poisoning, making the vulcanization and curing of silicone more effective; and since the core does not directly contact the silicone and does not affect the curing of the silicone, as needed, modified materials, doped materials, additives, etc. for performance improvement can be included in the material of the core, making the selection of the material of the core more flexible and the performance improvement more flexible.
[0048] Although the present disclosure is illustrated with reference to the accompanying drawings, the embodiments disclosed in the drawings are intended to exemplarily illustrate the preferred embodiments of the present disclosure and cannot be understood as a limitation of the present disclosure. The dimensional proportions in the drawings are merely illustrative and cannot be understood as a limitation of the present disclosure.
[0049] Although some embodiments of the general concept of the present disclosure have been shown and described, those of ordinary skill in the art will understand that changes can be made to these embodiments without departing from the principles and spirit of the general concept of the present disclosure, and the scope of the present disclosure is defined by the claims and their equivalents.
Claims
1. A plastic optical fiber comprising a core (110) and a cladding (120), the cladding circumferentially enclosing the core. in, Both the core and the cladding are made of non-PFAS plastic materials.
2. The plastic optical fiber according to claim 1, wherein, The cladding is made of a non-fluoropolymer material.
3. The plastic optical fiber according to claim 1, wherein, The refractive index of the fiber core is greater than that of the cladding, and the refractive index difference between the fiber core and the cladding is greater than or equal to 0.
04.
4. The plastic optical fiber according to claim 3, wherein, The refractive index difference between the fiber core and the cladding is greater than or equal to 0.
1.
5. The plastic optical fiber according to claim 1, wherein, The core material includes one of polymethyl methacrylate (PMMA), acrylic block copolymer, polyurethane (PU), and acrylic polymer.
6. The plastic optical fiber according to any one of claims 1-5, wherein, The cladding material is selected from either silicone rubber (SR) or poly(4-methylpentene-1) (TPX).
7. The plastic optical fiber according to claim 6, wherein, The cladding is a silicone rubber layer.
8. The plastic optical fiber according to any one of claims 1-7, wherein, The plastic optical fiber further includes a sub-core layer (130), which wraps around the outer peripheral surface of the core and is located between the core and the cladding.
9. The plastic optical fiber according to claim 8, wherein, The sub-core layer is formed of a light-transmitting material with a refractive index greater than or equal to the refractive index of the core and greater than the refractive index of the cladding.
10. The plastic optical fiber according to claim 8, wherein, The sub-core layer is formed of a light-transmitting material with a refractive index slightly lower than that of the core and greater than that of the cladding.
11. The plastic optical fiber according to any one of claims 8-10, wherein, The cross-linking bonding ability between the sub-core layer and the cladding is greater than that between the core and the cladding, and the cladding is more likely to cure on the surface of the sub-core layer.
12. The plastic optical fiber according to claim 8, wherein, The material of the sub-fiber core layer includes polymethyl methacrylate (PMMA) or thermoplastic elastomer material.
13. The plastic optical fiber according to claim 8, wherein, The cladding is solidified on the outer peripheral surface of the sub-fiber core layer.
14. An optical fiber transmission system, comprising: A light source assembly (1) including a light source (10); and The plastic optical fiber according to any one of claims 1-13, wherein at least one end of the plastic optical fiber is coupled to the light source assembly to receive and propagate light from the light source.
15. The optical fiber transmission system according to claim 14, wherein, The fiber optic transmission system is used in the vehicle lighting system.