JPH01219808A - Fiber module for optical communication - Google Patents

Abstract

PURPOSE:To reduce the diameter of a stem by providing a holder on a cap. CONSTITUTION:A holder 5 is fitted on a cap 3 and then the stem 1 requires only area for mounting the cap 3, so that the diameter of the stem 1 is reducible. The fiber module for optical communication is therefore reducible in size on the whole, and the arrangement space for various equipments is reducible. When the holder 5 is fitted on the cap 3, it is important whether or not optical coupling can be secured, but the rigidity of the cap 3 is high, so there is no problem and a laser diode 2 and an optical fiber are aligned with each other easily and speedily with high accuracy.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a fiber module for optical communication that has an optical semiconductor element and optically couples the optical semiconductor element and an optical fiber.

(Prior Art) In recent years, optical communication, which transmits information using light, has come into practical use in various fields.

This optical communication uses an optical semiconductor element such as a laser diode as a light emitting source and an optical fiber as a transmission path, and the optical semiconductor element and the optical fiber are optically coupled by an optical communication fiber module.

A fiber module for optical communication includes a stem, an optical semiconductor element provided on the stem, a cap provided on the stem to cover the optical semiconductor element, and a cap provided at a position optically facing the optical semiconductor element in the cap. A holder is provided on the stem at a position surrounding the cap to hold the end of the optical fiber in optical opposition to the condenser lens.

Note that when attaching the holder to the stem, the optical axes of the optical semiconductor element and the optical fiber are aligned.

(Problem to be Solved by the Invention) Incidentally, in such a fiber module for optical communication, a cap for holding a condensing lens and a holder for holding an optical fiber are both provided on the stem.
This is to maintain the rigidity of the optical coupling to the optical semiconductor element and to prevent optical axis misalignment between the optical semiconductor element and the optical fiber.

However, since the holder is provided at a position surrounding the cap, there is a problem that the diameter of the stem becomes large and the overall shape becomes large.

Further, although the stem L is plated with gold, it may peel off when aligning the optical axis. If this happens, the slippage will deteriorate, making it impossible to perform highly accurate positioning (that is, optical axis alignment).

This invention was made in view of the above circumstances,
The purpose is to reduce the diameter of the stem, thereby making it possible to make the shape more compact, and to enable easy, quick, and highly accurate optical axis alignment of the optical semiconductor element and the optical fiber. The purpose of the present invention is to provide a fiber module for optical communication.

A stem, an optical semiconductor element provided on the stem, a cap provided on the stem to cover the optical semiconductor element, and a cap provided at a position optically facing the optical semiconductor element in the cap. and a holder provided on the cap to hold the end of the optical fiber optically opposed to the condenser lens.

(Function) By providing a holder on the cap, the diameter of the stem can be reduced.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

In Figures 1 and 2, 1 is a disc-shaped stem;
An optical semiconductor element such as a laser diode (LD) 2 is provided at the center of the upper surface of the stem 1 . Further, a cap 3 is provided on the stem 1 so as to cover the laser diode 2.

The cap 3 is made of a highly rigid material.

Further, the center portion of the cap 3 is penetrated vertically, and a spherical condensing lens 4 is fixed thereto. This condensing lens 4
is located at a position optically facing the laser diode 2, and serves to focus the laser light emitted from the laser diode 2 to one point above.

Thus, a holder 5 is provided on the cap 3. This holder 5 holds the end (incidence end) 6a of the optical fiber 6 so as to optically face the condensing point of the condensing lens 4, and the flange 5a at the lower edge is attached to the upper surface of the cap 3. It is attached by YAG laser beam welding.

Here, when attaching the holder 5 to the cap 3, pressure is applied by the pressure lever 7 so that there is no gap between the lower surface of the flange portion 5a and the upper surface of the cap 3, and so that the holder 5 does not move. , in that state stem 1
By moving the laser diode 2 and the optical fiber 6
Optical axis alignment (optical axis A) is performed. Then, welding with the YAG laser beam is performed with the optical axis alignment completed.

Furthermore, the pressurization of the pressure lever 7 prevents displacement during welding.

In addition, the optical axis alignment is performed on the other end side (light receiving side) of the optical fiber 6.
The process is completed by attaching a light-receiving element to the light-receiving element and moving the stem 1 to a position where the amount of light received by the light-receiving element is maximized.

By attaching the holder 5 on the cap 3 in this manner, the stem 1 only needs to have an area large enough to place the cap 3, and the diameter of the stem 1 can be reduced. Therefore, the overall shape of the optical communication fiber module can be reduced, and the installation space in various devices can be reduced.

In particular, when attaching the holder 5 to the cap 3, there is a concern about whether optical coupling can be secured, but since the cap 3 is made of high rigidity, there is no such concern at all, and the laser diode 2 and the optical fiber 6 can be easily, quickly, and highly precisely aligned. Moreover, no optical axis deviation occurs after coupling. Furthermore, the gold plating on the stem 1 will not peel off.

It should be noted that the present invention is not limited to the above embodiments, and can be applied not only to light emitting systems but also to light receiving systems.

[Effects of the Invention] As described above, according to the present invention, there is provided a stem, an optical semiconductor element provided on the stem, a cap provided on the stem to cover the optical semiconductor element, and a cap provided on the stem to cover the optical semiconductor element. A condensing lens provided on the cap at a position optically facing the optical semiconductor element, and a holder provided on the cap and holding an end of the optical fiber optically facing the condensing lens. This makes it possible to reduce the diameter of the stem, which makes it possible to make the shape more compact, and also enables easy, quick, and highly accurate alignment of optical axes between optical semiconductor elements and optical fibers. We can provide fiber modules.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the internal structure of an embodiment of the present invention, and FIG. 2 is an external perspective view of the embodiment. DESCRIPTION OF SYMBOLS 1... Stem, 2... Laser diode (optical semiconductor element), 3... Cap, 4... Condensing lens, 5...
...Holder, 6...Optical fiber. Applicant's agent Patent attorney Takehiko Suzue Figure 1 tJ2

Claims (1)

[Claims] A stem, an optical semiconductor element provided on the stem, a cap provided on the stem to cover the optical semiconductor element, and a cap provided at a position optically facing the optical semiconductor element in the cap. 1. A fiber module for optical communication, comprising: a condensing lens; and a holder provided on the cap to hold an end of an optical fiber optically facing the condensing lens.