Abstract: A circuit board includes: a metallic plate having an opening; a flexible circuit board disposed on a first surface of the metallic plate; and a printed circuit board disposed in the opening of the metallic plate. The flexible circuit board is protruded to the opening of the metallic plate so that a part of the flexible circuit board is bonded to the printed circuit board. The printed circuit board includes a first land disposed on a first surface of the printed circuit board, which is disposed on the first surface of the metallic plate. The flexible circuit board includes a second land disposed on a first surface of the flexible circuit board, which is opposite to the metallic plate. The first and second lands are electrically connected each other with a connecting member.

Abstract: A circuit board includes: a metallic plate having an opening; a flexible circuit board disposed on a first surface of the metallic plate; and a printed circuit board disposed in the opening of the metallic plate. The flexible circuit board is protruded to the opening of the metallic plate so that a part of the flexible circuit board is bonded to the printed circuit board. The printed circuit board includes a first land disposed on a first surface of the printed circuit board, which is disposed on the first surface of the metallic plate. The flexible circuit board includes a second land disposed on a first surface of the flexible circuit board, which is opposite to the metallic plate. The first and second lands are electrically connected each other with a connecting member.

Abstract: A method of manufacturing a back light type display panel includes a first step of forming on a transparent base film an opaque area of a thick layer of toner particles and a transparent area of a thin layer of toner particles, a second step of covering the opaque and transparent areas of the base film with a transparent protection film. In this step, a thermoplastic adhesive agent is coated on the protection film to form a laminate member of thick and thin layers of toner and the protection film. The method further includes a third step of vacuuming the laminate member and its surrounding, and a fourth step of heating the laminate member to be lower for the toner to melt and sufficiently high for the adhesive agent to have a characteristic of tack and pressing the laminate member at a first pressure by a pair of pressing boards, and a fifth step of heating the laminate member to be sufficiently high for the toner to melt.

Abstract: A printed circuit board, having a plurality of via-holes provided in an area where circuit elements are arranged, includes a thermally conductive material having thermally good conductivity, for example copper, and the thermally good conductive material is formed in an inner wall of each of the plurality of via-holes. Each of the plurality of via-holes has, for example, a circular shape, and is arranged in the form of hexagonal or triangular lattice in the area where the circuit elements are arranged. Further, preferably, a diameter of each of the plurality of via-holes is equal to a hole pitch having an allowance .+-.0.3 mm. According to above structure, it is possible to provide a plurality of via-holes per unit area with high density on the printed circuit board and to improve the thermal conductivity of the printed circuit board by effectively radiating the heat generated from the circuit elements.