JP2001296436A - Method for manufacturing optical circuit board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing an optical circuit board with which wiring and connecting of an optical fiber are carried out with high precision. SOLUTION: A film shaped base material in which a base film, an adhesive layer and a releasing sheet are laminated in this order is prepared. In the film shaped base material, a slit which penetrates from the surface of the releasing sheet to the base film is provided in a place used as the taking-out end of the optical fiber in the contour of the optical circuit board to be formed. Further, a notched groove having such a depth that the releasing sheet is completely penetrated, but the base film is not penetrated is formed so as to be connected to both ends of the slit along the contour of the optical circuit plate. The releasing sheet is peeled along the notched groove and the adhesive layer is exposed. The optical fiber is laid on the exposed adhesive layer so that the end of the optical fiber extends up to on the releasing sheet. Finally, the part excepting the slit of the contour of the optical circuit plate is cut and processed, and the optical circuit plate is cut off from the film shaped base material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an optical circuit board in which optical fibers are laid and fixed in a circuit on a substrate.

[0002]

2. Description of the Related Art An optical fiber is used for communication using light having a very high frequency as a carrier wave, and has been developed as a communication medium capable of performing high-quality transmission with little loss when transmitting a signal to a long distance. In addition to transmission of optical signals, there are a wide variety of uses such as transmission of energy and images, optical sensors, and the like. Optical fibers have excellent properties such as low loss, wide band, light weight, flexibility, and environmental resistance.

Originally, the optical fiber was originally developed for long-distance communication. However, in recent years, it has been proposed to use a conductive wire having a small amount of information for short-distance communication or transmission inside a device. Have been.

[0004] For example, Japanese Patent Application Laid-Open No. 61-186908 discloses a communication system and a measurement system that perform mutual conversion between light and electrons. In this system,
Three or more substrates having an optically active device, an optically passive device, and a drive circuit for driving the optically active device are laminated, and an optical fiber layer is inserted between the laminated substrates. The optical fiber couples elements of different substrate layers to form an optical circuit. The optical fiber layer connecting the elements is formed by embedding two optical fibers in a UV resin substrate at intervals of 2 mm so as to partially cross each other. The intersection of the optical fibers functions as an optical splitter / coupler.

Japanese Patent Application Laid-Open No. 1-180505 discloses a method of forming an optical circuit in which an optical fiber as an optical waveguide is laid on a substrate via an adhesive layer. In this method, an optical fiber is laid directly on an acrylic adhesive layer formed on an ABS resin substrate using a fiber laying tool.

Further, in Japanese Patent Application Laid-Open No. 1-183605, the end of an optical fiber is fixed to a waveguide array, and this waveguide array is fixed on an optical circuit board on which a light receiving element is mounted via a support base. . An end surface of the waveguide array is an inclined surface, and a condenser lens is provided on the inclined surface to reflect and condense input light from the optical fiber to a light receiving element on a circuit board.

[0007]

SUMMARY OF THE INVENTION Incidentally, Japanese Patent Application Laid-open No. Sho 61
As disclosed in JP-A-186908, in a communication system or a measurement system that performs mutual conversion between light and electrons, an optically active element, an optically passive element, and a drive circuit for driving the optically active element are provided on the substrate of each layer. When the optical circuit is formed between the substrates by stacking three or more layers of these substrates, the thickness of the entire substrate increases. Further, in the optical fiber layer, it is difficult to take out the connection end of the optical fiber from the UV resin layer. Furthermore, if any failure occurs in the optical circuit, all the board parts including the electronic circuit must be replaced, which is economically disadvantageous.

In this method, since there is a large gap between the alignment accuracy required for optical interconnection and the accuracy of electrically mounting an optical element or the like, the accuracy gap is absorbed in the optical interconnection part. Need room to do so. As a result, the size of the substrate is inevitably increased, which is far from practical.

On the other hand, the method disclosed in Japanese Patent Application Laid-Open No. 1-180505 is economical because only the optical circuit is independent and laid by a tool. However, in this method, all parts of the optical fiber are fixed to the adhesive on the substrate, and stress is left on the optical fiber during the laying process.
The stress in the optical fiber is gradually released, and as a result,
There is a possibility that the optical fiber partially peels off from the adhesive layer and eventually comes off the substrate. In addition, in order to extract a signal from the optical circuit, it is necessary to peel off that part and process and form a signal extraction end, and there is a problem that the optical fiber is easily damaged at that time.

In the configuration described in Japanese Patent Application Laid-Open No. 1-183605, light from an optical fiber is condensed by a condensing lens provided on an inclined end surface of a waveguide array supported by a support table above an optical circuit board. The light is focused on the upper light receiving element. However, in this configuration, when the inclination angle of the end face of the waveguide array is reduced, the fixing position of the optical fiber must be lowered, and assembling and handling of the substrate become difficult. There is a problem of becoming high.

SUMMARY OF THE INVENTION An object of the present invention is to provide a simple method of manufacturing an optical circuit board that can accurately join an optical fiber to an optical element and can reduce the size.

[0012]

In order to achieve the above object, an optical circuit board manufacturing method according to the present invention comprises a film state in which a base film, an adhesive layer, and a release sheet are laminated in this order. Prepare a substrate. In this film-like base material, a slit is formed in the contour of the optical circuit board to be formed, at a position corresponding to an edge serving as a take-out end of the optical fiber, from the surface of the release sheet to the base film. Furthermore, along the contour of the optical circuit board, a cut groove of a depth that completely penetrates the release sheet but does not penetrate the base film,
It is formed so as to be connected to both ends of the slit. The release sheet is peeled off along the cut grooves to expose the adhesive layer. The optical fiber is laid on the exposed adhesive layer so that the end of the optical fiber extends to the remaining release sheet. Finally, a portion of the contour of the optical circuit board other than the slit is subjected to a cutting process, and the optical circuit board is separated from the film-like base material.

For the film-like substrate, it is preferable to use an adhesive layer that is tacky at room temperature for simplifying the optical circuit manufacturing process and for simplifying the processing. Further, when laying the optical fiber on the adhesive layer, a numerically controlled wiring machine is used. The slit and the cut groove are preferably formed by using a laser processing method. The step of separating the optical circuit from the substrate on the film is also preferably performed using a laser processing method. Cutting and cutting operations by a laser processing method are performed using a laser processing machine based on layout data of an optical circuit board.

According to the method of the present invention, a slit is formed in advance at a position corresponding to the take-out edge of the optical fiber connection end of the optical circuit board, and the end of the optical fiber is taken out. Since the taken out optical fiber connection end is temporarily disposed on a portion other than the adhesive layer, the optical fiber connection end does not inadvertently adhere to the adhesive layer. Further, when the optical fiber is finally cut into the shape of the optical circuit board, the optical fiber is not damaged. Due to these characteristics, the method of the present invention is particularly effective when a flat cable is formed by combining a plurality of optical fibers inside or at the end of an optical circuit board.

[0015] Other features and advantages of the present invention will become more apparent from the detailed description given below with reference to the accompanying drawings.

[0016]

FIG. 1 shows an optical circuit board 1 manufactured by an optical circuit board manufacturing method according to an embodiment of the present invention.
FIG. FIG. 1B is a plan view showing a wiring layout of the optical circuit board 10, and FIG. 1A is a plan view of FIG.
3 is a cross-sectional view taken along line AA of FIG.

In this embodiment, the optical circuit board 10 has a contour 8
And has three protruding portions as a portion for taking out the optical fiber to the outside of the circuit. However, such a shape is merely an example, and various shapes can be taken according to the design. it can.

The optical circuit board 10 includes a film-like base material 3 composed of a base film 1 and an adhesive layer 2, an optical fiber 4 laid on the surface of the adhesive layer 2, and an optical fiber 4 and an adhesive layer 2. And a cover film 5 covering the entire surface. The cover film 5 functions as a protective film for the optical fiber 4. In this optical circuit board 10, the end of the optical fiber 4 sandwiched between the cover film 5 and the adhesive layer 2 extends from the side end surface of the optical circuit board 10 to the outside.

The optical circuit board 10 also has one or more hollow windows 6 therein, and the end of the optical fiber 4 is connected to the hollow window 6.
Extends from the side end surface of the inside of the window 6. For example, an optical element such as a light receiving element is installed inside the hollow window. In that case, the connection end of the optical fiber extending inside from the side end surface of the hollow window is connected to the optical element.

Film-like substrate 3 on which optical fiber 4 is mounted
It is desirable that the material has good dimensional stability and flexibility.
In order for the film substrate 3 to have such characteristics, it is efficient that the base film 1 has such characteristics. The base film 1 is, for example, a heat-resistant, flame-retardant polyimide film or a polyethylene terephthalate (PET) film used for a flexible wiring board. In addition, among those obtained by press-molding a glass epoxy prepreg reinforced with a glass cloth usually used for a printed circuit board, one having a thickness of about 0.1 mm may be used.

The adhesive layer 2 on the base film 1 is an adhesive layer having tackiness at room temperature in consideration of the simplicity of the manufacturing process and the like. For example, polyisobutylene, acrylonitrile butadiene rubber, or crosulfonated polyethylene is preferably used as the adhesive material.

Further, as the adhesive layer 2, an adhesive layer of a double-sided pressure-sensitive adhesive tape can be used. In this case, the manufacturing and processing steps are further simplified as described later.

As the optical fiber 4 wired on the adhesive layer 2, a communication optical fiber can be used. The optical fiber may be glass (quartz) or plastic. As the cover film 5 for protecting the optical fiber 4, the same film as that of the base film 1 such as PET or polyimide can be used. Further, in order to secure air permeability, a mesh-like or porous film is covered with a cover film 5.
It is preferably used. By using a mesh or porous film, the adhesive layer 2 and the cover film 5
Air bubbles can be prevented from being trapped at the interface. If air bubbles are trapped at the interface in the cover sheet bonding process, the cover sheet 5 or the optical fiber 4 is peeled off due to the expansion of the air bubbles when the optical circuit board is processed and used at a high temperature. Further, the circuit board itself may be deformed. As the mesh film, a polyester mesh can be used.

FIG. 2 is a view showing a manufacturing process of the optical circuit board 10 shown in FIG.

(A) First, as shown in FIG. 2A, a film-like base material 13 with a release sheet (release carrier) 7
Prepare The film-shaped base material 13 further includes a release sheet 7 on the adhesive layer 2 of the film-shaped base material 1 shown in FIG.

The adhesive layer 2 preferably has tackiness at room temperature. This is because an extra step such as a heating step can be eliminated, and the manufacturing process of the optical circuit can be simplified. As the adhesive material, for example, polyisobutylene, acrylonitrile butadiene rubber, or crosulfonated polyethylene can be used. The adhesive layer 2 is formed by dissolving these materials in a solvent, directly applying them on the base film 1 and drying them. If necessary, a crosslinking agent may be added to these materials. The release sheet 7 is stuck on the adhesive layer 2 thus formed. In the case where the adhesive layer 2 is continuously applied to the base film 1 wound in a roll and dried, the release sheet 7 may be pasted immediately before the base film 1 is wound again into the roll. Conversely, an adhesive material dissolved with a solvent is directly applied on the release surface of the release sheet 7,
After drying and forming the adhesive layer 2, the base film 1 may be bonded onto the adhesive layer 2.

As the release sheet 7, a double-sided release paper used for a general double-sided tape, a release-treated film used for an adhesive tape, or the like can be used. For example,
A polyethylene terephthalate (PET) film subjected to a release treatment is suitably used in the method of the present invention.

(B) Next, as shown in FIG. 2 (b), a slit 9
Insert In FIG. 2B, for convenience of explanation, the outline 8 of the optical circuit board is shown by a dotted line on the surface of the film-like base material 13; Does not appear on the base material 13. The slit 9 serving as the extraction end of the optical fiber 5 is
0 based on the design layout.

The slit 9 is formed as shown in FIG.
It is completely cut from the release sheet 7 to the base film 1. FIG. 2C is a cross-sectional view along the line BB of FIG. 2B. As a method for forming the slit 9, cutting by a cutter or cutting by pressing a metal cutting die prepared in advance into a desired shape can be considered, but an NC (numerical control) driven laser processing machine is used. The method is preferred because it allows accurate work with only data preparation.

(C) Next, as shown in FIG. 2D, cut grooves 11 are formed in the release sheet 7 along the contour 8 of the optical circuit board 10. In the present embodiment, the cut grooves 11
Is formed somewhat outside the outline 8 of the optical circuit board 10, but may be formed along the outline 8. When the cut groove 11 is formed slightly outside the contour 8, the release sheet 7 is not left in the optical circuit board 10 when the film substrate 13 is finally cut into the shape of the optical circuit board. Yes.

The cut groove 11 completely separates the release sheet 7 from the surface of the release sheet 7.
It is stopped at a depth that does not separate it. In the present embodiment, as shown in FIG. 2E, the cut groove 11 having a depth reaching the adhesive layer 2 is formed. In addition, FIG.
FIG. 3 is a cross-sectional view taken along the line CC of FIG. The reason for forming such cut grooves 11 is to enable the release sheet 7 to be easily peeled along the shape of the fiber mounting area of the optical circuit board 8 in the next step. Therefore, it is preferable that the cut groove 11 is formed so as to be connected to or close to both ends of the slit 9 serving as an optical fiber take-out end.

(D) Next, as shown in FIG. 3A, the release sheet is peeled off along the cut grooves 11 and the optical circuit 1 is removed.
In the region where the optical fiber mounting surface of the
To expose. FIG. 3A shows a step that follows the step shown in FIG. As a result, the release sheet 7 remains in a region where the optical fiber 4 is not fixed, and the adhesive layer 2 is exposed only in a region necessary for mounting the optical fiber. Since the optical circuit board of this embodiment has a hollow window 6 for mounting an optical element therein, the release sheet 7 also remains at a portion corresponding to the hollow window 6. Such a method facilitates handling of the film-shaped substrate 13 particularly when the adhesive layer 2 has high tackiness. Further, it is possible to prevent the take-out end of the optical fiber 4 from sticking to the adhesive surface.

(E) Next, as shown in FIG. 3B, an optical fiber 4 is laid in the optical fiber mounting area. It is preferable to use a numerically controlled wiring machine for laying the optical fiber. At this time, when the optical fiber is laid on the adhesive layer 2, by applying a load and vibration by ultrasonic waves to the optical fiber, the adhesive force can be further increased. As such an apparatus, for example, a wiring machine for multi-wire wiring disclosed in Japanese Patent Publication No. 50-9346 can be used. Any optical fiber can be used.For example, when laying a multimode optical fiber made of quartz, use a Corning 50/125
CPC6, GI-50 / 125, QSI-85 / 125, SI-8 manufactured by Hitachi Cable, Ltd.
5/150 or the like can be used, and when setting a single mode optical fiber, SM-10 / 125 manufactured by Hitachi Cable, Ltd. can be used. When laying a plastic optical fiber, for example, a Reitera PF manufactured by Toray Industries, Inc.
U, Esca series manufactured by Mitsubishi Rayon Co., and Luminous manufactured by Asahi Kasei Co., Ltd. can be used.

When the optical fiber is laid, if the optical fiber is sharply or sharply bent, the optical fiber is easily broken. In addition, there is a problem that light transmitted through the optical fiber leaks to the outside or light is attenuated when the optical fiber is stressed. Further, if the optical fiber is broken or the stress remains locally, it causes distortion of the optical circuit board in a later process. In order to prevent these problems, it is preferable to lay the optical fiber in a curved shape or an arc shape. Optical fibers may cross over the adhesive layer 2 depending on the design of the optical circuit. In this case, by stopping at least one of the load and the ultrasonic vibration applied to the optical fiber near the intersection, the stress on the optical fiber can be reduced, and the optical fiber can be prevented from being damaged.

FIG. 3C is a sectional view taken along the line DD of FIG. 3B, and shows a state in which the optical fiber 4 is set on the adhesive layer 2. The optical fiber 4 has passed over the slit 9 serving as a take-out end of the optical fiber, and has terminated on a region where the release sheet 7 is left. As described above, the optical fiber 4 can be effectively prevented from sticking to the adhesive layer 2 in an unnecessary area, and the handling in the subsequent process can be simplified.

(F) Next, as shown in FIG. 3D, a cover film 5 is provided to cover the optical fiber 4 and the adhesive layer 2. The cover film 5 is preferably processed into a shape of an optical fiber mounting area in advance, and is preferably a mesh or porous film. In this case, when the mesh or porous film is adhered to the adhesive layer 2 by applying a slight pressure, the air trapped at the interface is removed, and the cover film 5 is adhered to the adhesive layer 2. Can be done. When a uniform film is used, a vacuum state is applied before the cover film 5 comes into close contact with the adhesive layer 2 using a vacuum laminating apparatus. Thereafter, by performing pressure bonding at a low pressure, it is possible to eliminate bubbles trapped at the interface without leaving a large stress. If air is trapped at the interface and closed cells remain, it expands in a high-temperature use environment,
This may cause distortion of the optical circuit board and deterioration of accuracy. Attempts to remove air bubbles with a high-pressure press exert the disadvantage that excessive force is applied to the optical fiber 4 and the light is greatly attenuated. In addition, a large force is locally applied at the intersection of the optical fibers 4 and may be damaged. There is. Therefore, in the present embodiment, as described above, the cover film 5 made of a porous film is adhered on the adhesive layer 2 to protect the optical fiber 4. When a mesh film is used as the cover film, for example, a polyester mesh TB-70 manufactured by Tokyo Screen Co., Ltd. can be used. Examples of the porous film include Duragard manufactured by Celanese Corporation and Celgard 2400 manufactured by Daicel Chemical Industries, Ltd.

(G) Finally, as shown in FIG.
The film-shaped substrate 13 is cut along the contour 10 of the optical circuit board 10. This process can also be performed with a cutter knife or a blade. However, it is desirable to use an NC drive laser beam machine, since the end face of the optical circuit board can be accurately processed only by preparing data. At this time, the portion where the slit 9 is provided earlier has already been cut at a previously designed position, and the end of the optical fiber 4 is extended.
The end face is processed avoiding this part. When the cut groove 11 is formed along the contour 8 of the optical circuit board 10, the cutting is performed along the cut groove 11. When the cut groove 11 is formed slightly outside the outline 8 of the optical circuit board 10,
Since it is cut off by the end face processing of FIG. 3E, it does not affect the final optical circuit board 10.

According to such an optical circuit board manufacturing method,
In the manufacturing process of the optical circuit, it is possible to effectively prevent the take-out end of the optical fiber from being adhered to an unnecessary area, and to form a circuit wiring accurately without damaging the optical fiber.

When an optical element circuit board is formed by using the optical circuit board 10 of the present invention, for example, a connector, a light receiving element, an optical active element and the like are arranged around the optical circuit board 10 and inside the hollow window 6. Then, an optical fiber extending from the side end surface of the optical circuit board 10 can be connected to these optical elements. Since the end of the optical fiber 4 protrudes from the side end surface of the optical circuit board 10 in advance, it is not necessary to perform a processing for taking out the optical fiber, and the optical fiber is not unnecessarily damaged.

The method of the present invention is particularly effective when it is necessary to collectively lower a plurality of optical fibers inside or at the end of an optical circuit board into a flat cable shape. In the conventional method, the optical fiber must be taken out after laying the optical fiber in the adhesive layer and pasting the cover film, but in the method of the present invention, before cutting the optical circuit board, Since the optical fiber is taken out at the location, damage to the optical fiber can be avoided.

(Example) The base film 1 of the film-like base material 13 was a polyimide film having a thickness of 50 μm.
Was roll-laminated with a 250 μm-thick VBH A-10 film as an adhesive tape with a release sheet having a thickness of 250 μm. The adhesive layer of the VBH A-10 film is tacky at room temperature. By bonding this to Kapton 200H, the adhesive layer 2 and the release sheet 7 were formed on the base film 1. Next, a slit 9 was provided at a predetermined position of the film-shaped base material 13 by using a laser beam machine used for forming a small-diameter hole in the printed circuit board. More precisely, a pulse width of 5 ms and φ0.2 for 3 shots
Were moved at intervals of 0.1 mm, processed into a desired shape, and slitted.

Further, with this laser beam machine, a pulse width of 5
The holes having a diameter of 0.2 were moved at intervals of 0.1 mm along the contour of the optical circuit board with a shot number of 1 ms and the cut grooves 11 were formed in a desired shape. As a result, only the release sheet 7 in the optical fiber mounting area can be peeled off. The release sheet in this area was peeled off, and an optical fiber was laid using a multi-wire wiring machine. The used multi-wire wiring machine is a wiring machine capable of controlling output of ultrasonic vibration and load, and capable of driving an XY table by NC control. Multimode optical fiber GI-50 / 125 (outside diameter 250μm)
Was laid. At the time of laying, the optical fiber was subjected to a load of 100 g and ultrasonic vibration having a frequency of 25 kHz. The optical fiber was laid in an arc shape, and the load and the ultrasonic vibration were temporarily stopped near the intersection of the optical fibers. The optical fiber take-out end led eight optical fibers together at a pitch of 260 μm to the outside of the part to be an optical circuit board so as to form a flat cable.

The same polyimide film as the base film 1, that is, Kapton 200H manufactured by DuPont was used as a cover sheet for protecting the optical fiber, and the cover sheet was laminated on the adhesive layer on which the optical fiber was laid by vacuum lamination.

Using the above-described laser drilling machine, a hole of φ0.2 with a pulse width of 5 ms and four shots is moved at intervals of 0.1 mm along the contour of the optical circuit board and processed into a desired shape. Cut. At this time, the laser processing performed along the cut groove 11 is not performed on the slit portion for taking out the eight optical fiber ends that are put together in the flat cable shape, and the laser processing performed along the cut groove 11 is connected to both ends of the slit. The cutting process was performed as follows. By such a cutting process, the portion where the release sheet was left was removed, and the optical circuit board was completed. The eight cables arranged in a flat cable shape were exposed at a length of 10 mm from the end face of the optical circuit board.

In the optical circuit board manufactured in this manner, no breakage of the optical fiber was observed in the entire portion where the optical fiber was laid, particularly in the wiring portion where the optical fiber crossed. Except for the interface where the optical fiber having a circular cross section was located, no closed cells remained inside the circuit board.

[0046]

As described above, according to the method of manufacturing an optical circuit of the present invention, an optical circuit board can be manufactured with a simple process and with high accuracy without damaging an optical fiber. Further, the connection end for connecting the optical fiber to the optical element can be accurately and easily taken out. Further, the remaining air bubbles in the circuit board can be removed.

[Brief description of the drawings]

FIG. 1 is a diagram of an optical circuit board according to an embodiment of the present invention. FIG. 1 (b) is a top view of the optical circuit board, and FIG. 1 (b) is FIG.
It is sectional drawing which followed the AA line of (a).

FIG. 2 is a view showing a manufacturing process of an optical circuit board manufacturing method according to one embodiment of the present invention.

FIG. 3 is a view showing a process of forming an optical circuit board subsequent to the process shown in FIG. 2;

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 base film 2 adhesive layer 3, 13 film-like base material 4 optical fiber 5 cover film 6 hollow window 7 release sheet 8 optical circuit board contour 9 slit 11 cut groove

Continued on the front page (72) Inventor Yuichi Shimayama 1500 Ogawa, Shimodate-shi, Ibaraki F-term in Hitachi Chemical Co., Ltd. Research Laboratory

Claims (8)

[Claims] 1. A step of preparing a film-like base material in which a base film, an adhesive layer, and a release sheet are laminated in this order, wherein the film-like base material has an outline of an optical circuit board to be formed. Providing a slit that penetrates from the surface of the release sheet to the base film at a location to be the takeout end of the optical fiber, and completely penetrates the release sheet along the contour of the optical circuit board, Forming a cut groove having a depth not penetrating the film so as to be connected to both ends of the slit; peeling the release sheet along the cut groove to expose an adhesive layer; and exposing the exposed adhesive layer. Laying the optical fiber so that the end of the optical fiber extends on the release sheet from which the end of the optical fiber has not been peeled off; the exposed surface of the adhesive layer; and the surface of the adhesive layer. Covering the laid optical fiber, comprising the steps of: providing a cover film, the slit cut processing a contour portion excluding the method for manufacturing an optical circuit board including the steps of cutting the optical circuit board from the film-shaped substrate. 2. The step of preparing the film-like substrate,
The method for manufacturing an optical circuit board according to claim 1, wherein an adhesive having room temperature is used as the adhesive layer. 3. The method according to claim 1, wherein in the step of laying the optical fiber, the optical fiber is laid using a wiring machine controlled numerically. 4. The method of manufacturing an optical circuit board according to claim 1, wherein said slit forming step uses a laser processing method. 5. The method of manufacturing an optical circuit board according to claim 1, wherein the step of forming the cut groove uses a laser processing method. 6. The method of manufacturing an optical circuit board according to claim 1, wherein in the step of forming the cut groove, the cut groove is formed slightly outside the contour. 7. The method of manufacturing an optical circuit board according to claim 1, wherein said cutting step uses a laser beam machine. 8. The method according to claim 1, wherein at least one of the slit forming step, the cut groove forming step, and the cutting processing step is performed based on layout data of an optical circuit board. The method for producing the optical circuit board described in the above.