Toppan Printing Co., Ltd.

Toppan Inc.

Jun Onohara

Tomoyuki Shirasaki

Susumu Maniwa

Noriko Kanou

Hironori Nomura

A circuit board having excellent reliability of connection between layers while being capable of achieving a compact and low-profile electronic device. In the circuit board has an LC circuit built therein with the use of a glass core having a through hole, a conductor layer formed in the through hole is connected to a wiring pattern formed on one surface of the glass core, and connected to a wiring pattern formed on the other surface of the glass core, with the conduction layer projected from the surface of the glass core. Thus, the area of contact between the conduction layer and the through hole is increased, thus making it possible to prevent the reliability of connection between layers in the through hole from being decreased, even when the glass core is reduced in thickness for achieving a low-profile device.

Circuit board

A circuit board includes a glass substrate having a first surface and a second surface facing away from the first surface; a first coil wiring pattern formed on the first surface and a second coil wiring pattern formed on the second surface, the first and second coil wiring patterns constituting part of a coil; a through hole extending through a predetermined portion of the glass substrate from an end of the first coil wiring pattern to an end of the second coil wiring pattern; a through hole inner conductive surface formed on the inner side of the through hole, the first and second coil wiring patterns and the through hole inner conductive surface constituting the coil wound around a direction perpendicular to an axis of the through hole and to a direction in which the first and second coil wiring patterns extend.

A circuit board has a glass core in which a through hole is formed, and a conductor pattern is formed on an inner peripheral wall of the through hole and a surface of the glass core to form a circuit element including a solenoid coil element and a capacitor element. Accordingly, a low-cost and compact circuit board capable of supporting high-capacity communication for thin mobile communication devices such as smartphones can be provided. Since the circuit board can be electrically connected to at least one of the electronic components such as a switch, an amplifier, and a filter via one terminal, and can be electrically connected to a mother board via another terminal, it has integrated functions, and can be suitably used for thin mobile communication devices such as smartphones.

Growing community of inventors

Tokyo, Japan

Jun Onohara