JPH0573610U - Light guide device with controlled entrance and exit angles - Google Patents

Abstract

(57) [Abstract] [Purpose] It is possible to improve the connection characteristics between an optical fiber and an optical element such as a light emitting and receiving element, and reduce the influence of reflected return light by controlling the entrance and exit angles. To provide a light guide device capable of performing. [Structure] An optical fiber 3 accommodating V-groove 5 is formed on the surface of the silicon single crystal material 1 in parallel with the surface, and at the predetermined position at the end of the V groove 5 on the surface of the silicon single crystal material. An optical element 4 is provided. The end surface 7 of the V-shaped groove 5 forming a reflection surface facing the end surface of the optical fiber 3 is used for connecting the optical fiber and the optical element in which the end surface 7 is formed at a predetermined inclination angle with respect to the axial direction of the optical fiber 3. .. The end face in the axial direction of the optical fiber 3 is formed so as to have a predetermined inclination angle with respect to the perpendicular of the axial line of the optical fiber 3.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a light guide device used for optical connection between an optical fiber and an optical element, and more specifically, to a V groove (a groove having a V-shaped cross section in the axial direction) formed on a <111> silicon single crystal. The present invention relates to a light guide device in which an optical fiber is accommodated, and an incident / emission angle is controlled so that the optical fiber is reflected by a reflection surface formed on the end surface of the V-groove to enter / emit the optical fiber.

[0002]

[Prior Art]

 Conventionally, a light guide device using a single crystal silicon material has been used for the connection between this type of optical fiber and the optical element. FIG. 4 is a diagram showing a relationship of optical axes of a conventional light guide device. In the following description, the optical element will be described as a light receiving element for convenience. That is, in the light guide device shown in FIG. 4, the V-groove 5 for accommodating the optical fiber 3 in the <111> silicon single crystal material 1 and the optical element provided above the end of the V-groove for the light beam emitted from the optical fiber 3 are provided. Since the reflection end face 7 having a predetermined inclination angle to be incident on the No. 4 is formed by <11 1> silicon single crystal anisotropic etching, the inclination angle of the reflection end face 5 is set only to 54.7 °. It is a thing.

[0003]

[Problems to be solved by the device]

 Therefore, when the light emitted from the optical fiber 3 is reflected by the reflection termination surface 7, the optical axis of the light emitted is not perpendicular to the surface 9 on which the optical element 4 is mounted. This means that when the optical element is a light emitting element, the axis of the light beam incident from the direction perpendicular to the surface 9 does not coincide with the optical fiber axis in the V groove 3. In addition, since the light beam propagating in the optical fiber is reflected at the optical fiber output end, it could not be used for devices and applications that do not like the effect of reflected return light.

Therefore, the technical problem of the present invention has been proposed in view of such problems of the conventional technique, and improves the connection characteristics between an optical fiber and an optical element such as a light emitting / receiving element, and An object of the present invention is to provide a light guide device used for connecting an optical fiber and an optical element, which can reduce the influence of reflected return light by controlling the incident and outgoing angles.

[0005]

[Means for Solving the Problems]

 According to the present invention, the end of the linear light guide member is arranged in the groove formed on the main surface of the silicon single crystal material, and the end surface of the groove on the end surface in the axial direction of the light guide member is arranged. In a light guide device in which opposing surfaces are formed with a reflecting surface that is inclined at a predetermined inclination angle with respect to the axial direction and that faces the main surface side, and the direction of light is changed by reflection on the reflecting surface. A light guide device is obtained in which an end face in the axial direction of the light guide member is inclined with respect to a plane orthogonal to the axial direction at a specific angle determined according to the predetermined inclination angle.

According to the present invention, the silicon single crystal material is made of <111> silicon single crystal, and the groove has a V-shaped cross section formed by anisotropically etching the main surface, A light guide device in which the specific angle is set to 13 degrees can be obtained.

According to the present invention, it is possible to obtain a light guide device in which the predetermined inclination angle is 54.7 degrees and the specific angle is 13 degrees.

That is, specifically, one end face of the optical fiber as the light guide member is inclined in a direction pointing in the same direction as the 13 ° V groove end face with respect to the perpendicular to the optical fiber axis. .

[0009]

[Action]

 In the light guide device of the present invention, the groove which is the light reflecting surface of the silicon single crystal material, and the end face facing the end face in the axial direction of the linear light guide member is inclined at a predetermined angle with respect to the axis line of the light guide member. Even if the light guide member is set at an angle, the end surface of the light guide member is set to incline at a specific angle determined according to the predetermined inclination angle. After hitting the end face of the groove, the light is emitted vertically upward with respect to the axis of this light guide member. Moreover, the reflected return light generated at the time of emission is suppressed to an extremely small level.

[0010]

【Example】

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

FIG. 1 is a sectional view showing a light guide device according to an embodiment of the present invention. FIG. 2 is a sectional view in the direction A of FIG. In FIG. 1, the light guide device optically connects a linear light guide member and an optical element, and a silicon single crystal in which an optical fiber 3 and a V groove 5 for accommodating the optical fiber 3 are formed as the light guide member. Material 1 is provided. An inclined surface 7 which is a light reflecting surface is formed at the terminal end of the V groove 5 so as to face the terminal surface 3a which is the open end surface of the optical fiber 3. The inclination angle of the V-groove termination surface 7 is 54.7 ° with respect to the axis of the optical fiber 3 as in the conventional example. The end surface 3a of the optical fiber 3 housed in the V groove 5 is formed so as to be inclined by 13 ° from the perpendicular to the optical fiber axis in a direction substantially in the same direction as the V groove end surface 7. There is. As a result, the light beam propagating through the optical fiber 3 strikes the V-groove end surface 7, is then refracted by 90 ° with respect to the axis of the optical fiber 3, and is emitted upward. Moreover, since the end face of the optical fiber 3 is formed to be inclined, the reflected return light generated at the time of emission is suppressed to an extremely small level.

FIG. 3 shows an example in which an optical element 4 such as a PIN photodiode connected to the optical fiber 3 is mounted. The optical element 4 will be described as a light receiving element for convenience of explanation. As can be seen from this figure, the light emitted from the optical fiber 3 and reflected by the V-groove termination surface 7 reaches the light receiving element 4 perpendicularly to the axis of the optical fiber 3.

[0013]

[Effect of the device]

 As described above, according to the light guide device of the present invention, even in the <111> silicon single crystal material in which the inclination angle of the groove end surface which is the reflection surface can only be set to the predetermined angle (54.7 °). , It enables efficient entry and exit of light rays between the linear light guide member and the optical element.

Moreover, according to the light guide device of the present invention, since the end face of the linear light guide member in the axial direction is inclined at a predetermined angle with respect to the perpendicular to the axis, the light is emitted from the optical fiber. This makes it possible to suppress the return light that occurs when it becomes extremely small, and it is also extremely useful because it can be used for devices and applications that do not like the effects of reflected light.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a light guide device according to an embodiment of the present invention.

FIG. 2 is a sectional view taken in the direction A in FIG.

FIG. 3 is an explanatory diagram showing a state in which an optical element is mounted on the light guide device of FIG.

FIG. 4 is a cross-sectional view showing an example of a conventional light guide device.

[Explanation of symbols]

 1 <111> Silicon single crystal material 3 Optical fiber 3a Optical fiber termination surface 4 Optical element 5 V groove 7 Reflection surface (V groove termination surface) 9 <111> Silicon single crystal material surface

Claims (3)

[Scope of utility model registration request] 1. An end portion of a linear light guide member is arranged in a groove formed on a main surface of a silicon single crystal material, and is opposed to an end surface of the side surface of the groove in the axial direction of the light guide member. In the light guide device, a reflecting surface is formed in the portion to be inclined with a predetermined inclination angle with respect to the axial direction and faces the main surface side, and the direction of light is changed by reflection on the reflecting surface. A light guide device, wherein an end surface of the light guide member in the axial direction is inclined with respect to a plane orthogonal to the axial direction at a specific angle determined according to the predetermined inclination angle. 2. The silicon single crystal material is made of <111> silicon single crystal, the groove has a V-shaped cross section formed by anisotropically etching the main surface, and the specific angle is The light guide device according to claim 1, wherein the light guide device is set at 13 degrees. 3. The light guide device according to claim 1, wherein the predetermined inclination angle is 54.7 degrees, and the specific angle is set to 13 degrees.