JP2578274Y2 - Receptacle type optical module - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a receptacle type optical module, and more particularly to a receptacle type optical module in which internal reflection of the module is suppressed.

[0002]

2. Description of the Related Art Conventionally, this type of receptacle type optical module in which internal reflection is suppressed is a type in which a laser 12 and a photodiode 14 are mounted on a stem 21 and sealed with a microlens cap 15, as shown in FIG. Is inserted into the pipes 13a and 13b and fixed to a receptacle 17 on which an AR (antireflection) coated glass plate 16 is mounted (OQE88-81, Makoto Shimaoka et al., Development of Receptacle Type Laser Module) ). This receptacle type optical module is a glass plate 1 with an AR coat.
The reflection generated at the front end of the optical connector is suppressed by bringing the front end of the optical connector 20 into close contact with 6.

[0003]

In the above-mentioned conventional optical module in which internal reflection is suppressed, an optical semiconductor element sealed in a package is used. Normally, antireflection AR coating is applied to both surfaces of the microlens, which is the reflection surface of the package, according to the wavelength of the optical semiconductor element. Therefore, in order to efficiently suppress the internal reflection of the module, it is necessary to apply the same AR coating as that of the microlens on the glass plate which is the reflection surface of the receptacle portion.

However, the AR coat has a wavelength dependency, and when the optical semiconductor element sealed in the package changes,
The AR coat of the glass plate also needs to be changed, and there is a disadvantage that it lacks versatility.

[0005]

According to the present invention, there is provided a receptacle type optical module for optically coupling an optical fiber and an optical semiconductor element, wherein the optical fiber is fixed to a holder for holding the optical semiconductor element and is fitted with the optical fiber. A receptacle for holding and holding, a glass plate arranged on an optical reference plane in the receptacle, and the optical semiconductor fixed to the glass plate via an optical adhesive between the glass plate and the optical semiconductor element. And a rod lens whose surface on the element side is polished obliquely with respect to the optical axis.

[0006]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.

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

In this embodiment, a receptacle 2 is fixed to a holder 3 for holding an optical semiconductor element 1 and fits and holds an optical connector 8, and a glass plate disposed on an optical reference plane in the receptacle 2. And a rod fixed between the glass plate 5 and the optical semiconductor element 1 via the optical adhesive 10 between the glass plate 5 and the optical semiconductor element 1 and whose surface on the optical semiconductor element 1 side is polished obliquely with respect to the optical axis. Lens 4. That is, the glass plate 5 is fixed to the optical reference surface in the receptacle 2 by the low-melting glass 9. A rod lens 4 whose end surface on the element side is polished obliquely to the optical axis is fixed to the element side of the glass plate 5 via an optical adhesive 10. The package 11 is connected to the fiber 6 of the fitted optical connector 8 and the package 1 via the holder 3.
The optical semiconductor element 1 sealed in the optical element 1 is adjusted so as to be optically coupled, and is fixed to the receptacle 2.

In the receptacle type optical module of this embodiment, when the optical connector 8 having the ferrule 7 whose tip is polished to a convex spherical surface is fitted to the receptacle 2, the ferrule 7
The inner fiber 6 is pressed against the glass plate 5. At this time, the glass plate 5 and the fiber 6 come into close contact with each other, the refractive index is matched, and the reflection is suppressed. The reflection between the rod lens 4 and the glass plate 5 is suppressed by matching the refractive index with the optical adhesive 10. The element-side end surface of the rod lens 4 is processed obliquely with respect to the optical axis to suppress reflected light. The suppression of the reflected light by the oblique polishing is different from the AR coating that reduces the reflection itself, in which the direction of the reflected light is changed so as not to return to the original optical path.
There is no wavelength dependence.

[0010]

As described above, in the receptacle type optical module of the present invention, a glass plate is arranged on the optical reference surface in the receptacle, and the device side end surface is placed on the device side of the glass plate via an optical adhesive. Fixed the rod lens oblique to the optical axis, so that the A was placed on the receptacle part according to the glass surface of the package in which the optical semiconductor element was sealed.
There is no need to apply an R coat. Therefore, since the receptacle portion has no wavelength dependency, there is an effect that it can be applied to optical semiconductor elements of all wavelengths. In addition, there is an effect that the cost can be reduced by sharing parts.

[Brief description of the drawings]

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

FIG. 2 is a cross-sectional view of a conventional receptacle-type optical module in which internal reflection is suppressed.

[Explanation of symbols]

 Reference Signs List 1 optical semiconductor element 2, 17 receptacle 3 holder 4 rod lens 5 glass plate 6, 18 fiber 7, 19 ferrule 8, 20 optical connector 9 low melting point glass 10 optical adhesive 11 package 12 laser 13 pipe 14 photodiode 15 micro lens cap 16 Glass plate with AR coat 21 Stem

Claims (1)

(57) [Scope of request for utility model registration] 1. A receptacle type optical module for optically coupling an optical fiber and an optical semiconductor element, wherein the receptacle is fixed to a holder holding the optical semiconductor element and fits and holds the optical fiber. A glass plate arranged on an optical reference plane in the receptacle,
A rod lens fixed between the glass plate and the optical semiconductor element via an optical adhesive to the glass plate and a surface on the optical semiconductor element side is polished obliquely with respect to an optical axis; A receptacle type optical module characterized by the above-mentioned.