Abstract: Multilayer printed wiring boards may be prepared by forming a via hole by laser irradiation in insulating layer formed by a prepreg, comprised of a glass cloth impregnated with a thermosetting resin composition, and subjecting the via hole to a glass etching treatment with a glass etching solution and then to a desmear treatment with an oxidizing agent solution. By such a process, etch back phenomenon and excessive protrusion of glass cloth from the wall surface of a via hole can be sufficiently suppressed, and a highly reliable via can be formed. Particularly, a highly reliable via can be formed in a small via hole having a top diameter of 75 ?m or below.

Abstract: Multilayer printed wiring boards may be prepared by forming a via hole by laser irradiation in insulating layer formed by a prepreg, comprised of a glass cloth impregnated with a thermosetting resin composition, and subjecting the via hole to a glass etching treatment with a glass etching solution and then to a desmear treatment with an oxidizing agent solution. By such a process, etch back phenomenon and excessive protrusion of glass cloth from the wall surface of a via hole can be sufficiently suppressed, and a highly reliable via can be formed. Particularly, a highly reliable via can be formed in a small via hole having a top diameter of 75 ?m or below.

Abstract: A plastic optical element for use in an optical scanning device including light effective portions that focus light, and at least one link portion that connects the light effective portions in the sub-scanning direction, the link portion forming a border arc having a curvature radius R of 2 mm or greater and contacting the light effective portions such that the tangent of the light effective portion at the connection point of the light effective portion and the border arc matches the tangent of the border arc at the connection point.

Abstract: Multi-layer printed wiring boards may be produced by: (1) conveying an adhesive sheet from an adhesive sheet roll wherein an adhesive sheet having a prepreg formed on a support film is wound in a roll and placing the adhesive sheet such that a prepreg surface contacts one or both of the surfaces of a circuit board, (2) partially adhering the adhesive sheet to the circuit board by heating and pressing a part of the adhesive sheet from the support film side, and cutting the adhesive sheet according to the size of the circuit board with a cutter, (3) heating and pressing the temporarily fitted adhesive sheet under reduced pressure to laminate the adhesive sheet on the circuit board, (4) forming an insulating layer by thermally curing the prepreg, and (5) detaching the support film after the thermal curing step.

Abstract: A plastic optical element for an optical system of an optical scanner includes a plurality of optical effective portions through which a plurality of light beams transmit, respectively, formed on at least one of an incidence surface and an exit surface in a sub scan direction, and an optical ineffective portion formed between neighboring optical effective portions not to allow the light beams to transmit therethrough, and including an area in which a local contraction occurs at a time of resin molding.

Abstract: A production method of a multi-layer printed wiring board containing the following steps (1)-(5): (1) a temporary fitting preparatory step including conveying an adhesive sheet from an adhesive sheet roll wherein an adhesive sheet having a prepreg formed on a support film is wound in a roll and placing the adhesive sheet such that a prepreg surface contacts one or both of the surfaces of a circuit board, (2) a temporary fitting step for temporarily fitting the adhesive sheet to the circuit board, including partially adhering the adhesive sheet to the circuit board by heating and pressing a part of the adhesive sheet from the support film side, and cutting the adhesive sheet according to the size of the circuit board with a cutter, (3) a laminating step including heating and pressing the temporarily fitted adhesive sheet under reduced pressure to laminate the adhesive sheet on the circuit board, (4) a thermal curing step including forming an insulating layer by thermally curing the prepreg, and (5) a detachin

Abstract: An optical scanning device that scans a plurality of surfaces to be scanned in a main scanning direction by using a light beam includes: a plurality of light sources; a light deflector that deflects a plurality of light beams emitted from the light sources; and a scanning optical system that individually guides each one of the light beams deflected by the light deflector to a corresponding one of the surfaces to be scanned. The scanning optical system includes one scanning lens shared by the light beams, and at least one surface of the scanning lens has a plurality of optical surfaces corresponding to the plurality of light beams disposed in a sub-scanning direction with a flat surface provided between the optical surfaces.

Abstract: A resin casting mold includes a mold member forming a cavity that includes first and second surfaces facing each other in a first direction. The mold member further includes an insert member which forms a part of a third surface and which is slidable in a second direction perpendicular to the first direction. At least one cross-sectional shape of the cavity satisfies h<A<H, where “A” is the length of the insert member in the first direction, “h” is a spacing in the first direction between a portion of the first surface closest to the insert member and a portion of the second surface closet to the insert member, and “H” is the length in the first direction on the third surface. The insert member is disposed to include a region having the spacing “h”.

Abstract: A plastic article is formable by using a metal die having a cavity to accommodate melted resin therein at a given pressure. The plastic article includes a transfer face to which is transferred a face shape of the metal die, a projection disposed at least one face other than the transfer face, an incomplete transfer face having a concave shape disposed at the same face on which the projection is disposed, formed by an incomplete transfer of a face shape of the cavity of the metal die, and an incomplete transfer face having a convex shape disposed at least one face other than the transfer face.

Abstract: A first plastic lens and a second plastic lens constituting each imaging optical system are arranged on opposite sides of an optical deflector, so that main scanning directions of optical beams scanned by the single optical deflector become substantially parallel to each other, and the first plastic lens and the second plastic lens of at least one of the plurality of (four) imaging optical systems are formed such that secondary components at scanning positions on the (four) surfaces to be scanned are arranged in a same direction, and are molded by a same mold cavity.

Abstract: A plastic optical element for focusing light to a target includes a first lens and a second lens. The first lens includes an incident surface, a projection surface opposite the incident surface, and a non-optical surface through which light does not pass and that includes a non-transfer portion. At least one light beam passes from the incident surface to the projection surface. The second lens includes an incident surface, a projection surface opposite the incident surface, and a non-optical surface through which light does not pass and that includes a non-transfer portion disposed opposite the non-optical surface of the first lens. At least one light beam passes from the incident surface to the projection surface. The non-transfer portions of the first lens and the second lens are portions on which no surface is transferred from a surface of a mold used to form the plastic optical element.

Abstract: An optical scanning device for guiding a light beam to a member to scan the member with the light beam, including a light source emitting the light beam; a light deflector deflecting the light beam; a focusing optical system including a plastic optical element molded using a die. The optical element has least two transfer surfaces formed by contacting with transfer surfaces of the die and including a light entrance surface and a light exit surface; and a third surface including a non-transfer surface formed without contacting a transfer surface of the die. The light beam passes through the optical element in such a manner that the optical axis center of the light beam extends in a direction parallel to the shorter side of the optical element while being shifted from the dimensional center of the optical element toward the third surface of the optical element.

Abstract: A plastic optical element for guiding a scanned light beam in a main scanning direction and a sub-scanning direction, which is prepared by a molding method using a die. The element includes: a main body including at least two optically functional surfaces, which are transfer surfaces formed by contacted with transfer surfaces of the die and through which the light beam passes; and at least two ribs located on surfaces of the main body other than the optically functional surfaces and extending in parallel in the main scanning direction. A recessed portion is present on a surface of at least one of the ribs, and the recessed portion has a side transfer surface and a bottom surface, which is a non-transfer surface, and the distance between the optically functional surfaces is less than the length of the main body in the sub-scanning direction.

Abstract: A molded plastic part prepared by injecting a resin in a cavity of a die so that a pressure is generated in the resin in the cavity and at least one transfer wall surface of the cavity is transferred to the resin. The plastic part has at least one transferred surface; at least one imperfectly transferred concave portion on a first surface thereof other than the transferred surface; and at least one imperfectly transferred convex portion on the first surface or a second surface thereof other than the transferred surface. The ratio (a)/(b) of the thickness (a) of the plastic part in a direction perpendicular to the transferred surface to the thickness (b) of the plastic part in a direction parallel to the transferred surface is less than 1.

Abstract: A plastic optical element for use in an optical scanning device including light effective portions that focus light, and at least one link portion that connects the light effective portions in the sub-scanning direction, the link portion forming a border arc having a curvature radius R of 2 mm or greater and contacting the light effective portions such that the tangent of the light effective portion at the connection point of the light effective portion and the border arc matches the tangent of the border arc at the connection point.

Abstract: A plastic optical element is provided, which includes an optical element body having a transfer surface which includes at least one laser beam incident portion of a concave shape, and a support portion connected with the optical element body, in which the support portion is disposed in a direction of a tangent line at an end of the transfer surface, and the optical element body and a part of the support portion are molded in the same nest structure.

Abstract: An optical element having an optical surface and at least three convex portions on a surface different from the optical surface, wherein, among the at least three convex portions, two convex portions a space between whose centers is a maximum and one convex portion a length of a perpendicular from whose center to a straight line connecting centers of the two convex portions is a maximum satisfy a relationship of tan?1 (h/p)?a first specification value, wherein h is a greater one of heights of the optical element at centers of the two convex portions with reference to a tangential plane of the optical element at a position of a foot of the perpendicular, and p is a length of the perpendicular.

Abstract: A production method of a multi-layer printed wiring board containing the following steps (1)-(5): (1) a temporary fitting preparatory step including conveying an adhesive sheet from an adhesive sheet roll wherein an adhesive sheet having a prepreg formed on a support film is wound in a roll and placing the adhesive sheet such that a prepreg surface contacts one or both of the surfaces of a circuit board, (2) a temporary fitting step for temporarily fitting the adhesive sheet to the circuit board, including partially adhering the adhesive sheet to the circuit board by heating and pressing a part of the adhesive sheet from the support film side, and cutting the adhesive sheet according to the size of the circuit board with a cutter, (3) a laminating step including heating and pressing the temporarily fitted adhesive sheet under reduced pressure to laminate the adhesive sheet on the circuit board, (4) a thermal curing step including forming an insulating layer by thermally curing the prepreg, and (5) a detachin

Abstract: A plastic optical element for guiding a scanned light beam in a main scanning direction and a sub-scanning direction, which is prepared by a molding method using a die. The element includes: a main body including at least two optically functional surfaces, which are transfer surfaces formed by contacted with transfer surfaces of the die and through which the light beam passes; and at least two ribs located on surfaces of the main body other than the optically functional surfaces and extending in parallel in the main scanning direction. A recessed portion is present on a surface of at least one of the ribs, and the recessed portion has a side transfer surface and a bottom surface, which is a non-transfer surface, and the distance between the optically functional surfaces is less than the length of the main body in the sub-scanning direction.

Abstract: An optical scanning device for guiding a light beam to a member to scan the member with the light beam, including a light source emitting the light beam; a light deflector deflecting the light beam; a focusing optical system including a plastic optical element molded using a die. The optical element has least two transfer surfaces formed by contacting with transfer surfaces of the die and including a light entrance surface and a light exit surface; and a third surface including a non-transfer surface formed without contacting a transfer surface of the die. The light beam passes through the optical element in such a manner that the optical axis center of the light beam extends in a direction parallel to the shorter side of the optical element while being shifted from the dimensional center of the optical element toward the third surface of the optical element.