JPS6073604A - Photocoupler - Google Patents

Abstract

PURPOSE:To simplify the constitution of a photocoupler by adhering plane sides of two hemispherical lenses with an optical adhesive while a translucent film is interposed and thus forming a spherical lens, and arranging this lens between optical fibers. CONSTITUTION:The plane sides of the two hemispherical lenses 11 and 12 are adhered together with the optical adhesive while the translucent film 13 is interposed to form one spherical lens 10. Light incident from an optical fiber 1 travels straight in the lens 10 partially and is projected from an optical fiber 2 through a spherical lens 20, and the remainder is reflected by the half-mirror made of the translucent film 13 and projected from an optical fiber 3 through a spherical lens 30. The translucent film 13 is formed by vapor-depositing TiO2, SiO2, etc. Consequently, a small-sized, inexpensive coupler is composed of a small number of parts.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an optical coupler (optical device) for coupling optical fibers together.

Traditionally, optical fiber couplers (optical devices) have been of the individual component type as shown schematically in FIG. The optical fiber 2 is connected to the optical fiber 2 which is aligned with the optical fiber 1. On the other hand, the light reflected from the semi-transparent film (half mirror) 7 is converged by a lens 6 and connected to an optical fiber 3 arranged at a constant angle with respect to the optical fiber 1. In the coupler, since the lenses 4, 5.6 and the semi-permeable membrane 7 are each individually constructed, there are many parts, making it difficult to downsize and reduce costs. there were.

Purpose of the Invention An object of the present invention is to provide an optical coupler (optical device) which is small in size and low in cost by minimizing the number of component parts by integrating a semi-transparent membrane and a lens. It is in.

Structure of the Invention In order to achieve the above objects, the present invention provides two
An optical system in which the flat sides of two hemispherical lenses are bonded to each other with a semi-transparent membrane using an optical adhesive to form a spherical lens, and at least one of the pseudo-spherical lenses is arranged between optical fibers. A coupler is provided.

Embodiment of the Invention FIG. 1 schematically shows an embodiment of the invention. The two hemispherical lenses 11 and 12 are bonded to each other with an optical adhesive with their half surfaces sandwiching a semitransparent membrane 13 (half mirror), and are configured like a n1 spherical lens (clo). The semipermeable membrane 13 is made of TiO
, 5in2, etc. is deposited on the flat side of a hemispherical lens, and uses light interference within the thin film to distribute light in a specific wavelength range to a transmitting side and to the opposite side at a predetermined intensity. . In addition, optical adhesives include epoxy resin, acrylic resin, etc. Known resins such as polyester resins can be used.

A lens configured like a spherical lens in this way is described below.
It is called a pseudo-spherical lens 10. This pseudo-spherical lens 10 is placed on the same straight line as the optical fiber, and is placed so that the semi-transparent lens 13 is at a constant angle with respect to the straight line. Further, a spherical lens 20 is placed in contact with the pseudo-spherical lens 10 on the opposite side of the optical fiber on the same line, and an optical fiber 2 is further placed along the same line. Further, a spherical lens 30 is arranged in contact with the pseudo-spherical lens 10 on the light reflection side, and an optical fiber 3 is further arranged along the reflection direction.
is placed.

The light emitted from the optical fiber 1 enters the pseudo spherical lens 10, and the light transmitted through the n1 semi-transparent film 13 enters the spherical lens 20.
After converging at , it is connected to optical fiber 2. Further, the light reflected by the semi-transparent film 13 is converged by the spherical lens 30 and then connected to the optical fiber 3.

FIG. 2 shows another embodiment of the present invention, which is similar in structure to the embodiment shown in FIG.
0.30 is replaced with a pseudo spherical lens 40.50 such as a pseudo spherical lens elO to construct an optical multiplexer/demultiplexer.

This is a filter film 14 formed between pseudo-spherical lenses 10 that transmits light with a wavelength λ1 and reflects light with a wavelength λ2, thereby performing a basic demultiplexing action. Furthermore, in order to improve the filter characteristics, a filter film 14 that transmits light of λl and reflects light of λ3 is provided between the pseudo spherical lenses 40 on the transmission side, and a filter film 14 that transmits light of λ■ and reflects light of λ3 between the reflective pseudo spherical lenses 50. Filter film 4 that reflects light
By forming 3, a higher performance optical demultiplexer can be realized. If the direction of the optical signal is set in the opposite direction, it can also be realized as an optical demultiplexer.

Effects of the Invention According to the present invention, it is possible to provide an optical coupler (optical device) that has a small number of parts, is small, and is inexpensive.

[Brief explanation of drawings]

FIG. 1 is a diagram schematically illustrating one embodiment of an optical coupler (optical device) of the present invention, FIG. 2 is a diagram schematically illustrating another embodiment of the present invention, and FIG. 3 is a diagram schematically illustrating a conventional optical coupler. (Optical device) FIG. 1.2.3...Optical fiber, 10,40.50...
Pseudo-spherical lens, 20.30... Spherical lens, 11°12... Hemisphere lens, 13... Semi-permeable membrane, 14.43
...filter membrane. Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] 1. The planar sides of two hemispherical lenses are bonded to each other with a semi-transparent membrane and an optical adhesive to form a spherical lens, and at least one pseudo-spherical lens is arranged between the optical fibers. Optical coupler.