JPS624684B2 - - Google Patents

Description

TECHNICAL FIELD The present invention relates to an optical branching device for branching a part of optical energy propagated within a light guide and taking it out of the light guide.

Prior Art The present applicant has previously proposed that sunlight or artificial light is focused by a lens or the like, introduced into a light guide, and transmitted through the light guide to any desired location for illumination or other uses. Various proposals were made. In this case, if the light energy propagating within the light guide can be branched and extracted from the light guide during its propagation, the efficiency of use of light energy can be further improved.

In view of the above-mentioned circumstances, the present applicant previously proposed an optical branching device capable of branching and extracting part of the light energy propagated within a light guide rod from the light guide rod.

FIG. 3 is a front view for explaining an example of an optical branching device previously proposed by the present applicant, and FIG. 4 is a cross-sectional view. In the figure, 1 is a first light guide rod; The conductor rod 1 has a through hole in the radial direction,
A second light guide rod 2 and a third light guide rod 3 are fitted into the through hole, and the second light guide rod 2 is fixed with optical glue or the like. The end of the second light guide rod 2 in the penetration hole is formed into an inclined surface 2a with respect to the axial direction of the first light guide rod, and the third light guide rod 3 is formed at an inclined surface 2a with respect to the axial direction of the first light guide rod. It has an inclined surface 3a opposite to the inclined surface 2a of No. 2. Further, the third light guide rod 3 is fitted into the through hole so as to be able to move forward and backward, and a groove 3b is provided at the upper end along the axial direction of the light guide rod. Injecting optical oil 5 into the gap d between the inclined surface 2a of the second light guide rod 2 and the inclined surface 3a of the third light guide rod 3,
Further, when the third light guide rod 3 is advanced or retreated, the air in the gap is exhausted or air is introduced into the gap to facilitate the movement of the third light guide rod 3. After injecting the optical oil 5 into the gap d in this way, when the third light guide rod 3 is pushed forward, the gap in the gap d becomes narrower and the level of the optical oil increases, and conversely, when it degenerates, As the gap d becomes wider, the level of the optical oil 5 decreases. Therefore, the light L propagated in the direction of arrow A within the first light guide rod 1 is transmitted to the inclined surface 2a of the second light guide rod 2 in the part where the optical oil is not contained in the gap. Therefore, it is reflected and travels in the direction of arrow B, and in the part where optical oil is contained, it travels in the direction of arrow C. At this time, the amount of light traveling in the direction of arrow B is adjusted by the level of optical oil 5 in the gap. This adjustment can be made by adjusting the depth of insertion of the third light guide rod 3. 4 is a fourth light guide rod fixed to the outer peripheral surface of the light guide rod 1 so as to cover the fitting portion of the second light guide rod 2, or formed integrally with the second light guide rod; The light branched in the direction of arrow B as described above is taken out through the fourth light guide rod 4,
The light is transmitted to any desired location through a light guide cable (not shown) connected to the fourth light guide rod 4, and is used for illumination or other purposes. However, the optical branching device described above has optical oil 5 between the inclined surfaces.
However, it communicates with the atmosphere through a groove 3a provided in the third optical guide rod 3, and the optical oil may leak through the groove 3a, or dust in the outside air may mix into the optical oil through the groove 3a. However, it had the disadvantage that it could not withstand use for many years. Furthermore, since the groove 3a is an air layer, light scattering occurs there, resulting in a large loss of optical energy.

Purpose The present invention has been made in order to eliminate the drawbacks of the prior art as described above, and in particular, the communication between the optical oil and the outside air is cut off to prevent the optical oil from dissipating or dust from entering the optical oil. The purpose of this design is to provide an optical branching device with a long life by preventing the contamination of

Configuration Fig. 1 is a plan sectional view for explaining an embodiment of the optical branching device according to the present invention, and Fig. 2 is a side sectional view, which is the same as in Figs. 3 and 4. The same reference numerals as in FIGS. 3 and 4 are given to the parts that act. 1 and 2, reference numeral 10 indicates the inclined surface 3 of the third light guide rod 3.
A cover member is liquid-tightly fixed to the first light guide rod 1 so as to cover the end 3c side opposite to the side a, and an optical oil 11 is sealed in the cover member 10. There is. Further, a permanent magnet 15 is integrally attached to the protrusion 3c side of the third light guide rod 3, and a permanent magnet 1 of opposite polarity is disposed on the outside of the cover 10, facing the permanent magnet 15.
6 is attached to the third light guide rod 3 so as to be movable in the axial direction. Therefore, the permanent magnet 1
6 in the direction of arrow E, the third light guide rod 3 also moves in the direction of arrow E, and the second light guide rod 2
The distance between the inclined surface of the third light guide rod 3 and the inclined surface of the third light guide rod 3 becomes narrower, and conversely, if the third light guide rod 3 moves in the direction of the arrow F, the third light guide rod 3 also moves in the direction of the arrow F and the third light guide rod 3 is moved in the direction of the arrow F. The distance between the surfaces is widened, and the light energy propagated in the direction of arrow A within the light guide rod 1 can be branched in the direction of arrows B or C in the same manner as described in the prior art.
In this way, in the present invention, since the optical oil 5 is completely isolated from the outside air, there is no possibility that the optical oil will dissipate or that dust will be mixed into the optical oil, thereby extending the life of the device. can be achieved. Also, in this case, when the gap d between the inclined surfaces is minimized, the groove provided in the third light guide rod 3
3b is filled with the optical oil 5, and conversely,
When the gap d between the inclined surfaces is maximum, the optical oil 11
When the groove 3b is filled with
Scattering of light energy at the part b is reduced, and loss of light energy can be reduced. 13
is a stopper/volume adjustment screw provided on the cover 10. The screw 13 is operated from the outside of the cover 10 to regulate the amount of protrusion into the cover. In addition to regulating the movement in the F direction, the volume of the portion of the cover member containing the optical oil is adjusted so that when the third light guide rod 3 is moved in the direction of the arrow F, the optical oil 11 flows into the groove 3b. I try to adjust the amount that goes inside. It should be noted that it is easy to understand that the stopper function and the volume adjustment function may be constructed from separate members.

Effects As is clear from the above description, according to the present invention, it is possible to provide an optical branching device that has a long life and has less optical energy loss.

[Brief explanation of the drawing]

FIG. 1 is a plan sectional view (cross-sectional view taken along the - line in FIG. 2) for explaining one embodiment of the optical branching device according to the present invention, FIG. 2 is a sectional view, and FIG. 3 is a conventional optical branching device. A front view for explaining an example of the device, and FIG. 4 is a sectional view. DESCRIPTION OF SYMBOLS 1...First light guide rod, 2...Second light guide rod, 3...Third light guide rod, 4...Fourth light guide rod, 5...Optical oil, 10...
Cover member, 11... Optical oil, 13... Stopper/volume adjustment screw, 15, 16... Permanent magnet.

Claims (1)

[Scope of Claims] 1. A first light guide rod having a through hole in the radial direction, and a rod that is inserted and fixed halfway into the through hole so that the end within the through hole extends in the axial direction of the first light guide rod. In contrast, a second light guide rod is formed on an inclined surface, and the second light guide rod is fitted into the remainder of the through hole so that its end within the through hole engages with the inclined surface of the second light guide rod. and a fourth light guide rod fixed to the outer circumferential surface of the first light guide rod so as to cover the fitting portion of the second light guide rod; Optical oil is sealed between the inclined surface of the second light guide rod and the inclined surface of the third light guide rod in the through hole, and the third light guide rod can move forward and backward into the through hole. In the fitted optical branching device, a cover member is fixed to the outer peripheral surface of the first light guide rod, liquid-tightly covering the end of the third light guide rod opposite to the inclined surface side. an optical oil in the cover member, and the optical oil in the cover member and the optical oil between the inclined surfaces are arranged above the third light guide rod along the axial direction of the light guide rod. What is claimed is: 1. An optical branching device characterized in that the optical branching device is configured to be able to communicate through a groove provided therein. 2. A permanent magnet is provided in a portion of the third light guide rod that protrudes into the cover member, and
Claim 1, wherein a permanent magnet is provided on the outside of the cover member, and the third light guide rod is moved by the permanent magnet on the outside of the cover member. Optical branching device. 3. The optical branching device according to claim 1 or 2, further comprising a volume adjustment mechanism that can increase or decrease the volume of the optical oil sealing portion within the cover member. 4. Claims 1 to 4, characterized in that when the distance between the inclined surfaces is at a minimum, the optical oil within the distance fills the groove of the third light guide rod. The optical branching device according to any one of Item 3. 5. The optical oil in the cover member is configured to fill the groove of the third light guide rod when the distance between the inclined surfaces is at a maximum. The optical branching device according to any one of Item 4. 6. The optical branching device according to any one of claims 1 to 5, characterized in that the cover member includes a stopper for regulating the maximum amount of protrusion of the third light guide rod. .