JPH0315163B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in the end face structure of a light guide cable for transmitting light energy to a desired location, and in particular, to improvement of the end face structure of a light guide cable for transmitting light energy to a desired location. The layer is removed to leave only the core portion, and around one core portion, multiple core portions are arranged in a hexagonal shape with the central core portion as the concentric center. An end portion of the light guide having a core portion having a smaller diameter than the core portion, located inside a circle circumscribing the core portion forming the outermost concentric hexagon and in a gap created between the core portions of the light guide. The end portion of the optical conductor cable is constructed by arranging the core portion from which the cladding layer has been removed, thereby increasing the mounting area of the optical conductor core on the end surface of the optical conductor cable with the same external dimensions, and improving the introduction efficiency of optical energy. This is intended to improve coupling efficiency.

Recently, we have entered an era of energy conservation, and research and development is being conducted in various fields on the effective use of solar energy. The applicant was one of the first to notice the effective use of solar energy, and has already made various proposals. , the use of energy without converting it into other forms of energy such as electricity or heat. Therefore, the present applicant has proposed that solar energy be focused and introduced into a light guide cable, and guided through the light guide cable to a location that requires illumination to provide illumination. In this way, by transmitting solar energy using a light conductor cable and illuminating with solar energy, there is no conversion loss and the like, and solar energy can be used most efficiently. but,
In reality, it is impossible to introduce all of the focused solar energy into the optical conductor cable, and the introduction efficiency is also low.

The present invention has been made in view of the above-mentioned circumstances, and in particular, removes the cladding layer at the end of a large number of optical conductors each having a circular cross-sectional shape, leaving only the core portion.
A number of core parts are bundled around one core part and arranged in a hexagon with the central core part being concentric, and the outermost concentric hexagon of the concentric hexagon is a gap formed within a circle circumscribing the core portion forming the light guide and between the core portions of the light guide;
A core portion having a core portion with a smaller diameter than the core portion and the cladding layer at the end portion of the optical waveguide is disposed to increase the mounting area of the optical waveguide core on the end face of the optical waveguide cable having the same external dimensions. , increasing the efficiency of solar energy introduction at the end face of the optical conductor cable,
Alternatively, the coupling efficiency when connecting optical conductor cables to each other is increased.

FIG. 1 is an end view of a light guide cable according to the present invention. As shown in the figure, the cladding layer at the end of the light guide having a circular cross-sectional shape is removed to leave only the core portion 1.
A large number of core parts 1 (7 in the case of FIG. 1) are bundled,
One of the cables is bundled into a concentric hexagonal shape ₁₀₁ to form the cable end. It is well known that the end face of a light guide cable is constructed by bundling a large number of light guides with circular cross-sections, but in the past, the cladding layers of the light guides were bundled as they were without cutting them, so it was difficult to connect them to the light guide cable. The introduction efficiency of optical energy or the coupling efficiency when connecting optical conductor cables together was poor. In order to eliminate these drawbacks, it is easy to think that it would be possible to remove the cladding layer at the end of the light guide and bundle only the core part, but in that case, it would be possible to simply bundle only the core part. In this case, a gap is created between the cores, and sufficient light energy introduction efficiency or coupling efficiency cannot be obtained. For example, as shown in FIG.
When arranging the cores 1, 1..., a gap is created between the cores 1, 1...
The total cross-sectional area of the light guide cores 1, 1... is a circle that includes these light guide cores 1, 1... (in other words, a circle that circumscribes the core part forming the outermost hexagon) 20 It is considerably smaller than the area of ₁ , about 78%
It is. Therefore, when sunlight is focused and introduced into a light guide cable using a suitable optical system such as a Fresnel lens, the most efficient way is to reduce the size of the solar image to the size of the light guide at the end face of the light guide cable. It is important to make the circle 20 ₁ that includes the cores 1, 1... identical, but if the cable end face is made up only of the photoconductor cores 1, 1..., even if the solar image is formed most efficiently in this way, Even if it is imaged, the light guide core 1,
1...The light that enters the gap between the cables is not transmitted within the optical conductor cable, so the upper limit of the efficiency of introducing solar energy into the optical conductor cable is 78%, which is not very efficient. Nakatsuta.

The present invention has been made in order to solve the above-mentioned drawbacks of the prior art. Core 2, 2...; 3, 3...
The efficiency of introducing solar energy into the optical fiber cable or the coupling efficiency of the optical fibers with each other is improved by arranging the optical fibers having the same structure. In the illustrated example, if the diameter of the light guide core 1 is 1 mm, then
The diameter of light guide core 2 is approximately 0.352 mm, and the diameter of light guide core 3 is approximately 0.352 mm.
The diameter of the light guide core 4 is approximately 0.17 mm, and the diameter of the light guide core 4 is approximately 0.17 mm.
0.156 mm, the diameter of the light guide core 5 is about 0.102 mm, the diameter of the light guide core 6 is about 0.062 mm, the diameter of the light guide core 7 is about 0.062 mm, there are 6 light guide cores 2, and 6 light guide cores 3. There are 12 light guide cores 4, 6 light guide cores 5, 18 light guide cores 5, 30 light guide cores 6, and 18 light guide cores 7, so the light guide cores 1, 1...
When the photoconductor cores 2, 2... are arranged in the gap, the total end area of the photoconductor cores accounts for approximately 86% of the area of the circle ₂₀₁ , and the photoconductor cores 1, 1...
This is considerably improved compared to the case where only ... is used. below,
Similarly calculated, when light guide cores 2 and 3 are installed, approximately 89.8%, light guide cores 2, 3, and 4
Approximately 91.5% when light guide cores 2, 3,
When light guide cores 4 and 5 are arranged, it is approximately 93.6%, when light guide cores 2-6 are arranged, it is 94.6%, and when light guide cores 2-7 are arranged, it is 95.4%. Light guide cores 1, 1...
This is considerably improved compared to the case where only ... is used, and further improved by arranging the light guide cores 8, 9, etc.

FIG. 2 is an end view for explaining another embodiment of the optical conductor cable end surface according to the present invention, with a diameter of 1 mm.
Using 19 light guide cores 1, light guide cores 1, 1...
FIG. _{2 is a diagram configuring an end surface of a light conductor cable having an end area of 5 mm in diameter and a circle 20 2} encompassing the . In this embodiment, the light guide cores 1, 1...
When constructed using only..., the light guide core 1
The ratio of the total end area of the circle 20 ₂ to the area of the circle 20 2 is 76%, but if 12 light guide cores 2' with a diameter of about 0.42 mm are arranged as shown in the figure, the light guide cores 1 and 2' The ratio of the total end area of ₂₀₂ to the area of circle 202 is approximately 84.5%, and in the same manner, if 12 additional light guide cores 3' with a diameter of 0.282 mm are arranged, the ratio is approximately 88%, and the ratio is approximately 88%, and the ratio of the area of the circle 202 is approximately 84.5%.
When 24 additional 0.156mm photoconductor cores 4 are installed, approximately
91%, when 12 additional light guide cores 5' with a diameter of approximately 0.175 mm are installed, approximately 92%; when 12 additional light guide cores 6' with a diameter of approximately 0.1 mm are installed, approximately 92.5%, with a diameter of approximately 0.062
If 72 mm photoconductor cores 7 are additionally provided, this becomes 93.5%, and it can be further improved by additionally providing photoconductor cores 8', 9', etc.

As is clear from the above description, according to the present invention, the mounting efficiency of the optical conductor core on the end face of the optical conductor cable is improved, and the efficiency of introducing solar energy into the optical conductor cable and the optical conductor cables are improved. Coupling efficiency when connecting can be improved.

In addition, FIG. 3 is a diagram for explaining a part of the manufacturing process of the optical conductor cable end face shown in FIG.
For example, the light guides 1, 1, . . . on the - line in FIG.
As shown in Fig. 3, the light guide core constituting the
Each light guide core 1, 1 is arranged in a row on the substrate 30.
The light guide core 4 and, if necessary, the light guide 7 are arranged in the upper gap adjacent to the light guide core 1, and the light guide core 1 is integrally constructed using an adhesive or the like, and in this way, the light guide core 1 is integrated. The structure is reversed and the light guide core 4 and, if necessary, the light guide core 7 are integrated with the light guide core 1 in the same manner as described above, and as a result, the light guide core 4 and the light guide core 7 are integrated with the light guide core 1, and as a result, the light guide core 4 and the light guide core 7 are integrated with the light guide core 1 in the same manner as described above. A semi-finished product in which the light guide core 1, the light guide core 4, and if necessary the light guide core 7 are integrally constructed as shown is manufactured, and in the same way, the light guide core corresponding to the - line in FIG. 2 is manufactured. 1, 1... are also constructed integrally with the light guide core 4 and, if necessary, the light guide core 7, as shown on the - line in FIG. 3, and these integrally constructed semi-finished products are stacked. Then, the same operation is performed on one side of the optical conductor core 1 on the - line in FIG. 2, and these are overlapped as shown in FIG. Conductor core 2', 3',
5', 6', 8', 9', etc. may be glued.

In addition, when producing in large quantities, Figure 3-
It is preferable to spin semi-finished products as shown by the lines and - and finally overlap and bond them together.

As is clear from the above description, according to the present invention, the mounting efficiency of the optical conductor core on the end face of the optical conductor cable can be significantly improved, and therefore,
It is possible to improve the introduction efficiency when introducing optical energy into the optical conductor cable and the coupling efficiency when connecting the optical conductor cables together.

[Brief explanation of drawings]

1 and 2 are end views of a light guide cable according to the present invention, respectively, and FIG. 3 is a diagram showing a part of the process of manufacturing the end portion of the light guide cable shown in FIG. 2. 1 to 12...Light guide core.

Claims (1)

[Claims] 1 Cut off the cladding layer at the end of a large number of light guides with a circular cross-sectional shape to leave only the core part, and then bundle the many core parts around one core part to form a core part around the center. The core portions are arranged in a hexagonal shape having concentric core portions, and a gap is formed within a circle circumscribing the core portion forming the outermost concentric hexagon of the concentric hexagons and between the core portions of the light guide. 1. An end surface structure of an optical waveguide cable for illumination light, characterized in that a core area having a core area smaller in diameter than the core area is provided by cutting off the cladding layer at the end of the optical waveguide.