JP3177940B2 - Airtight terminal for optical - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an airtight terminal for optically connecting the inside and the outside of an airtight container.

[0002]

2. Description of the Related Art FIG. 3 shows an example of the configuration of a conventional optical hermetic terminal.

As shown in FIG. 3, a conventional optical hermetic terminal has a hole 11 penetrating the inside and outside of the hermetic container,
1, an optical glass 41 of a disk disposed substantially at the center, and O-rings 32 and 33 disposed on both sides of the optical glass;
It comprises hollow O-ring retainers 61 and 62 arranged on both sides of the O-ring, and receptacle collimators 22 and 23 which are respectively fitted to the O-ring retainers and fixed to an airtight container.

By tightly fixing the receptacle collimator to the airtight container, the O-rings 32, 33 are pressed against the optical glass 41 and the inner wall of the hole via the O-ring pressers 61, 62, so that airtightness can be maintained.

Also, receptacle collimators 22, 23
Is emitted from the receptacle collimator as parallel light, and enters the opposing receptacle collimator via the optical glass 41.

[0006]

However, the conventional optical hermetic terminal described above has a structure in which the optical glass 41 is fixed only by the O-rings 32 and 33 on both sides. It is difficult to fix the glass 41 at right angles to the axis of the hole 11.
When the optical glass 41 cannot be fixed at right angles to the axial direction of the hole 11, (1) the collapse of the O-rings 32 and 33 becomes uneven,
Hermetic reliability becomes insufficient. (2) The light emitted from the receptacle collimator 22 or 23 is reflected by the inclined optical glass 41 to increase the light transmission loss. (3) The edge of the optical glass 41 hits the side surface of the hole 11, and the optical glass 41 is broken, thereby deteriorating airtightness and optical transmission loss. There are drawbacks such as.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an optical hermetic terminal for an optical glass between receptacle collimators, which is always arranged at a predetermined position without being changed by the tightening condition at the time of assembly, and which can improve hermetic reliability. Is to provide.

[0008]

In order to achieve the above object, according to the present invention, a pair of receptacle collimators are inserted from opposite sides into a hole penetrating a container , and an optical glass is placed between the receptacle collimators. In an optical hermetic terminal that is arranged and optically couples the inside and the outside of the container, in the middle of the hole, a surface perpendicular to the axis of the hole and protruding inward from the inner peripheral surface of the hole. Have
The optical glass is connected to the receptacle collimator via a sealing member at the step formed as described above.
It is characterized by being further pressed and fixed . In addition, the step
The cylindrical sleeve is inserted into the hole,
It is preferably formed by the end face of the probe.

[0009]

In the optical airtight terminal of the present invention having the above structure, the O-ring is arranged on the step and the optical glass is placed on the O-ring. It is easy to arrange them at right angles, and the airtightness is high and the optical transmission loss is low.

[0010]

FIG. 1 shows an example of an optical hermetic terminal of the present invention. The round hole 10 penetrating the side wall of the container is composed of a large-diameter hole 10a opened inside and a small-diameter hole 10b opened outside. The large-diameter hole 10a and the small-diameter hole 10b are on the same central axis, and a step portion 10c having a surface perpendicular to the axis is formed at the intersection of the different diameters.
The terminal member is mounted in the hole 10 configured as described above as follows.

The large-diameter hole 10a is provided with a step portion 10c and a seal member 31, which is a rubber O-ring in contact with the inner wall surface of the hole, and then the optical glass 41 and a hollow rubber packing 50 are stacked. Has been inserted. The optical glass 41 is a transparent glass disk. further,
A hollow O-ring presser 60 for holding them is mounted and fastened by a bolt. The receptacle collimator 22 is mounted on the O-ring presser 60.

On the other hand, a receptacle collimator 23 on the other side is attached to the small diameter hole 10b. With this configuration, a step 10 c formed at right angles to the axis of the hole 10.
Since the optical glass 41 is attached via the seal member 31 to the optical glass, the optical glass is fixed at a right angle to the optical axis, and stable optical axis coupling is achieved. Further, the pressing force against the seal member 31 is also made uniform in the circumferential direction, so that the sealing member 31 is uniformly compressed over the entire circumference, so that the airtight reliability is improved.

The other embodiment shown in FIG. 2 is different in that the hole 10 penetrates the large diameter hole 10a of FIG. 1 while keeping the same diameter, and the sleeve 12 is inserted to form the step portion 10c. The sleeve 12 is provided with a mounting hole for one of the receptacle collimators 23, and the end surface on the insertion side forms a step 10c.
With such a configuration, the same operation and effect as those of the above-described embodiment can be obtained.

[0014]

According to the present invention, since the positions of the sealing material and the optical glass are determined on the basis of the step of the hole, the optical glass can always be arranged at a position perpendicular to the axial direction of the hole. Further, it is possible to provide an optical airtight terminal having high airtightness and low optical transmission loss.

[Brief description of the drawings]

FIG. 1 is a diagram showing an example of an optical hermetic terminal of the present invention.

FIG. 2 is a view showing another example of the optical hermetic terminal of the present invention.

FIG. 3 is a diagram showing an example of a conventional optical hermetic terminal.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 hole 10a Large diameter hole 10b Small diameter hole 10c Step 22 Receptacle collimator 23 Receptacle collimator 31 Seal member 41 Optical glass 50 Packing 60 O-ring presser

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G02B 6/26-6/34 G02B 6/42-6/43

Claims (2)

(57) [Claims] 1. A pair of receptacle collimators are inserted from opposite sides into a hole passing through a container , and an optical glass is disposed between the receptacle collimators to optically couple the inside and the outside of the container. In the hermetic terminal, in the middle of the hole, perpendicular to the axis of the hole , and
Providing a step formed to have a surface protruding inward from the inner peripheral surface of the hole, pressing the optical glass by a receptacle collimator through a seal member on this step
An airtight terminal for optics characterized by being fixed . 2. The method according to claim 1, wherein the step portion has a cylindrical shape.
An airtight terminal for optical use, characterized in that a sleeve is inserted into the hole and formed by the end face of the sleeve .