JPH03164703A - Optical multiplexing/demultiplexing module - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention incorporates a light emitting element and a light receiving element used for bidirectional transmission by transmitting light of different wavelengths on one optical transmission line. This invention relates to an optical multiplexing/demultiplexing module.

[Conventional technology]

A conventional optical multiplexing/demultiplexing module of this type is shown in FIG.

In the figure, (1) is a light emitting element, (2) is a light receiving element, (
3) is an optical fiber terminal, and (4) is a collimating lens that converts the light emitted from the light emitting element (1) into a parallel beam.

(5) is a condensing lens for condensing light onto the light receiving element (2), and (6) is for inputting the light converted into a parallel beam by the collimating lens (4) to the optical fiber terminal (3). .

A common port lens for converting the light emitted from the optical fiber terminal (3) into a parallel beam; (7) is a multilayer dielectric filter; (8) is a multilayer dielectric filter; glass with a multilayer dielectric filter formed on its surface; It is a plate and is installed at an angle of 45 degrees with respect to the optical path connecting the optical fiber terminal (3) and the light emitting element (1).

Next, the operation will be explained. The light with wavelength λ1 emitted from the light emitting element (1) is converted into a parallel light beam by the collimating lens (4), passes through the glass plate (8), and passes through the multilayer film formed on the surface of the glass plate (8). The light enters a dielectric filter (7). Here, a multilayer dielectric filter (7
) transmits light of wavelength λ1, so the parallel light beam of wavelength λ enters the common port lens (6) and is coupled to the optical fiber terminal (3) by the common port lens (6).

On the other hand, the light with wavelength λ2 emitted from the optical fiber terminal (3) is converted into a parallel light beam by the common port lens (6), and then passed through the multilayer dielectric filter (9) formed on the surface of the glass plate (8). incident. Here, since the multilayer dielectric filter (9) reflects the light with the wavelength λ2, the parallel light beam with the wavelength λ2 is reflected in the right angle direction and enters the condenser lens (5). (2) is combined. The coupling between the light emitting element (11) and the optical fiber terminal (3) and the coupling between the optical fiber terminal (3) and the light receiving element (2) are performed via two lenses between the optical paths as described above.

Therefore, in order to efficiently couple the two light emitting elements (1) and the optical fiber terminal (3), each of the two light emitting elements (1), the collimating lens (4), the common port lens (6), and the optical fiber terminal (3) must be The optical axis of the parts must be adjusted and fixed. Similarly, in order to efficiently couple the optical fiber terminal (3) and the light receiving element (2), the optical fiber terminal (3) is required.

The common port lens (6), condensing lens (5), and light receiving element (2) must be aligned and fixed. Further, in the above configuration, a multilayer dielectric filter (7) for separating wavelengths of light is formed on the surface of the glass plate (8), and is installed in the optical path at an angle of 45 degrees.

If the installation angle of this glass plate (8) deviates from the set value.

The angle of the reflected light shifts and the optical path shifts. Therefore, it is necessary to set this glass plate (8) with high precision.

[Problem to be solved by the invention]

Since the conventional optical multiplexing/demultiplexing module is configured as described above, it has the disadvantage that there are many axial alignment adjustment points and it is difficult to assemble the two modules. In addition, a multilayer dielectric filter (8a)
Since the bonding system is sensitive to the inclination of the glass plate (7) on which it is formed, it has the disadvantage of being susceptible to temperature fluctuations, vibrations, shocks, etc. Furthermore, the optical axis of the light receiving element (2) is installed so as to be perpendicular to the optical path connecting the light emitting element (1) and the optical fiber terminal (3).

The light from the light emitting element +11 is scattered by the glass plate (7),
Since the light enters the light receiving element (2) as stray light, there is a drawback that crosstalk increases.

This invention was made to solve the above-mentioned problems by reducing the number of adjustment points for axis alignment, and reducing temperature fluctuations, vibrations, etc.
The object of the present invention is to obtain an optical multiplexing/demultiplexing module that has excellent resistance to environments such as shocks and has little crosstalk.

[Means to solve the problem]

The optical multiplexing/demultiplexing module according to the present invention includes a light emitting element collimator that integrates two light emitting elements and a collimating lens, a common port lens, and a condensing lens, which are inserted and fixed into a through hole provided on the side of a case, and a multilayer film electric conductor filter. A glass block with a pair of parallel sides on which is vapor-deposited is fixed inside a metal case, and the light-receiving element is installed parallel to the optical axis of the light-emitting element collimator and fixed to the metal case via a glass ring. be.

[For production]

In this invention, the optical multiplexing/demultiplexing module has a two-light emitting element collimator, a common port lens, and a condensing lens that are mechanically fitted and fixed into a through hole provided on the side of the case. When manufacturing the terminal part, the light receiving element part, and the light emitting element collimator, it is possible to make three locations: the light emitting element, and the collimator lens part.In addition, a pair of parallel sides with a multilayer film conductor filter deposited on the side surface of the glass block. By fixing the glass block to the reference surface of the case, angular deviation of the reflected light will not occur.In addition, the optical axis from the two light emitting element collimator section to the optical fiber terminal and the multilayer dielectric fiber From the reflection of

〔Example〕

FIG. 1 is a sectional view showing an embodiment of the invention.

In FIG. 1, (1) to (6) are the same as the conventional device described above. (9) is a glass block, and a multilayer dielectric filter (8b) and a reflection mirror αω are formed on the side surface. C1) is a light emitting element collimator.

A light emitting element (1) and a collimator lens (4) are included. ■ is the case, with a light emitting element collimator (
11), the condenser lens (5), and the common port lens (6) are precisely drilled through holes for inserting and fixing them, and are common to the light emitting element collimator (11) and the condenser lens (5), respectively. A port lens (6) is inserted and fixed. (Q is a spacer prism, which is inserted into the gap between the end face of the glass block (9) and the light emitting element collimator 01) and the end face of the condenser lens (5). (b) is a glass ring which holds and fixes the light receiving element (2) and is fixed to the metal case (to). (One is an optical fiber terminal (3
) is a holder that holds and fixes the metal case (■).

Embodiments of the present invention will be described below with reference to the drawings.

A parallel light beam with a wavelength λ□ emitted from the light emitting element collimator 01) passes through the spacerism (1) and enters the multilayer dielectric filter (8b). Here, the multilayer dielectric filter (8b) , because it transmits light.

The parallel light beam of wavelength ^1 passes through the glass block (9), enters the common port lens (6), and is coupled to the optical fiber terminal (3) by the common port lens (6).

On the other hand, the light of wavelength λ2 emitted from the optical fiber terminal (3) is converted into a parallel beam by the common port lens (6).

The light passes through the glass block (9) and enters the multilayer dielectric filter (8b). Here, a multilayer dielectric filter (
8b) reflects the light of wavelength λ2, so the parallel light beam of wavelength λ2 enters the mirror aω formed on the other side of the glass block (9) parallel to this reflecting surface, where it is further reflected and concentrated. The light enters the optical lens (5). Condensing lens (5)
The parallel light flux of wavelength λ2 incident on the light receiving element (2) is coupled to the light receiving element (2) by the condenser lens (5).

As mentioned above, the multilayer dielectric filter (8a) is formed at one end of the parallel side of the glass block (9).

The component of light reflected here is further reflected by the glass block (9)
It is reflected by a mirror α0) formed at the other end of the parallel side surface. The light that entered the glass block (9) in this way is
The light is reflected twice within this glass block (9) and then emitted. Therefore, due to the principle of two mirrors, the glass block (9)
even if it is installed at an angle to the optical path.

The angle of the light emitted from the glass block (9) with respect to the light incident on the glass block (9) does not change. Also.

As shown above, attach the light emitting element collimator to the side wall of the case (
1) Through-holes for inserting and fixing the 994-light lens (5) and the common port lens (6) are pre-drilled with high accuracy, so the 1-light-emitting element collimator co),! The assembly of the optical lens (5), common port lens (6) is completed by simply inserting it into the above-mentioned through hole and fixing it. Therefore, the parts that require optical axis adjustment are the optical fiber end (3) and the light receiving element (2), and the two light emitting element collimator 01) requires the optical axis of the light emitting element (1) and collimating lens (4) to be aligned in advance. Assembly can be completed by simply inserting something into the case ■.

〔Effect of the invention〕

As described above, according to the present invention, the common port lens, the condensing lens, and the light emitting element collimator are simply inserted and fixed into the through hole provided in the side wall of the case, so that assembly is facilitated.

In addition, since we used a glass block with a pair of parallel sides, there was no deterioration in crosstalk due to light diffusion (2
This has the effect of providing a multiplexing/demultiplexing module with good assemblability.

[Brief explanation of the drawing]

FIG. 1 is a sectional top view showing an optical multiplexing/demultiplexing module according to an embodiment of the present invention, and FIG. 2 is a configuration diagram showing a conventional optical multiplexing/demultiplexing module. In the figure, (1) is a light emitting element, (2) is a light receiving element, (
3) C optical fiber terminal, (4) collimating lens, (
51i is a condensing lens, (6) is a common port lens, (7) is a common port lens, and (7) is a common port lens.
) is a glass plate, (8a) and (8b) are multilayer dielectric filters, +911 is a glass block, C0) is a mirror, and C1) is an element collimator. (Noba case, (13a), (13bl is a spacer prism, C4) is a glass ring, (one is a holder. In the two figures, the same reference numerals indicate the same or equivalent parts.

Claims (1)

[Claims] In an optical multiplexing/demultiplexing module that integrates a light emitting element, a light receiving element, and an optical wavelength multiplexing/demultiplexing section, a light emitting element collimator that integrates a light emitting element and a collimating lens for collimating the emitted light of this light emitting element, a light receiving element, and this A condensing lens for coupling light to a light receiving element, an optical fiber terminal, a common port lens for condensing light onto this optical fiber terminal and collimating light emitted from this optical fiber, and a pair of parallel side surfaces. At one end thereof, a multilayer filter for demultiplexing and multiplexing light according to wavelength, at the other end, a glass block equipped with a mirror for reflecting light, and on a side wall, the light emitting element collimator, the condensing lens, and the above. It consists of a case with through holes for inserting and fixing the common port lenses, the glass block is housed in this case, and the light emitting element collimator and the light receiving element are installed and fixed in parallel in the case. An optical multiplexing/demultiplexing module characterized by the following.