JPH01182806A - Optical communication module - Google Patents

Abstract

PURPOSE:To simplify assembling and adjustment by providing holes crossing at right angles in a hexahedral enclosure formed with two isosceles right-angled triangular prisms and arranging a wavelength filter in this crossing position and fixing converging rod lenses in optimum positions of incidence and emission of a light emitting element, a light receiving element, and a ferrule. CONSTITUTION:Positions of converging rod lenses are so adjusted that optimum coupling states are obtained in respective housings, and they are fixed. A wavelength filter 6 is stuck to the slit part of a triangular prism 2, and faces having longer sides of triangular prisms 1 and 2 are joined to artificially form a hexahedron. Respective housings are fitted to prescribed positions of this hexahedron and are adjusted to an optimum coupling state. Thus, incidence and emission parts and focuses of converging rod lenses are positioned individually, and the adjustment of the optical axis is simplified because axes are determined by cylinder holes.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an optical communication module used for optical wavelength division multiplexing transmission.

BACKGROUND ART FIG. 2 is a diagram showing an example of a conventional optical communication module (bidirectional wavelength division multiplexing transmission), and the figure shows a configuration for transmitting an optical signal of wavelength λ1 and receiving an optical signal of wavelength λ2. It is shown in 7 is a body, 3 is a connector housing, 31 is a ferrule that holds the fiber 33, 41 is a light receiving element, 51
is a light emitting element, 32, 42, and 52 are focusing rod lenses, and 6 is a wavelength filter.

An optical signal with a wavelength λ1 emitted from the light emitting element 51 is converted into a parallel beam by the converging rod lens 52, and is input to the wavelength filter 6. Here, if the wavelength filter 6 is configured to pass the wavelength λ1 and reflect the wavelength λ2, the optical signal of the wavelength λl remains as a parallel beam of light through the focusing rod lens 6.
2, is condensed and coupled to an optical fiber 33. On the other hand, the optical signal of wavelength λ2 emitted from the optical fiber 33 is converted into a parallel light beam by the converging rod lens 32 and input to the wavelength filter 6. As mentioned above, the wavelength filter 6 reflects the wavelength λ2, and the optical axis of the parallel light beam is changed by 90 degrees and is incident on the unidirectional rod lens 42.
The light is focused and coupled to the light receiving element 41.

The method for manufacturing and adjusting the module will be described below.

The connector housing 3, the light-receiving element 41, and the light-emitting element 51 are attached to the body 7, and the convergent rod lens 32.42.52 is fixed at the optimal coupling position of the respective input and output parts. Next, as shown in FIG. 3, a jig for fixing the filter to the support member 61 is inserted into the optical axis intersection of the housing and fixed.

Problems that the invention aims to solve In this conventional example, a light emitting element and a light receiving element are used.

It was difficult to adjust the mounting positions of the ferrule and focusing rod lens and the positions of the three optical axes mentioned above.

Further, the wavelength filter 6 is attached to a support 61 as shown in FIG.
In order to adhere to the surface, precision in angle, tilt, etc. was required.

The present invention has focused on the above-mentioned difficulty in adjustment, and aims to provide an optical communication module suitable for mass production by simplifying adjustment through mechanical precision.

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention provides holes that intersect at right angles in a hexahedral housing formed by two right-angled isosceles triangular prisms in the front of a large surface. A wavelength filter is placed in front of the light emitting element.

A jig with a focusing rod lens fixed at the optimal position for inputting and outputting the light receiving element and the ferrule was manufactured, and this was placed at a predetermined position in the hole in the body to achieve bidirectional optical communication using wavelength multiplexing. It is something to do.

Effects According to the above structure, an optical communication module with a simple structure and easy to manufacture and adjust can be realized, and mass production can be achieved.

Embodiment FIG. 1 is a block diagram showing the configuration of an optical communication module that is an embodiment of the present invention. 1 and 2 are right-angled isosceles triangular prisms (hereinafter abbreviated as triangular prisms), 31 is a ferrule that holds the fiber 33, 3 is a connector housing that accommodates the ferrule 31 and the focusing rod lens 32, and 4 is the light receiving element 41 and the focusing rod lens. 5 is a housing that accommodates the rod lens 42, 5 is a housing that accommodates the light emitting element 51 and the focusing rod lens 52, and 6 is a wavelength filter.

Two cylindrical holes whose axes intersect at right angles are provided on the long side surface of the triangular prism l, and the side walls A and B of each cylindrical hole are machined so that the housings 3 and 4 are precisely fitted. . On the other hand, one cylindrical hole is provided on the long side of the triangular prism 2 so that the axis of the cylindrical hole on the fiber side of the triangular prism 1 coincides with the axis of the cylindrical hole on the fiber side of the triangular prism 1, and a wavelength filter 6 is provided in the slit of the cylindrical hole on the long side. is attached, and the side wall C of the cylindrical hole is machined so that the housing 5 is precisely fitted.

The manufacturing and adjustment method of the module will be described below. The focusing rod lenses 32, 42, and 52 convert the light beam into a parallel light flux, and convert the parallel light flux into a light beam. First, the positions of the focusing rod lenses are adjusted and fixed so that they are optimally coupled in each housing. Next, the wavelength filter 6 is fixed to the slit portion of the triangular prism 2, and the long side surfaces of the triangular prisms 1 and 2 are joined to form a pseudo hexahedron. Each housing is fitted into a predetermined position on this hexahedron and adjusted to an optimal coupling state.

Effects of the Invention According to the present invention, the focal positions of the entrance/exit part and the convergent rod lens can be individually adjusted, and the axis is determined by the cylindrical hole, so that the optical axis adjustment becomes easy. Further, even if the end face of the focusing rod lens is tilted or the wavelength filter is angularly shifted, the optical signal is transmitted using the cylindrical hole, so it is possible to prevent loss from decreasing due to axis shift.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of an optical communication module according to an embodiment of the present invention, and FIGS. 2 and 3 are block diagrams of conventional optical communication modules. 1.2... Right-angled isosceles triangular prism, 3... Connector housing, 4, 5... Housing, 6... Wavelength filter, 31... Ferrule, 33... Fiber, 41
... Light receiving element, 51 ... Light emitting element, 32, 42, 5
2...Focusing rod lens. Name of agent: Patent attorney Toshio Nakao (1 person) Figure 2 Figure 3

Claims (2)

[Claims] (1) A light-emitting element and a light-receiving element are arranged on the side wall of a parallelepiped housing so that their optical axes intersect at right angles in a cylindrical hole inside the housing, and either the light-emitting element or the light-receiving element A ferrule for holding the optical fiber is installed so that the optical axis of the light-emitting element, the light-receiving element, and the ferrule coincide with each other, and converging rod lenses are arranged at the input and output positions of the light-emitting element, the light-receiving element, and the ferrule to form a collimator. An optical communication module characterized in that a wavelength filter is arranged at a position where the optical axis of a collimator intersects and is inclined at 45 degrees with respect to the optical axis so that the input and output light of the light emitting element and the light receiving element is coupled to the optical fiber. . (2) The housing is composed of two right-angled isosceles triangular prisms divided into two by the mounting surface of the wavelength filter, and the light emitting element (or light-receiving element) and ferrule are placed on one of the right-angled isosceles triangular prisms, and the other right-angled isosceles triangular prism is The light according to claim 1, characterized in that a light receiving element (or light emitting element) and a wavelength filter are arranged on an isosceles triangular prism, and two right-angled isosceles triangular prisms are fixed to form a parallelepiped. Communication module.