Hitachi, Ltd.

Noriaki Ujiie

Yasuhiko Hara

Koichi Karasaki

Osamu Yamada

Akira Sase

Hideyasu Murooka

Masayuki Kyooi

A method and an apparatus of forming a multilayer printed circuit board which can positively remove voids in the prepregs in the printed board and enhance the reliability of the produced printed circuit board and is superior in economy, wherein a laminated assembly of a plurality of printed circuit board components and a plurality of prepregs alternately laminated on each other is sandwiched between upper and lower jig plates, and the laminated assembly sandwiched between the jig plates is clamped between heating plates of a bonding press to heat the assembly to a predetermined temperature, and, thereafter, a pressure is applied to the upper and lower jig plates so as to urge them against each other for bonding the printed circuit board component and the prepregs. An exterior pressurizing means is provided around the printed circuit board components and the prepregs sandwiched between the upper and lower jig plates in order to prevent the molten prepregs from flowing outwardly, thereby raising the fluid pressure of the molten prepregs to squeeze out air bubbles existing in the prepregs.

Method of forming a multilayer printed circuit board and apparatus

Method and apparatus for detecting wiring patterns wherein a printed circuit board is irradiated with a light ray which excites a substrate of the printed circuit board to generate a fluorescent radiation from the substrate, the fluorescent radiation generated from portions other than a wiring pattern of the printed circuit board is imaged by means of an image detector, and a negative pattern of the wiring pattern is detected on the basis of an image signal generated from the image detector.

Method and apparatus for detecting wiring patterns

A pattern detecting apparatus for inspecting a printed wiring board is disclosed in which a fluorescent image formed by the fluorescent light from the substrate of the printed wiring board and an image formed by the reflected light from the wiring pattern of the printed wiring board are both used because a wiring material which is left on an undesired portion of the substrate and has low reflectivity, is detected only at the fluorescent image and a defective portion of the wiring pattern where a surface layer thereof peels off, is detected only at the image formed by the reflected light, the image used for detecting the above defective portion is preferably formed by the reflected infrared light from the wiring pattern for the reason that infrared light is insensitive to a shallow flaw in the surface of the wiring pattern, and the fluorescent image and the infrared image are processed by a detection circuit, and then compared with each other to detect a pattern defect on the basis of a difference between the images thus processed.

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Hadano, Japan

Noriaki Ujiie