JP2626760B2 - Manufacturing method of optical circuit board - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for manufacturing an optical circuit board used for connecting an optical fiber or a photoelectric element.

(Prior Art) In recent years, optical fibers and photoelectric elements using an optical signal as a control medium have been widely used.

A conventional method for connecting an optical fiber and a photoelectric device will be described with reference to FIGS. 7 and 8. FIG.

FIG. 7 is a block diagram of a conventional light trigger thyristor disclosed in Japanese Patent Publication No. 61-45394. In the figure, an anode electrode 2 and a cathode electrode 3 are fixed to the upper and lower surfaces of a structural body 1 of a light trigger sinostar in which four N-type and P-type semiconductor layers are alternately stacked. A light transmitting plate 5 is provided at a position facing the light receiving surface 4 provided on the n ⁺ layer of the light trigger thyristor main body 1, and irradiates an optical signal transmitted from the optical fiber 6. At the end of the optical fiber 6, a light source 7 for emitting an optical signal is attached.

The operation of the thus configured light trigger thyristor will be described. The optical signal emitted from the light source 7 is
Through the light-transmitting plate 5 from the tip of the light-receiving surface 4
Is irradiated. The thyristor main body 1 is triggered by the irradiation light, and a current flows between the anode electrode 2 and the cathode electrode 3.

In the figure, a ferrule 9 fixed to the tip of the optical fiber 6 is inserted from both ends of the adapter 8 into the optical fiber connector, and a flange formed at the rear end is attached to the adapter 8 via an O-ring 10 by a cap 11. To connect the optical fibers 6 on both sides. The optical fiber 6 is protected from being broken by a pipe 12 inserted into the hole of the ferrule 9.

The operation of such an optical fiber connector will be described. Since the optical fiber 6 is coaxially regulated by the ferrule 9 and the adapter 8, an optical signal propagates through the connection surface.

(Problems to be Solved by the Invention) However, in the case where photoelectric devices such as the optical fiber and the light trigger thyristor described above are mounted on a printed circuit board, each of the photoelectric devices must be connected one by one with an optical fiber. Therefore, there is a problem that wiring is apt to be erroneous, many optical fibers are disturbed, and mass productivity is low.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems, and provides an optical circuit board manufacturing method for accurately and orderly connecting optical fibers and photoelectric elements with high productivity.

(Means for Solving the Problems) In order to solve the above problems, the present invention relates to a method for manufacturing an optical circuit board in which a photoelectric element is mounted on the front surface and an optical path for transmitting an optical signal is formed only on the rear surface. A step of installing a substrate having a through hole between a first mold and a second mold in which a cavity of a predetermined shape for molding an optical path at a predetermined position in advance; And a step of filling the through-hole in the substrate with a light-transmitting resin, and after performing the filling, curing the molten light-transmitting resin, forming an optical path only on the surface opposite to the component mounting surface of the substrate, and The method includes a step of mounting each photoelectric element on the surface opposite to the optical path forming surface and connecting to the optical path on the back surface through the optical path in the through hole.

(Operation) With the above configuration, an optical path can be formed on one side of the substrate by injection molding, and a substrate having the same pattern can be accurately and orderly manufactured with high mass productivity.

(Embodiment) A fourth embodiment of the present invention will be described with reference to FIGS.

FIG. 1 is a cross-sectional view showing a method of manufacturing an optical circuit board according to a first embodiment of the present invention, in which the board is set in a mold.

In FIG. 1, a substrate 13 provided with a through hole 13a is
It is installed in the fixed mold 14 and the movable mold 15. In the fixed mold 14, a cavity 16 and a cavity 17 for forming an optical path are engraved. The cavity 17 has an inclined surface 17a having an angle of 45 °. A cavity 18 for forming an optical path is formed in the movable mold 15 below the through hole 13a of the substrate 13, and is formed in a concave surface so that a convex lens is formed on an end surface of the optical path.
Further, a second sprue 19 is provided on the fixed mold 14,
The gate 20 communicates with the cavity 17.

As described above, when the molten light-transmitting resin is injected into the mold on which the substrate 13 is installed, the molten light-transmitting resin passes through the first sprue and the runner (both not shown) of the mold in order, and the second sprue. The cavity 17 is filled through 19 and the gate 20.
Further, the cavity 18 in the movable mold 15 is filled through the through hole 13a of the substrate 13. The cavity 16 is also filled through another second sprue and another gate (both not shown). After filling, the molten translucent resin cures and forms an optical path on the substrate.

FIG. 2 and FIG. 3 are a cross-sectional view and a rear view showing a state in which a photoelectric element and electronic components are mounted on the optical circuit board manufactured according to the first embodiment.

In FIG. 3, an optical path 21 made of a translucent resin connecting the through holes 13a formed in the substrate 13 is provided on the back surface of the substrate 13.
And 22, optical paths 23 and 24 are formed to be guided from the through hole 13a to the edge of the substrate 13. Optical path 21,2 above
As shown in FIG. 2, the ends of the through holes 13a on the side of the through holes 13a, 23, and 24 have an inclined surface 25 having an angle of 45 ° with respect to the optical axis. Each of the convex lenses 26 is formed. As shown in FIG. 3, a vertical surface 27 perpendicular to the bisecting line of the refraction angle is formed on the outer surface of the bent portion in the optical path 22 that is refracted in the middle.

On the surface of the substrate 13, an optical fiber connector 28 is mounted on the smooth end of the optical path 21, the optical fiber 6 is connected to the optical fiber connector 28, and the light trigger thyristor 29 is mounted on the molded end of the convex lens 26. As described above, the light trigger thyristor 29 includes the main body 1, the anode electrode 2, the cathode electrode 3, the light receiving surface 4, and the light transmitting plate 5.

Further, a light emitting element 30 and a light receiving element 31 are mounted at both ends of the optical path 22. The light receiving element 32 is attached to the end of the through hole of the optical path 23, and the optical fiber 6 is connected to the end of the optical path via an optical fiber connector 33.

The operation of the optical circuit board thus configured will be described. The optical signal that has propagated through the optical fiber 6 enters the optical path 21 via the optical fiber connector 28, and repeatedly reflects on the inclined surface 25 at an angle of 45 ° with respect to the optical axis on the way.
The light reaches the convex lens 26, is condensed, passes through the light transmitting plate 5, and is efficiently irradiated on the light receiving surface 4. The main body 1 is triggered by the irradiation light, and a current flows between the anode electrode 2 and the cathode electrode 3.

The optical signal emitted from the light emitting element 30 enters the optical path 22 and has two inclined planes at the two right angles.
The reflection at the two obtuse bent portions repeats on the vertical surface 27 and reaches the light receiving element 31.

The optical signal emitted from the light emitting element 32 enters the optical path 23, is reflected on the inclined surface 25 on the way, and is transmitted to the optical fiber 6 connected to the optical fiber connector 33.

As described above, according to the present embodiment, the substrate 13 is placed in the molds 14 and 15 and the optical circuit board is manufactured by injection-molding a molten light-transmitting resin, whereby the optical fiber 6 and the photoelectric element are manufactured. Can be accurately and orderly connected with high mass productivity.

Further, since light is converged by the convex lens 26 provided on the end face of the optical path 21, an optical signal can be transmitted to the photoelectric element with high efficiency.

Also, the vertical surface 27 provided outside the bent portion of the optical path 22 reflects light efficiently, so that the optical signal does not attenuate,
A refracted optical path can be formed in a narrow space.

Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 11 is a cross-sectional view of an optical circuit board manufactured according to the second embodiment of the present invention. In the figure, an optical path 34 formed on the surface of a substrate 13 is the same as that of the first embodiment shown in FIG. The difference from the first embodiment is that aluminum or silver reflectors 35 and 36 are deposited on the bottom and outer surfaces of the optical path 34, respectively, or covered by plating. By providing the reflectors 35 and 36 outside the optical path 34, light can be efficiently reflected even in a place where the radius of curvature of the optical path is small, and the reflectors 35 and 36 can be used in an optical path with a small radius of curvature.

Next, a third embodiment of the present invention will be described with reference to FIG. FIG. 13 is a cross-sectional view of an optical circuit board manufactured according to the third embodiment of the present invention. The optical path 37 formed on the surface of the substrate 13 is the same as that of the first embodiment. The difference from the first embodiment is that the outer surface of the optical path 37 is covered with a transparent resin 38 having a different refractive index from the optical path. Accordingly, light can be efficiently reflected even in a place where the radius of curvature of the optical path is small, and therefore, it can be used for an optical path with a small radius of curvature.

Next, a fourth embodiment of the present invention will be described with reference to FIG. FIG. 13 is a sectional view of an optical circuit board manufactured according to the fourth embodiment of the present invention. The optical path 39 formed on the surface of the substrate 13 is the same as that of the first embodiment.
The difference from the configuration of the first embodiment is that the resin 40 that does not transmit light
This is the point that covered the outer surface of the optical path 39. This allows the optical path
No light leaks from 39, and no light enters from outside to cause noise.

In the first embodiment, the cavities 16 and 17 for forming the optical path are formed by engraving the fixed mold 15. However, the cavities 16 and 17 may be formed in the substrate 13 in a groove shape. May be formed.

Further, the substrate 13 may be a substrate on which an electric circuit is formed by a conductor, for example, a copper foil.

(Effects of the Invention) As described above, according to the present invention, an optical path can be formed on one side of a substrate by injection molding, and an optical circuit board having the same pattern can be accurately and orderly produced with high mass productivity. The optical circuit board manufactured by this method can be manufactured, and an optical path is formed only on one side of the board, and a through hole is provided in the board, so that optical connection between the front and back of the board becomes possible, The optical path can be protected from heating when joining the photoelectric element, the photoelectric element, and the component mounted on the surface opposite to the optical path forming surface, and damage to the optical path can be prevented.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a state in which a substrate is set in a mold by a method of manufacturing an optical circuit board according to a first embodiment of the present invention, and FIGS. 2 and 3 are manufactured by using the first embodiment. FIG. 4 is a cross-sectional view and a rear view of an optical circuit board on which photoelectric elements and electronic components are mounted, FIG. 4 is a cross-sectional view of an optical circuit board manufactured in the second embodiment of the present invention, and FIG. FIG. 6 is a cross-sectional view of an optical circuit board manufactured in the fourth embodiment of the present invention, FIG. 7 is a configuration diagram of a conventional optical trigger thyristor, FIG. FIG. 1 is a configuration diagram of a conventional optical fiber connector. DESCRIPTION OF SYMBOLS 1 ... Body, 2 ... Anode electrode, 3 ... Cathode electrode, 4 ... Light receiving surface, 5 ... Translucent plate, 6 ... Optical fiber,
7 ... light source, 8 ... adapter, 9 ... ferrule, 10 ...
... O-ring, 11 ... Cap, 12 ... Pipe, 13 ... Substrate, 13a ... Through hole, 14 ... Fixed mold, 15 ... Movable mold, 16,17,18 ... Cavity, 17a, 25 …… Slope, 19
…… the second sprue, 20 …… gate, 21,22,23,24,34,37,39
…… optical path, 26 …… convex lens, 27 …… vertical plane, 28,33 ……
Optical fiber connector, 29 …… Optical trigger thyristor, 30,3
2 Light-emitting element, 31 Light-receiving element, 35, 36 Reflector, 38
... translucent resin, 40 ... resin that does not transmit light.

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-55-166990 (JP, A) JP-A-55-120004 (JP, A) JP-A-48-92034 (JP, A) 29210 (JP, A) JP-A-61-156204 (JP, A)

Claims (1)

(57) [Claims] 1. A method of manufacturing an optical circuit board having a photoelectric element mounted on a front surface and an optical path for transmitting an optical signal only on a rear surface, comprising a cavity having a predetermined shape for forming an optical path at a predetermined position in advance. Installing a substrate having a through-hole between the molded first mold and the second mold, filling a cavity in each mold and the through-hole of the substrate with a translucent resin, After filling, the molten translucent resin is cured, an optical path is formed only on the surface opposite to the component mounting surface of the board, and each photoelectric element is mounted on the surface opposite to the optical path forming surface, and penetrated A method for manufacturing an optical circuit board, comprising a step of connecting to an optical path on a back surface through an optical path in a hole.