JPH01191809A - Optical parts fixing structure - Google Patents

Abstract

PURPOSE:To suppress the decentering of an optical axis by providing plural screw holes in one line in the axial direction of a lens holder, screwing a screw in this screw hole, pressing a lens and a ferrule against the outside in a cylindrical hole of the lens holder and fixing them. CONSTITUTION:The title structure is provided with a ferrule 14 to which an optical fiber 12 is inserted and fixed, a drum-like lens 16, screws 20, 21, a spacer 22 and an adhesive agent 24 of an epoxy compound. As for a lens holder 10, the center part consists of a hollow cylindrical shape, and four pieces of screw holes 18 which are arranged in one line in the axial direction are provided. To one end of the lens holder 10, the lens 16 is inserted and fixed with the adhesive agent 24, and to the other end, the ferrule 14 is inserted and fixed with the adhesive agent 24. Between the lens 16 and the ferrule 14, the spacer 22 corresponding to a focal distance of the lens 16 is provided. The ferrule 14 is fixed after it is inserted until it runs against the space 22. The screw 21 is screwed into the screw hole the screw hole 18 of the lens holder 10 and the lens 16 is pressed against one side of the lens holder 10 and fixed, and also, the ferrule 14 is pressed in the same direction as the lens 16 and fixed with the screw 20.

Description

[Detailed Description of the Invention] Overview Regarding an optical component fixing structure that fixes a ferrule to which an optical fiber is fixed and a lens to a lens holder, an optical axis misalignment between the ferrule to which an optical fiber is fixed and the lens is minimized. In an optical component fixing structure in which a ferrule with an optical fiber fixed thereto and a lens are inserted and fixed in a cylindrical lens holder, a plurality of screw holes are provided in a row in the axial direction of the lens holder, and screws are inserted into the screw holes. The structure is such that the lens and ferrule are fixed by being screwed in and pressed against one side of the cylindrical hole of the lens holder.

INDUSTRIAL APPLICATION FIELD The present invention relates to an optical component fixing structure for fixing a ferrule to which an optical fiber is fixed and a lens to a lens holder.

When constructing an optical communication system, in addition to an optical transmitter, an optical receiver, and each transmission line, an optical switch, an optical multiplexer/demultiplexer, and various other optical devices are required.

A basic type of optical device is a bulk type in which various optical components are arranged and fixed on a substrate having a flat surface.

In this type of bulk optical device, the relative positional dimensions of the optical component assemblies that require optical axis alignment must be aligned with high precision and fixed on the substrate at the same time. It is also necessary to minimize the optical axis deviation of the optical component itself.

BACKGROUND OF THE INVENTION FIG. 2 shows a cross-sectional view of a conventional optical component fixing structure.

10 is a lens holder, 14 is a ferrule to which the optical fiber 12 is fixed, 16 is a lens, 22 is a spacer, and 24 is an adhesive. The lens holder 10 has a hollow cylindrical shape. A lens 16 is inserted and fixed to one end of the lens holder 10 by an adhesive 24, and a ferrule 14 is inserted and fixed to the other end by an adhesive 24. A spacer 22 corresponding to the focal length of the lens 16 is provided between the lens 16 and the ferrule 14.

When fixing the lens 16 and ferrule 14 to the lens holder 10, in addition to the adhesive 24, soldering, welding, or the like may be used.

According to this fixing structure, the mounting positions of the lens 16 and the ferrule 14 are determined by the spacers 22, and are further fixed completely by the adhesive 24.

Problems to be Solved by the Invention However, in the conventional optical component fixing structure as described above, there is a fitting clearance (backlash) between the external dimensions of the lens and ferrule and the hole diameter of the lens holder. There was a problem in that the center sleeve of the ferrule could be misaligned, increasing initial optical loss. In addition, the size of the backlash may change over time due to creep in the contacting agent application area, solder area, or weld area, and there is a possibility that the increase in optical loss over time may be minimized.

The present invention has been made in view of these points, and its purpose is to provide an optical component fixing structure that minimizes optical axis misalignment between a ferrule to which an optical fiber is fixed and a lens. be.

Means for Solving Problem 1 In an optical component fixing structure in which a lens 16 and a ferrule 14 to which an optical fiber 12 is fixed are inserted and fixed in a cylindrical lens holder 10, a plurality of screws are arranged in a line in the axial direction of the lens holder 10. A hole 18 is provided.

Then, a screw 20121 is screwed into the screw hole 18 so that the lens 16 and the ferrule 14 are pressed against one side of the cylindrical hole of the lens holder 10 and fixed.

Function In the present invention, by screwing the screws 20 and 21 into the screw holes 18 provided in a row in the axial direction of the lens holder 10, the lens 16 and the ferrule 14 are pressed against one side of the cylindrical hole of the lens holder 10. Since the apparent backlash is removed, optical axis misalignment can be reliably prevented.

Embodiments The present invention will be explained in detail below based on embodiments shown in the drawings. Components that are the same as those of the conventional example shown in FIG. 2 will be described with the same reference numerals.

FIG. 1 shows a sectional view of an embodiment of an optical component fixing structure according to the present invention.

14 is a ferrule into which the optical fiber 12 is inserted and fixed;
16 is a drum-shaped lens, 20, 21 is a screw, 22 is a spacer, and 24 is an epoxy adhesive. Reference numeral 10 denotes a lens holder, which has a cylindrical shape with a hollow center, and is further provided with four screw holes 18 arranged in a row in the axial direction. The shape of the lens holder 10 is such that it can be easily machined with high precision and that the shape of the lens 16 and ferrule 1 can be easily processed.
A cylindrical shape is generally used for reasons such as good consistency with 4.

A lens 16 is inserted and fixed to one end of the lens holder 10 with an adhesive 24, and a ferrule 14 is inserted and fixed to the other end of the lens holder 10 with an adhesive 24.

A spacer 22 corresponding to the focal length of the lens 16 is provided between the lens 16 and the ferrule 14. Further, the ferrule 14 is inserted until it abuts against the spacer 22, and then is fixed. Then, a screw 21 is screwed into the screw hole 18 of the lens holder 10 to press and fix the lens 16 to one side of the lens holder 100, and the ferrule 14 is roughly pressed and fixed in the same direction as the lens 16 by the screw 20. .

Heat this assembly to high temperature and apply epoxy adhesive 24.
harden and completely fix.

The optical component fixing structure of this embodiment is used when optical fibers are coupled together as a lens. For example, two optical component fixing structures are mounted facing each other on a substrate, and an optical element such as a filter or prism is inserted between them. This allows it to function as an optical device.

Further, instead of the adhesive 24 used in this embodiment, it is also possible to use solder, welding, or the like for fixing.

Effects of the Invention Since the optical component fixing structure according to the present invention is configured as detailed above, even if there is a fitting clearance (backlash) between the external dimensions of the lens and ferrule and the hole diameter of the lens holder, the ferrule can be fixed. Optical loss can be reduced by keeping the optical axis deviation within the difference between the external dimensions of the lens and the lens. In addition, since the lens and ferrule are pressed against the lens holder with screws and fixed, they are not affected by displacement due to creep of adhesives, etc., minimizing deterioration over time, improving the characteristics and reliability of optical devices. This has the effect of being able to measure the

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of an embodiment of an optical component fixing structure according to the present invention, and FIG. 2 is a cross-sectional view of a conventional optical component fixing structure. DESCRIPTION OF SYMBOLS 10... Lens boulder, 12... Optical fiber, 14... Ferrule, 16... Lens, 18... Screw hole, 20.21... Screw, 22... Spacer, 24... glue. Figure 1: A view of the east side of the Ichito Sugoi row of the Yoshigaku group items set up in the 19th century. Figure 2.

Claims (1)

[Claims] An optical component fixing structure in which a ferrule (14) having an optical fiber (12) fixed thereto and a lens (16) are inserted and fixed in a cylindrical lens holder (10), comprising: Multiple screw holes in a row in the axial direction (1
8), screw the screws (20, 21) into the screw holes (18), and press and fix the lens (16) and ferrule (14) against one side of the cylindrical hole of the lens holder (10). An optical component fixing structure characterized by: