JPH03223801A - Optical waveguide array - Google Patents

Abstract

PURPOSE:To arrange cores at fine pitches by combining specific-pitch projection parts of clads zigzag opposite one another and forming core materials in hollow places formed between the projection parts of both the clad materials. CONSTITUTION:Clad layers 12 with specific thickness T are formed on the surfaces of a base material 11 where recessed parts 11a and projection parts 11b are formed and two base materials in the same shape where clad layers 12 are formed are set opposite each other the projection parts 11b of one base material 11 intrude into the recessed parts 11a of the other base material 11 and the projection parts 11b of both the base materials 11 are arranged zigzag. Core materials having a larger refractive index than the clad layers 12 are injected into the parts surrounded with the clad layers 12 by capillarity of a wiping method to form cores 13. Consequently, the optical waveguide array 10 equipped with the cores 13 at the fine pitches is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an optical waveguide array used in an optical scanning device of an optical printer or the like.

[Conventional technology]

In recent years, optical printers using optical recording devices have appeared in place of line printers that have traditionally been used as output devices for computers.

Such an optical printer is equipped with an optical recording device using a leading waveguide array in which a large number of optical waveguides are arranged in a row.

As a method of manufacturing such an optical waveguide array, there is a known method of arranging optical fibers in a horizontal row and fixing their ends. However, when forming an optical waveguide array by such a method, an extremely large number of extremely thin optical fibers are handled in the process of arranging the optical fibers in an array, which makes the work complicated and poses problems in productivity.

In order to solve this problem, as shown in FIG. 6, a base material 61 in which a large number of concave portions 61a and convex portions 61b are continuously formed and a flat base material 62 are made of a transparent material. The cladding 63 and 64 are formed, and these base materials 61 and 62 are adhered so that the cladding 6364 faces each other.
．． There is a method of filling the void surrounded by the core 65 with the core 65 .

A base material 6 in which such concave portions 161a and convex portions 61b are formed
1 is formed by molding engineered plastic using a molding method such as injection molding, or by etching a metal base material. In addition, the base material on which the cladding is formed is obtained by applying an ultraviolet curable resin to a flat base material, then curing the parts that are desired to be convex parts with UV light through a predetermined photomask, and removing the uncured parts. is also formed.

[Problem to be solved by the invention]

However, the recess 6 is formed in the base material 61 by the method described above.
1a and the convex portion 61b, there was a problem that as the width of the concave portion 61a became smaller, a quadrilateral cross-sectional shape could not be obtained, and the depth of the concave portion 61a could not be increased. That is, the pitch P of the core 65 is 100
The limit is about μm, and in this case the depth d of the core 65 is also 5
It is limited to about 0 μm. This is because the strength of the mold cannot be obtained sufficiently when forming recesses by injection molding, and when manufacturing molds by etching metal materials, if the depth of the recess of the mold is larger than the width of the opening, the recess This is due to the fact that the shape becomes a curved surface. This also applies to the case where etched metal is used as the base material.

Furthermore, even when a recess is formed by exposing an ultraviolet curable resin to a photomask, if the ultraviolet curable resin becomes thick to a certain extent, photopolymerization will not be performed correctly, and the shape of the recess will similarly become a curved surface.

The present invention was made in order to solve the above-mentioned problems, and provides a leading waveguide array with cores arranged at a fine pitch and an optical waveguide array with a core having a vertical width larger than the horizontal width. The purpose is to provide.

[Means to solve the problem]

In order to achieve this object, the leading waveguide array of the present invention forms a cladding material having convex portions projected at a predetermined pitch, and these cladding materials are arranged facing each other so that the convex portions are arranged in a staggered manner. When combined, the core material was formed in the space formed between the convex portions of both cladding materials.

In addition, a cladding material having protrusions projected at a predetermined pitch is formed, and these cladding materials are combined so that the protrusions face each other to form a space between the protrusions, and a core material is inserted into this space. Configured to form.

[Effect]

According to the present invention having the above configuration, two cladding materials having convex portions formed at a predetermined pitch are combined facing each other so that the convex portions are arranged in a staggered manner, and the convex portions of both cladding materials are combined. Since the core is formed within the space formed between the parts, it is possible to provide an optical waveguide array having cores arranged at a fine pitch.

In addition, two claddings each having convex portions formed at a predetermined pitch are combined so that the convex portions face each other to form a space between the convex portions, and since the core portion is formed within this void, the width can be reduced. In contrast, it becomes possible to provide an optical waveguide array having a core with a large vertical width.

〔Example〕

An embodiment embodying the present invention will be described below with reference to the drawings.

FIG. 1 shows a cross section of an optical waveguide array 10 according to the present invention, which includes a base material 11 and a cladding layer 1.
2 and a core 13.

The base material 11 is made of plastic or metal like a conventional optical waveguide, and one side of the base material 11 has many recesses 11.
1a and the convex portion 11b are formed continuously.

A cladding layer 12 having a predetermined thickness T is formed on the surface of the base material 11 on which the concave portions 11a and the convex portions 11b are formed. and,
The optical waveguide array 10 according to the present invention has two base materials 11 of the same shape on which a cladding layer 12 is formed, facing each other, and a convex portion 11 of the other base material 11 is placed in a concave portion 11a of one base material 11.
b enters, and the convex portions 11b of both base materials 11 are arranged in a staggered manner. A core material having a higher refractive index than the cladding layer 12 is injected or injected into a portion surrounded by the cladding layer 12 by capillary action or a wiping method to form a core 13.

A method of manufacturing such an optical waveguide array 1o will be described below.

FIG. 2 shows a cross section of the base material 11 on which the cladding layer 12 is formed. In FIG. 2, a base material 11 on which concave portions 11a and convex portions 11b are formed is formed by molding engineered plastic using a molding method such as injection molding, similar to the conventional manufacturing method of optical waveguide arrays, or by molding a metal material using a molding method such as injection molding. Formed by etching the base material.

The surface of the base material 11 on which the concave portions 11a and the convex portions 11b are formed is coated with a cladding material having a refractive index of 1.5 diluted with a solvent.
The cladding layer 12 is formed by coating the fluororesin with a coating of about 40% and drying it. Also,
The base material on which the cladding is formed can also be formed by applying an ultraviolet curable resin to a flat base material, then curing the part that is desired to be the core with UV light through a predetermined photomask, and removing the uncured part. Ru.

Then, the base materials 11 on which the cladding layers 12 are formed are assembled facing each other so that the convex portions 11b are arranged in a staggered manner. Then, a methacrylic resin monomer having a refractive index of 1.49 is poured into the gap surrounded by the cladding layer 12 and pressed from above and below. Thereafter, the methacrylic resin monomer is polymerized and solidified to form the core 13, which is simultaneously bonded to the cladding layer 12.

Through the above process, the optical waveguide array 10 according to the present invention is formed.

Generally, it is said that it is difficult to make the vertical width of the core of an optical waveguide array larger than the core width. This is because if the vertical width of the core is larger than the horizontal width, the mold used for molding the base material will not have sufficient strength, making it difficult to separate the base material from the mold after molding. When etching a metal material is used as a method, the chemical reaction during etching proceeds anisotropically, so that the cross-sectional shape of the four parts of the mold is not properly quadrilateral, but instead becomes a curved surface.

However, the horizontal width W', vertical width D', and pitch P' of the core 13 of the optical waveguide array 10 according to the present invention are determined using the pitch P1 of the recessed portion of the base material, the depth D, the frontage width W, and the cladding thickness T. Expressing this, W==WP/2-2 T II)'=D P ゛=P/2.

That is, the formed core 13 ideally has a width W'
can be made much smaller than the width W of the recess 11a of the base material 11, and the pitch P'' of the core 13 (approximately 50 μm)
can be made half the pitch P of the recesses 11a of the base material 11, and the vertical width of the core 13 is the same as the depth D of the recesses 11a of the base material 11.

Here, as for the base material 11, the depth D of the recess 11a is 120 μm.
Assume that m1 has a frontage width W of 120 μm, a pitch P of 160 μm, and a thickness T of the cladding layer 12 of 10 μm. At this time, from the above formula, the shape of the core 13 has a width W−
is 20 μm, the vertical width D' is 100 μm, and the pitch P' of :+713 is 80 μm. This is a value that cannot be achieved using conventional optical waveguide array manufacturing methods.

Next, an optical recording device using the optical waveguide array 10 according to the present invention will be explained with reference to FIG.

FIG. 3 shows an optical recording device 30 using an optical waveguide array 10 according to the present invention. In this optical scanning device 30, a light beam emitted from a light source 31 is made into a parallel beam by a collimating lens 32, and then It is deflected at a constant angular velocity by a polygon mirror 33 that rotates at a constant angular velocity.

This deflected light beam is guided to the input end 10a of the optical waveguide array 10 according to the present invention and is incident on the core. The light beam incident on the core is totally reflected at the interface between the core and the cladding, is propagated within the core, is emitted from the output end 10b of the leading waveguide array 10, and travels on the photosensitive drum 34 in a straight line parallel to its rotation axis. scanned at a constant speed.

Each time one line of optical scanning is completed on the photosensitive drum 34, the photosensitive drum 12 is intermittently rotated by a drive source (not shown), and image recording is performed by repeating the optical line scanning.

It should be noted that the present invention is not limited to the embodiments described above, and can be modified as appropriate. For example, in the embodiment described above, the base material 11 on which the cladding layer 12 is formed
The optical waveguide array 10 was formed by combining the
The present invention is not limited to this, and it is also possible to configure the base material and the cladding to be integrally molded using a light-transmitting material such as methacrylic resin (PMMA) by a molding method such as injection molding.

Further, as shown in FIG. 4, two base materials each having a cladding layer 42 formed only on the concave portion 41a of the base material 41 (no cladding on the tip surface of the convex portion 41b) are arranged so that the concave portion and the convex portion engage with each other. It is also possible to manufacture an optical waveguide array.

Furthermore, as shown in FIG. 5, it is also possible to arrange the shallow concave portions 51a and convex portions 5lb of the two base materials 51 to face each other, and form the core 53 in the gap surrounded by the cladding layer 52. It is.

〔Effect of the invention〕

As is clear from the detailed description above, according to the present invention, an optical waveguide array having cores arranged at a fine pitch and an optical waveguide array having cores having a larger vertical width than the horizontal width can be produced at low cost. Moreover, it has the effect of being easily manufactured.

[BRIEF DESCRIPTION OF THE DRAWINGS] FIG. 1 is a sectional view schematically showing an optical waveguide array according to the present invention, FIG. 2 is a sectional view showing a base material on which a cladding is formed,
FIG. 3 is a perspective view schematically showing an optical recording device using an optical waveguide array according to the present invention, FIGS. 4 and 5 are cross-sectional views schematically showing other embodiments of the present invention, and FIG. 6 1 is a cross-sectional view schematically showing a conventional leading waveguide array. 10... Optical waveguide array, 11.41.51... Base material, 11 a, 41 a, 51 a...
Recessed portion, 11b. 41b, 51b... Convex portion, 12, 42.52... Cladding layer, 13.53... Core.

Claims (1)

[Claims] 1. Forming cladding materials having convex portions protruding at a predetermined pitch, combining these cladding materials facing each other so that the convex portions are arranged in a staggered manner, and combining both cladding materials. An optical waveguide array characterized in that a core material is formed in a cavity formed between convex portions of the material. 2. Form a cladding material with protrusions projected at a predetermined pitch, combine these cladding materials so that the protrusions face each other to form a space between the protrusions, and insert the core material into this space. An optical waveguide array characterized by forming an optical waveguide array.