GB2331161A

GB2331161A - Optical fibre array block

Info

Publication number: GB2331161A
Application number: GB9823574A
Authority: GB
Inventors: Hyung-Jae Lee; Byong-Gwon You; Tai-Hyung Rhee; Yong-Woo Lee
Original assignee: Samsung Electronics Co Ltd
Current assignee: Samsung Electronics Co Ltd
Priority date: 1997-10-31
Filing date: 1998-10-29
Publication date: 1999-05-12
Anticipated expiration: 2018-10-29
Also published as: CN1218188A; GB2331161B; GB9823574D0; KR19990035461A; KR100277354B1; JPH11231166A; CA2252265C; CA2252265A1

Abstract

An optical fibre array block comprising an optical fibre array having optical fibres, where a predetermined length of the coating of each fibre has been removed, a basic block (120) on which the optical fibre array is mounted, an optical fibre fixing block (110) for fixing the coating-removed portion (100) of the optical fibre array, and epoxy for fixing the coating-removed optical fibre array (100) disposed in a connecting portion (104) of the basic block (120). The basic block comprises (120) a front portion (102), a rear portion (106) and a connecting portion (104). The front portion (102) is coupled to input/output optical waveguides (not shown) of an optical waveguide device and has a groove in which the coating-removed optical fibres (100) are disposed. The rear portion (106) has a groove in which coated optical fibres (130) are disposed and is connected to the front portion (102) by the connecting portion (104). Coating-removed optical fibres (100) are disposed within this connecting portion (104) which has a tapered working area where the width changes from the width of the front portion's groove to the width of the rear portion's groove. The optical fixing block (110) may have an opposite phase to the basic block (120) so that it is suitable for pressing and fixing the optical fibre array on the basic block (120). The basic block (120) and the optical fibre fixing block (110) may be fabricated by wet etching of a silicon crystalline substrate, mechanical work or moulding. Such an optical fibre array block allows optical waveguide devices to be much smaller in size.

Description

OPTICAL FIBER ARRAY BLOCK The present invention relates to an optical fiber array block used in arranging optical fibers on input/output optical waveguides of an integrated optical device for coupling, and more particularly, to an optical fiber array block for miniaturization of an optical waveguide chip.

In a prior art optical fiber array block fabricated for attaching an optical fiber to an optical waveguide device, circular optical fibers are generally fixed using a block having a V-shaped groove. Here, the distance between the respective optical fibers is 250 Hm corresponding to the diameter of a coated optical fiber. In this case, the coating of the optical fibers is removed and then the optical fibers are mounted in the V-shaped groove to a cladding to have a diameter of 125 am.

Generally, in an optical fiber array block, since the distance between optical fibers is 250 um, the distance between waveguides of input/output portions to be coupled to the optical fibers must be 250 um. The optical waveguide device is long, i.e., the length to width ratio is 1000:1. To reduce bending loss in the waveguide, the waveguide must make a smaller transition widthwise than in a traveling direction.

The transition angle of a waveguide is generally less than 1". Thus, in order to fabricate input/output optical waveguides having a gap of 250 2m, a curved waveguide area for connecting the optical waveguide of a main functional portion of a waveguide device and the input/output waveguide is necessary in addition to the main functional portion. Due to addition of the curved waveguide, the length of the optical waveguide device increases drastically as the number of inputs and outputs increases.

According to the invention in a broad aspect, there is provided an optical fiber array block comprising an optical fiber array having optical fibers, a predetermined length of the coating of each optical fiber being removed, a basic block on which the optical fiber array is mounted, an optical fiber fixing block for fixing the coating-removed portion of the optical fiber array, and epoxy for fixing the coating-removed optical fiber array disposed in a connecting portion of the basic block, wherein the basic block comprises a front portion coupled to input/output optical waveguides of an optical waveguide device and having a groove in which the coating-removed optical fibers are disposed, a rear portion having a groove in which coated optical fibers are disposed, and a connecting portion for connecting the front portion and the rear portion, having a tapered structure so that its width changes in the range from the width of the front portion to that of the rear portion, and in which the coatingremoved optical fibers are disposed.

Additional, preferred features of the invention are defined in the claims depending from Claim 1.

It is therefore an advantage of the present invention to provide an optical fiber array block in which optical fibers are arranged without a gap such that the distance between optical fibers of the optical fiber array block is made to be 125 tim corresponding to the diameter of a cladding of an optical fiber, to reduce the chip size of an optical waveguide.

There now follows a description of a preferred embodiment of the invention by way of non-limiting example, with reference being made to the attached drawings in which: FIGs. 1A, 1B and 1C are a plan view, a side view and a front view of an optical fiber array block according to the present invention.

The present invention will now be described in detail with reference to the accompanying drawings. FIGs. 1A, 1B and 1C are a plan view, a side view and a front view of an optical fiber array block according to the present invention, which includes a basic block 120 for mounting optical fibers, optical fibers 100 and 130, an optical fiber fixing block 110 and epoxy 140.

The basic block 120 is a block for mounting an optical fiber array, and includes a front portion 102, a rear portion 106 and a connecting portion 104. The front portion 102 is coupled to input/output optical waveguides of an optical waveguide device (not shown) and has a groove in which the coating-removed optical fibers are disposed. The groove is fabricated to have a width corresponding to the product of 125 (m) which is a cladding diameter of a coating-removed optical fiber and the number of optical fibers to be mounted. The rear portion 106 has a groove in which coated optical fibers are disposed. The groove is fabricated to have a width corresponding to the product of 250 (m) which is the diameter of a coatingcontaining optical fiber and the number of optical fibers to be mounted. The connecting portion 104 connects the front portion 102 and the rear portion 106, and has a tapered structure, that is, its width changes in the range from the width of the front portion 102 to that of the rear portion 106. The coating-removed optical fibers are disposed in the connecting portion 104. In other words, the space between the front portion 102 and the rear portion 106 gently curves in the range from 125 tim corresponding to the width of the front portion 102 to 250 tim corresponding to the width of the rear portion 106, when the optical fibers are mounted on the basic block 120. The length of the connecting portion 104 is appropriately adjusted according to the number of optical fibers to be mounted, so that a great loss due to bending is not generated at the outermost optical fiber having the largest curvature. Generally, the more optical fibers there are to be mounted, the longer the tapering area must be.

According to a preferred embodiment for fabricating the basic block 120 for mounting the optical fibers, a Si crystalline substrate is used. SiO2 or Si3N4 is removed in a strip pattem format, from a (100) Si substrate in which a film-like SiO2 or Si3N4 is formed, and then wet-etched in a KOH solution. In such a manner, the front portion, the rear portion and the tapered area between the front portion and the rear portion can be formed simultaneously. Altematively, the basic block for mounting optical fibers can be fabricated using mechanical work (eg. machining) or molding.

The optical fibers 100 and 130 are mounted in a coated state in the front portion 102 and the connecting portion 104 of the basic block 120, and are used in a coatingremoved state in the rear portion 106 of the basic block 120. It is effective to use ribbon optical fibers for the sake of mounting and using convenience.

The optical fiber fixing block 110 is fabricated such that it sufficiently presses the optical fibers mounted in the front portion 102 of the basic block 120 so as to be capable of fixing the optical fibers. To this end, the optical fiber fixing block 110 is preferably constructed to have an opposite phase of the basic block 120. According to a preferred embodiment, the optical fiber fixing block 110 is fabricated using a wet etching method. Alternatively, the optical fiber fixing block can be formed using mechanical work or molding.

The epoxy 140 fixes the coating-removed optical fiber array positioned in the connecting portion 104 of the basic block 120, and its thickness becomes smaller, going from the front portion 102 to the rear portion 106. Also, the epoxy 140 can fix a predetermined length of the coated optical fiber positioned in the rear portion 106, in addition to the coating-removed optical fiber positioned in the connecting portion 104.

The optical fiber array block is fabricated in sequence by mounting the optical fibers 100 and 130 on the basic block 120, coating the epoxy 140 thereon, and pressing to fix the optical fibers positioned in the front portion 102 of the basic block 120 by the optical fiber fixing block 110. Then, the section of the front portion of the optical fiber array block is polished to then be coupled to the input/output optical waveguide on the chip of the optical waveguide device with low loss.

According to the present invention, the length of a bent optical waveguide area necessary for obtaining the distance of input/output waveguides in a chip of an optical waveguide device can be reduced by reducing the distance between optical fibers by half, that is, from 250 tim to 125 tim, thereby greatly reducing the size of the optical waveguide device.

Claims

CLAIMS 1. An optical fiber array block comprising: an optical fiber array having optical fibers, a predetermined length of the coating of each optical fiber being removed; a basic block on which the optical fiber array is mounted; an optical fiber fixing block for fixing the coating-removed portion of the optical fiber array; and epoxy for fixing the coating-removed optical fiber array disposed in a connecting portion of the basic block, wherein the basic block comprises: a front portion coupled to input/output optical waveguides of an optical waveguide device and having a groove in which the coating-removed optical fibers are disposed; a rear portion having a groove in which coated optical fibers are disposed; and a connecting portion for connecting the front portion and the rear portion, having a tapered structure so that its width changes in the range from the width of the front portion to that of the rear portion, and in which the coating-removed optical fibers are disposed.
2. The optical fiber array block according to claim 1, wherein the optical fiber fixing block has an opposite phase of the basic block so as to be suitable for pressing and fixing the optical fiber array mounted on the basic block.
3. The optical fiber array block according to claim 1 or claim 2, wherein the basic block and the optical fiber fixing block are fabricated using one of wet etching of a silicon crystalline substrate, mechanical work and molding.
4. The optical fiber array block according to any preceding claim, wherein the basic block and the optical fiber fixing block are made of one of silicon, metal and plastic.
5. The optical fiber array block according to claim 1, wherein the basic block is fabricated by removing SiO2 or Si3N4 in a strip pattern format using a (100) silicon crystalline substrate in which a film-like SiO2 or Si3N4 is formed, and then wet-etching in a KOH solution.
6. The optical fiber array block according to any preceding claim, wherein the optical fiber array block is fabricated by the steps of: mounting an optical fiber array on the basic block, coating epoxy thereon, and pressing the optical fiber fixing block to fix the optical fibers disposed in the front portion of the basic block; and polishing the section of the front portion of the basic block of the optical fiber array block to be coupled to the input/output optical waveguides on the chip of the optical fiber device.
7. The optical fiber array block according to any preceding claim, wherein the epoxy fixes the coating-removed optical fiber array disposed at the connecting portion of the basic block and the coated optical fiber of a predetermined length.
8. An optical fiber array block generally as herein described, with reference to and/or as illustrated in the accompanying drawings.