JPS6179290A - Light/electron printed substrate - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a printed circuit board on which electronic circuit elements are mounted to configure an electronic circuit.

(Prior Art) Printed circuit boards are generally used to mount electronic circuit elements and combine them to form a desired electronic circuit. Conventional printed circuit boards simply have conductor patterns for electronic circuits on one or both sides of the base, and in the case of multilayers, between each layer as well, for conducting current or potential.

(Problems to be Solved by the Invention) Conventional printed circuit boards can only configure electronic circuits. Therefore, in order to prevent noise or to transmit and receive signals between insulated circuits, it is necessary to insert an optical element such as a photocoupler.

The present invention allows not only electronic circuits to be built on a single printed circuit board, but also
It is an object of the present invention to provide a printed circuit board that can also constitute an optical circuit.

(Means for Solving the Problems) The printed circuit board of the present invention not only includes at least one conductive pattern similar to a conventional printed circuit board for configuring an electronic circuit, but also has The device further includes an optical waveguide embedded in the base.

(Function) The conductor pattern is used to configure an electronic circuit, the optical waveguide is used to form an optical circuit, and both the electronic circuit and the optical circuit are formed on one printed circuit board.

(Example) Fig. 1 shows an example, and Fig. 1 (A) is a perspective view of the main part.
The figure (B) is a sectional view taken along the line AB of the figure (A).

2 is a base material such as a glass epoxy plate that is generally used as a base for a printed circuit board, and 4 is a cladding material formed on the base material 2. A wire rod 6 having a circular cross section and made of a highly transparent material is embedded in the clad material 4. The wire 6 is made of a material with a higher refractive index than the cladding material 4, and the wire 6 functions as the core of the optical waveguide.

The wire rod 6 is made of, for example, PMMA (polymethyl methacrylate) resin, and the clad material 4 is made of, for example, fluororesin.

A plate material in which the base material 2 and the cladding material 4 are integrated serves as the base of the printed circuit board of this embodiment, and copper foil patterns 8 and 10 for configuring electronic circuits are formed on the front and back surfaces of the board, similar to a general printed circuit board. has been done. Reference numeral 12 denotes a device hole for mounting an element, and the end surface of the wire 6 is exposed on the wall of the device hole. 14 is a through hole.

The wire 6 is not limited to being made of an organic polymer material such as PMMA resin, but may also be made of quartz glass. The cladding material 4 can also be formed of a material other than fluororesin.

The printed circuit board of this embodiment can not only mount elements for electronic circuits such as ICs and individual electronic components like a general printed circuit board, but also a light emitting element such as a light emitting diode, a light receiving element such as a phototransistor, or a light receiving element such as a phototransistor. It is also possible to mount an element including such an optical element. for example,
As shown in FIGS. 2(A) and 2(B), an element 16 including such an optical element is inserted in a state where it is partially buried in the device hole 12, and the light emitting part of the element 16 is inserted. Or the wire 6 with the light receiving part 18 exposed on the wall of the device hole 12
By fixing the light emitting section or the light receiving section 18 so as to face the end face of the waveguide, the light emitting section or the light receiving section 18 and the leading waveguide can be easily coupled with good adhesion.

Next, a number of embodiments and their manufacturing methods will be shown in FIGS. 3 to 6.

FIG. 3 is the same as the embodiment shown in FIG. 1, and in order to manufacture it, a glass epoxy plate 3 is placed on which base material 2 the wire 6 that will become the core of the optical waveguide is placed. Then, pour the cladding material 4 into a plate shape from above and form the wire material 6.
Embed. After curing the cladding material 4, the base material 2
Copper foil is pasted on both or one side of a plate material made of cladding material 4 as a base, and etching is performed to form a pattern 8.10 for an electronic circuit, and device holes and through holes are formed as necessary. .

In the embodiment shown in FIG. 4, a groove 20 is formed in the base material 2 by means such as photo-etching, and after the wire rod 6 serving as the core is placed in the groove 20, a high The wire rod 6 is embedded in the clad material by pouring the molecular material 22 and curing it. Thereafter, electronic circuit patterns 8 and 10 are formed in the same manner as in FIG.

In the embodiment shown in FIG. 5, after first hardening the cladding material 4 into a plate shape on the base material 2, grooves 24 are formed in the cladding material 4 by means such as photo-etching, and the grooves 24 are formed in the same way as in FIG. The wire rod 6 is placed in the wire rod 6, and the cladding material 22 is poured and hardened to embed the wire rod 6, and then the electronic circuit pattern 8.1 is embedded.
0 is formed.

In the embodiment shown in FIG. 6, a wire 6 is embedded in a cladding material 4 to form the core of the optical waveguide, and base materials 2-1, 2-2 are provided on both sides of the cladding material 4 to form a sandwich structure. was formed. Such a structure has the advantage of high mechanical strength. In this case as well, the electronic circuit pattern 8,1° is formed in the same manner.

Further, the present invention can be applied to a printed circuit board having a multilayer structure, in which case the base material 2.2-1 or 2-2 has a multilayer structure and is also provided with an electronic circuit pattern inside.

FIG. 7 shows an example of the terminal portion of the printed circuit board of the present invention, which is provided with a plurality of terminals 24 to be connected to a connector like a general printed circuit board, and the end surface has a wire of an optical waveguide embedded therein. The end face 26 is exposed.

In this terminal portion, in order to prevent the light from the end surface 26 of the wire 6 from being diverged, the end surface 26 is, for example, the eighth
It is preferable to have a convex shape as shown in the figure. Here, 4 is a cladding material, 2 is a base material, and 24 is a terminal. More preferably, the end surface 26 is located inside the end surfaces of the cladding material 4 and the base material 2, as shown in FIG. Here, 28 is a sleeve that protects the end surface 26 of the wire 6, and prevents the wire end surface 26 from being covered by the cladding material.

This structure of the wire end surface 26 is applied in exactly the same way to the wire end surface exposed in the device hole 12 shown in FIG.

(Effects of the Invention) By using the printed circuit board of the present invention, it is possible to assemble both an optical circuit and an electronic circuit on the same board, thereby making it possible to create a circuit that is resistant to noise.

Furthermore, it becomes possible to realize a one-board microcomputer that uses optical waveguides in circuits for data transfer among the circuits that make up the computer, so it becomes possible to increase the data transfer speed. Furthermore, since data can be transferred simultaneously to a large number of independent arithmetic circuits, it is suitable for application to parallel processing type or non-Neumann processing type computers.

[Brief explanation of the drawing]

1(A) and 1(B) are perspective views of essential parts and cross-sectional views taken along the line A-B showing one embodiment of the present invention, and FIGS. 2(A) and 2(B) show elements of the same embodiment. 3 to 6 are partial sectional views each showing an embodiment, and FIG. 7 is a partial perspective view showing a terminal portion of one embodiment. 8 and 9 are partial cross-sectional views of a printed circuit board showing preferred examples of wire end faces, respectively. 2... Base material, 4... Clad material, 6... Wire material forming the core of the optical waveguide, 8.10
...Electronic circuit pattern.

Claims (1)

[Claims] (1) An optical/electronic printed circuit board comprising at least one layer of a conductor pattern for an electronic circuit and an optical waveguide embedded in a base on which the conductor pattern is formed.