JPH0411843B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to an optical branching device that branches part of the optical energy propagated within a light guide and takes 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. There was no such branching means, which was extremely inconvenient.

Purpose The present invention was made in view of the above-mentioned circumstances, and in particular, provides an optical branching device that can branch and extract a part of the light energy propagated within a cylindrical light guide from the light guide. It was made with the purpose of providing.

Configuration FIG. 1 is a cross-sectional configuration diagram for explaining an embodiment of the optical branching device according to the present invention. In the figure, 1 is a cylindrical first light guide, and 2 is the first light guide 1. 3 is a cylindrical second light guide having the same diameter as , and 3 is a cylindrical third light guide, and the light output end surface A of the first light guide 1 is an inclined surface.
A ₁ and a plane A ₂ following the inclined surface A ₁ , and the light receiving end surface B of the second light guide 2 is formed by the first light guide 1 .
It is formed by an inclined surface B _{1 that engages with the inclined surface A 1 of} the light emitting end surface and a flat surface B ₂ that follows the inclined surface B ₁ , and has a circular slot 2a in the center of the inclined surface. Also, the third
As shown in the figure, the light guide 3 is arranged such that its light receiving end is located at a position facing the hole 2a on the outer peripheral surface of the first light guide 1. Therefore, light guide 1
Part of the light energy L ₀ that has been propagated through
_L1 is reflected by an inclined surface corresponding to the hole 2a of the light guide 1 and branched into a third light guide 3;
The remaining light energy L ₀ -L ₁ is propagated through the second light guide 2. Since the amount of branched light is related to the area of the hole 2a, the area of the hole 2a may be changed depending on the amount of branched light required. For example, the light energy _L0 propagated through the first light guide 1
When you want to branch out and extract 1/4 of the energy,
The area of the hole 2a may be set to 1/4 of the area of the first light guide. The inclined surfaces of the first light guide 1 and the second light guide 2 are connected using optical glue, optical gel, optical mating oil, etc., but in this case, the engagement of both light guides ( (junction) surface, that is, the light-emitting end surface A of the first light guide 1 and the light-receiving end surface B of the second light guide 2
is formed by slopes A ₁ and B ₁ and planes A ₂ and B ₂ following these slopes, and is the intersection line of slope A ₁ and plane A ₂ , and is the intersection line of slope B ₁ and plane B When the inclined surfaces A ₁ , B ₁ and the planes A 2 , B ₂ are formed into concave and convex surfaces that complementarily engage with each other so that the intersection line P, which is also the intersection line with _{2 ,} is perpendicular to the axis of the light guide, When manufacturing the first light guide 1 and the second light guide 2, a single cylindrical light guide is prepared, and the cylindrical light guide is moved along an inclined surface from the _S1 direction in FIG. If you cut from the direction S2 to the position P, then cut from the direction _S2 to the position P, the first light guide 1 and the second light guide 2 will be cut.
can be obtained easily. Moreover, in this case, no part is wasted. Moreover, after processing the holes 2a etc. on the inclined surface of the second light guide as described above, alignment is required when bonding the first light guide and the second light guide with optical glue or the like. becomes very easy. Further, although the holes 2a are shown parallel to the axis of the light guide 2 in the illustrated example, it will be readily understood that they may be formed in a direction perpendicular to the inclined surface, as shown in FIG.

Effects As is clear from the above explanation, according to the present invention, since the engaging surface is composed of two planes, it is possible to effectively split light energy with an easy-to-manufacture configuration, and it is possible to effectively split light energy during connection work. It is possible to provide an optical branching device that is easy to align.

[Brief explanation of drawings]

FIGS. 1 and 2 are cross-sectional configuration diagrams of essential parts for explaining embodiments of the optical branching device according to the present invention, respectively. 1...First light guide, 2...Second light guide, 3
...Third light guide, A... Light output end face of light guide 1,
B... Light-receiving end surface of the light guide 2, P... Uneven surface portion that engages in a complementary manner.

Claims (1)

[Claims] 1. A cylindrical first light guide having a part of its light emitting end surface formed as an inclined surface, and a slanted surface having the same diameter as the first light guide and having a part of its light receiving end surface engaged with said inclined surface. a cylindrical second light guide having a circular hole formed in a part of the inclined surface thereof, and a light receiving end disposed at a position facing the hole on the outer peripheral surface of the first light guide. the light emitting end face of the first light guide and the light receiving end face of the second light guide are comprised of the inclined surface and a plane following the inclined surface, and the inclined surface and the plane, the line of intersection forming a line of intersection perpendicular to the central axes of the first and second light guides.