KR-20260066897-A - Glass Optical Fiber for High-power Beam Transmission and Its Manufacturing Method

KR20260066897AKR 20260066897 AKR20260066897 AKR 20260066897AKR-20260066897-A

Abstract

A glass optical fiber for high-power beam transmission and a method for manufacturing the same are disclosed. According to one embodiment of the present invention, an optical fiber is provided that comprises a core, a first cladding layer located on the outer edge of the core and implemented with a preset component, and a second cladding layer located on the outer edge of the first cladding layer.

Inventors

김윤현

Assignees

한국광기술원

Dates

Publication Date: 20260512
Application Date: 20241105

Claims (14)

Core; A first cladding layer located on the outer edge of the above-mentioned core and implemented with a preset component; and A second cladding layer located on the outer edge of the first cladding layer. Optical fiber characterized by including
In paragraph 1, The above core is, Optical fiber characterized by being implemented with silica ( SiO2 ).
In paragraph 1, The first cladding layer above is, Optical fiber characterized by being implemented with silica doped with fluoride ions.
In paragraph 1, The above second cladding layer is, Optical fiber characterized by being implemented with silica.
In paragraph 1, The above core is, An optical fiber characterized by having a relatively large refractive index compared to the first cladding layer.
In paragraph 1, The above second cladding layer is, An optical fiber characterized by having a relatively large refractive index compared to the first cladding layer.
Core; A first cladding layer located on the outer edge of the above-mentioned core and implemented with a preset component; A second cladding layer located on the outer edge of the first cladding layer; and A coating area implemented on the outer edge of the second cladding layer. Optical fiber characterized by including
In Paragraph 7, The above coating area is, Optical fiber characterized by having a preset refractive index.
In paragraph 8, The above coating area is, An optical fiber characterized by having a refractive index greater than that of the second cladding layer.
In Paragraph 9, The refractive index set above is, An optical fiber characterized by being implemented to be at least 0.015 greater than the refractive index of the second cladding layer.
In a method for manufacturing optical fibers, A deposition process for depositing a second cladding layer, a first cladding layer, and a core; A sintering process for sintering the composition deposited in the above deposition process; and An etching process for etching the second cladding layer to a preset thickness after sintering in the above sintering process. A method for manufacturing an optical fiber characterized by including
In Paragraph 11, The above sintering process is, A method for manufacturing an optical fiber characterized by proceeding in a sintering form and ensuring that each deposited component is vitrified.
In Paragraph 11, The above sintering process is, A method for manufacturing an optical fiber characterized by proceeding in a collapsing form and changing the shape of each deposited component.
An optical fiber manufactured according to the manufacturing method of any one of paragraphs 11 to 13.

Description

Glass Optical Fiber for High-power Beam Transmission and Its Manufacturing Method The present invention relates to a glass optical fiber capable of transmitting a high-power beam and a method for manufacturing the same. The content described in this section merely provides background information regarding the present embodiment and does not constitute prior art. High-power fiber laser light sources using large-diameter optical fibers can be used as next-generation optical communication, medical, industrial processing equipment, and military laser light sources, and are characterized by low signal loss and the ability to obtain high output. One of the key optical characteristics required for beam transmission optical fibers is the numerical aperture (NA). The numerical aperture is a characteristic that determines the angle of incidence and the angle of exit when light is incident or emitted from the optical fiber; the larger the numerical aperture, the larger the angle of incidence or exit of light that can be transmitted through the optical fiber. Depending on the application, optical fibers with beam transmission capabilities may require an appropriate numerical aperture at a certain level, or they may require an optical fiber with the largest possible numerical aperture. In particular, in the latter case, to increase the numerical aperture of the optical fiber, the difference in refractive index between the optical fiber core and the cladding must be large. To achieve this, the refractive index of the core is generally increased and the refractive index of the cladding is lowered. However, in optical fibers with silica-based glass cores and claddings, the change in refractive index caused by additive materials that increase the refractive index in the core region or decrease the refractive index in the cladding region tends to gradually decrease rather than increase linearly, and there is a problem in that it is fundamentally difficult to achieve a concentration of the additive material within the silica above a certain level. Consequently, there is a limitation in achieving a difference in refractive index between the core and the cladding above a certain level during the manufacturing process of optical fiber preforms. Accordingly, methods to increase the numerical aperture of silica-based glass optical fibers for beam transmission by coating the silica-based core glass with a polymer material having a low refractive index to increase the difference in refractive index between the core and the cladding have been proposed and utilized. However, while this approach is useful for transmitting low-power beams, it presents a problem for high-power beam transmission because the cladding coating material cannot withstand the heat generated by the high-power beam. Therefore, for high-power beam transmission, a method is required to maximize the difference in refractive index between the silica-based glass core and the cladding. FIG. 1 is a flowchart illustrating a method for manufacturing a glass optical fiber according to one embodiment of the present invention. FIG. 2 is a diagram illustrating the structure of a glass optical fiber according to one embodiment of the present invention. Figure 3 is a graph showing the refractive index distribution of a glass optical fiber according to one embodiment of the present invention. Figure 4 is a diagram illustrating the structure of a conventional glass optical fiber. Figure 5 is a graph showing the refractive index distribution of a conventional glass optical fiber. The present invention is susceptible to various modifications and may have various embodiments, and specific embodiments are illustrated in the drawings and described in detail. However, this is not intended to limit the invention to specific embodiments, and it should be understood that the invention includes all modifications, equivalents, and substitutions that fall within the spirit and scope of the invention. Similar reference numerals have been used for similar components in the description of each drawing. Terms such as first, second, A, B, etc., may be used to describe various components, but said components should not be limited by said terms. These terms are used solely for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be named the second component, and similarly, the second component may be named the first component. The term "and/or" includes a combination of a plurality of related described items or any of a plurality of related described items. When it is stated that one component is "connected" or "connected" to another component, it should be understood that while it may be directly connected or connected to that other component, there may also be other components in between. On the other hand, when it is stated that one component is "directly connected" or "directly connected" to an