JP2001264570A - Optical transmitting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical transmitting device having simple constitution capable of always surely transmitting light between each of plural light emitting elements or light receiving elements provided on two relatively rotating substrates. SOLUTION: The optical transmitting device is provided with an optical transmitting means composed of a first optical transmitting means fixed to a first substrate side and a second optical transmitting means fixed to a second substrate side. The first optical transmitting means is separated from the second transmitting means by a gap, and the optical axis of transmitting light between the first optical transmitting means and the second optical transmitting means coincides with the rotating axis of relative rotation of the first substrate to the second substrate in at least a part of the gap.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical transmission apparatus for transmitting and receiving light between a plurality of light-emitting or light-receiving elements, which are respectively mounted on two relatively rotating substrates.

[0002]

2. Description of the Related Art Between a plurality of light-emitting or light-receiving elements provided on a substrate and a plurality of light-emitting or light-receiving elements provided on a substrate rotating relative to the substrate,
When transmitting light, unless the light emitting element or the light receiving element is installed at a position that coincides with the relative rotation axis of the substrates, the positional relationship between the light emitting element and the light receiving element is It always fluctuates according to the rotation. For this reason, the conventional method of simply projecting the image of the light emitting element on the light receiving surface of the light receiving element by the imaging lens cannot perform stable light transmission.

Further, a plurality of pairs of light emitting and receiving elements for transmitting and receiving are arranged at an equal distance from a rotation axis of relative rotation between the substrates, and their relative rotation is determined by one of the rotations.
There is a related art in which transmission / reception is enabled by canceling with an image rotator rotating at a rotation speed of / 2. However, since a rotation speed reduction mechanism or the like for rotating the image rotator is required, the device is very difficult. However, there is a drawback that it becomes complicated and becomes large.

[0004] Further, according to a method in which each light emitting element and each light receiving element are coupled by an optical fiber, the rotation of the substrate that rotates relative to one substrate is limited by the coupled optical fiber. The problem that occurs.

[0005]

SUMMARY OF THE INVENTION Accordingly, the present invention provides a plurality of light emitting or light receiving elements mounted on a substrate and a plurality of light emitting or light receiving elements mounted on a substrate that rotates relative to the substrate. It is an object of the present invention to provide an optical transmission device having a simple configuration capable of constantly and reliably transmitting light between a light emitting or light receiving element.

[0006]

In order to achieve the above-mentioned object, the present invention provides a method according to claim 1, wherein
A plurality of light emitting elements are provided, and a plurality of light receiving elements are provided on the second substrate, or at least one light emitting element and at least one light receiving element are provided on the first substrate. And, when at least one light emitting element and at least one light receiving element are provided on the second substrate, and the first substrate is configured to rotate relative to the second substrate, Transmission light emitted from one light-emitting element provided on the first substrate is provided on the second substrate, so as to be incident on one light-receiving element corresponding to the light-emitting element, When the at least one light-emitting element is provided on the second substrate, the transmission light emitted from the light-emitting element is transmitted to the one light-receiving element corresponding to the light-emitting element provided on the first substrate. So that it enters the element A light transmitting unit for transmitting and receiving light between each of the light emitting elements and each of the light receiving elements, wherein the light transmitting unit includes a first light transmitting unit fixed to the first substrate side; And a second optical transmission means fixed to the second substrate side, wherein the first optical transmission means is provided to prevent the relative rotation of the first substrate with respect to the second substrate from being restricted. Means and the second optical transmission means,
The second substrate of the first substrate is separated by a gap, and the optical axis of the transmission light between the first optical transmission unit and the second optical transmission unit is at least part of the gap. The optical transmission device is characterized by being coincident with the rotation axis of relative rotation with respect to.

Further, in claim 2, in the optical transmission device according to claim 1, the first optical transmission means includes the plurality of light emitting elements provided on the first substrate, or the at least one light emitting element. The two light-emitting elements and the at least one light-receiving element, the end faces on the gap side of the optical fibers corresponding one by one, the end faces of the respective optical fibers are concentric around the rotation axis. A first multi-branch optical fiber bundled so as to form a layer of
The optical transmission unit is disposed with the gap between the first multi-branch optical fiber and the plurality of light receiving elements provided on the fixed substrate, or the at least one light receiving element and the at least one light emitting element. The gap-side end face of the optical fiber corresponding to each of the elements, one by one, is formed as a concentric layer having a shape similar to the gap-side end face of the first multi-branch optical fiber. 2nd bundled in
A multi-branch optical fiber, wherein a concentric layer of the first multi-branch optical fiber and a concentric layer of the second multi-branch optical fiber are provided on the first substrate of the first multi-branch optical fiber The light emitted from the layer corresponding to the light-emitting element of the second multi-branch optical fiber is incident on the layer of the second multi-branch optical fiber combined with the light receiving element on the second substrate. And the light emitted from the layer combined with the light emitting element on the second substrate is incident on the layer of the first multi-branch optical fiber corresponding to the light receiving element on the first substrate. Wherein the center of the first multi-branch optical fiber and the center of the second multi-branch optical fiber opposing each other with the gap therebetween are configured to be present on the rotation axis. The optical transmission device.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Either a plurality of light emitting elements are provided on a first substrate and a plurality of light receiving elements are provided on a second substrate, or at least one light emitting element is provided on the first substrate. A light emitting element and at least one light receiving element are provided, and at least one light emitting element and at least one light receiving element are provided on the second substrate, and the first substrate is positioned relative to the second substrate. It is a configuration that rotates
When light transmission is performed between each light emitting element and each light receiving element, the most important problem is that the two substrates are relatively rotating. And at this time,
The only point on the first substrate that always has a fixed positional relationship with a point on the second substrate is a point that coincides with the rotation axis of the relative rotation of the first substrate with respect to the second substrate. Therefore, in order to perform stable optical transmission, transmission light for performing optical transmission between a plurality of optical elements provided on the first substrate and a plurality of optical elements provided on the second substrate is required. Gathering on or near the axis of rotation of the first substrate relative to the second substrate;
It is necessary to perform optical transmission.

For this purpose, light from a light emitting element installed on the first substrate is guided to the first substrate side to the rotation axis of the first substrate relative to the second substrate or in the vicinity thereof. When the light receiving element is provided on the first substrate, the first light transmission means for guiding the light incident near the rotation axis to the light receiving element provided on the first substrate is provided by the first light transmitting means. It needs to be fixed on the substrate. Further, when a light emitting element is provided on the second substrate also on the second substrate side,
Light from the light-emitting element provided on the second substrate is guided to a position corresponding to the rotation axis of the first substrate relative to the second substrate or a position corresponding to the vicinity thereof, and is directed to the rotation axis or the vicinity thereof. It is necessary to provide a second optical transmission means for guiding the light incident at the corresponding position to the light receiving element provided on the second substrate.

[0010] In order for the optical transmission means comprising the first optical transmission means and the second optical transmission means not to limit the relative rotation between the first substrate and the second substrate, the first optical transmission means and the second optical transmission means are required. It is necessary that the light transfer means is separated from the air gap by a gap and is not in direct physical contact with the light transfer means.

Further, even if the first optical transmission means rotates relative to the second optical transmission means with the relative rotation of the first substrate and the second substrate, the first optical transmission means and In order to always transmit and receive transmission light stably to and from the second optical transmission means, the optical axis of the transmission light is required to rotate at least in part of the air gap relative to the rotation of the first substrate with respect to the second substrate. Must match the axis of rotation.

In particular, the rotation of the first substrate relative to the second substrate at least at a position immediately after the optical axis of the transmission light emitted from the center of the first optical transmission means is emitted from the first optical transmission means. And the optical axis of the transmission light incident on the center of the first optical transmission means at least at a position immediately before entering the first optical transmission means. With the axis of rotation of the relative rotation with respect to.

With such a configuration, an optical transmission having a small size and a simple configuration capable of always performing stable optical transmission between the first optical transmission means and the second optical transmission means without requiring a complicated mechanism. The device can be configured.

[0014] The term "immediately before the transmission light is incident on the first optical transmission means" or "immediately after the transmission light is emitted from the first optical transmission means" as described herein means that the end face of the first optical transmission means on the air gap side,
It refers to the distance between the second optical transmission means or the optical element located closest to the first optical transmission means inserted into the gap and the end face on the first optical transmission means side.

At this time, as the optical element inserted into the gap, for example, the optical element for improving the transmission efficiency of the light between the gap-side end face of the first optical transmission means and the gap-side end face of the second optical transmission means is provided. When the relay lens or the first substrate and the second substrate are not opposed to each other, for example, are arranged on planes orthogonal to each other, in order to deflect the direction of the transmission light in the gap, Examples include a prism and a mirror.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram of a first embodiment of the present invention.

In the first embodiment, the rotation axis A
A light emitting element 3 and a light receiving element 4 are provided one by one on a first substrate 1 which rotates relatively to a second substrate 2 around X. Also, on the second substrate 2, one light emitting element 5 and one light receiving element 6 are provided.

On the side of the first substrate 1, a first multi-branch optical fiber 7 is fixed.
The light emitting element 3 is provided on the outer layer of the first multi-branch optical fiber 7.
The light receiving element 4 corresponds to the layer inside.

On the second substrate 2 side, a second multi-branch optical fiber 8 is fixed with an air gap 9 therebetween.
The light emitting element 5 is provided on the inner layer of the multi-branch optical fiber 8 in the second layer.
The light receiving element 6 corresponds to the outer layer of the multi-branch optical fiber 8. FIG. 1 shows the second substrate 2 in a see-through state.

At this time, the end face of the first multi-branch optical fiber 7 on the side of the gap 9 and the end face of the second multi-branch optical fiber 8 on the side of the gap 9 are vertically opposed to and close to the rotation axis AX. The center of the first multi-branch optical fiber 7 and the center of the second multi-branch optical fiber 8 are on the rotation axis AX. The end face of the first multi-branch optical fiber 7 on the gap 9 side and the end face of the second multi-branch optical fiber 8 on the gap 9 side are as follows:
They have the same shape. At this time, the optical axis of the transmission light between the first multi-branch optical fiber 7 and the second multi-branch optical fiber 8 coincides with the rotation axis AX.

Therefore, even when the first substrate 1 is rotating, the positional relationship between the end face of the first multi-branch optical fiber 7 on the gap 9 side and the end face of the second multi-branch optical fiber 8 on the gap 9 side is completely changed. Instead, the transmission light from the light emitting element 3 emitted from the layer outside the first multi-branch optical fiber 7 enters the layer outside the second multi-branch optical fiber 8, is guided to the light receiving element 6, and The transmission light from the light emitting element 5 emitted from the layer inside the two-branch optical fiber 8 enters the layer inside the first multi-branch optical fiber 7.

Further, in the first multi-branch optical fiber 7 and the second multi-branch optical fiber 8, the outer side and the inner side of the gap-side end face are clearly separated from each other in order to clearly separate the boundary portions between the outer and inner layers. A separation layer may be provided between the layer and the inner layer.

With such a configuration, the light emitting element 3 on the first substrate 1 and the light receiving element 6 on the second substrate, or the light emitting element 5 on the second substrate, which rotate relative to the second substrate, Optical transmission can always be performed efficiently with the light receiving element 4 on the first substrate that rotates relatively to the second substrate.

In this embodiment, the number of the light emitting element and the number of the light receiving element on the first substrate 1 and the number of the light emitting element and the light receiving element on the second substrate 2 are one each. Even if the number of light receiving elements is further increased,
This can be dealt with by increasing the number of branches of the multi-branch optical fiber and the second multi-branch optical fiber in accordance with the number of light emitting or light receiving elements.

FIG. 2 is a block diagram of a second embodiment of the present invention.

In the second embodiment, based on the configuration of the first embodiment, a collimator lens 10 is added to each light emitting or light receiving element side of each optical fiber in order to increase the light transmission efficiency. In order to improve the light transmission efficiency between the branch optical fiber 7 and the second multi-branch optical fiber 8, the air gap 9 is provided.
And a relay lens 11 is added to FIG. At this time,
The optical axis of the relay lens 11 matches the rotation axis AX, and the optical axis of the transmission light emitted from the center of the first multi-branch optical fiber matches the rotation axis AX. The center of the end face of the first multi-branch optical fiber 7 on the side of the gap 9 and the center of the end face of the second multi-branch optical fiber 8 on the side of the gap 9 correspond to the rotation axis A.
It is configured to be on X.

In the second embodiment, the magnification of the relay lens 11 is the same, and the shape of the first multi-branch optical fiber 7 on the gap 9 side and the shape of the second multi-branch optical fiber on the gap 9 side are different. Are the same. However, even when the magnification of the relay lens 11 is set to a value other than the same magnification, the first multi-branch optical fiber 7
The shape on the side of the gap 9 and the shape on the side of the gap 9 of the second multi-branch optical fiber may be similar to each other in accordance with the magnification of the relay lens 11.

Further, as the collimating lens 10 and the relay lens 11, a lens array or DOE
Etc. can also be used.

[0030]

As described above, according to the present invention, a plurality of light-emitting or light-receiving elements provided on a substrate and a plurality of light-emitting or light-receiving elements provided on a substrate rotating relative to the substrate are provided. ,
An optical transmission device having a small and simple configuration capable of always reliably transmitting and receiving light to and from a light emitting or light receiving element can be configured.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a first embodiment of the present invention.

FIG. 2 is a configuration diagram of a second embodiment of the present invention.

[Description of Signs] 1 First substrate 2 Second substrate 3 Light emitting element 3 4 Light receiving element 4 5 Light emitting element 5 6 Light receiving element 6 7 First multi-branch optical fiber 8 Second multi-branch optical fiber 9 Air gap 10 Collimating lens 11 Relay Lens R Rotation center of relative rotation of first substrate 1 with respect to second substrate 2 AX Rotation axis of relative rotation of first substrate 1 with respect to second substrate 2

Claims (2)

[Claims] 1. A plurality of light emitting elements are provided on a first substrate, and a plurality of light receiving elements are provided on a second substrate, or at least one light emitting element is provided on the first substrate. An element and at least one light receiving element are provided, and at least one light emitting element and at least one light receiving element are provided on the second substrate, wherein the first substrate is provided with respect to the second substrate. When it is configured to rotate relatively, the transmission light emitted from one light emitting element installed on the first substrate, one light emitting element corresponding to the light emitting element installed on the second substrate So that it is incident on the light receiving element,
When the at least one light emitting element is provided on the second substrate, the transmission light emitted from the light emitting element is provided on the first substrate, and one of the light emitting elements corresponding to the light emitting element is provided on the first substrate. A light transmitting unit for transmitting and receiving light between each of the light emitting elements and each of the light receiving elements so as to be incident on a light receiving element; and the light transmitting means is fixed to the first substrate side. And a second optical transmission means fixed to the second substrate side, in order to prevent the relative rotation of the first substrate with respect to the second substrate from being restricted. The first optical transmission means and the second optical transmission means are separated by a gap, and the optical axis of the transmission light between the first optical transmission means and the second optical transmission means, In at least a part of the gap, the first substrate An optical transmission device, wherein the optical transmission device coincides with a rotation axis of relative rotation with respect to the second substrate. 2. The light transmitting device according to claim 1, wherein the first light transmitting unit is provided for each of the plurality of light emitting elements provided on the first substrate, or each of the at least one light emitting element and the at least one light receiving element. A first multi-branch optical fiber in which the end faces on the gap side of the corresponding optical fibers are bundled such that the end faces of the respective optical fibers form a concentric layer around the rotation axis; The second optical transmission means is disposed with the gap between the first multi-branch optical fiber and the plurality of light receiving elements provided on the first substrate, or the at least one light receiving element and the at least one light receiving element. One light-emitting element, the gap-side end face of the optical fiber corresponding to each one of the light-emitting elements, a concentric layer having a shape similar to the gap-side end face of the first multi-branch optical fiber. To A second multi-branch optical fiber bundled to form a concentric layer of the first multi-branch optical fiber;
The concentric layer of the multi-branch optical fiber means that the light emitted from the layer corresponding to the light emitting element on the first substrate of the first multi-branch optical fiber is the second light of the second multi-branch optical fiber. The light emitted from the layer of the second multi-branch optical fiber combined with the light emitting element on the second substrate is incident on the layer combined with the light receiving element on the substrate. The center of the first multi-branch optical fiber and the second multi-branch optical fiber are respectively configured so as to be incident on a layer corresponding to a light receiving element on the first substrate of the branch optical fiber, and face each other across the gap. The optical transmission device according to claim 1, wherein a center of the branch optical fiber is configured to exist on the rotation axis.