Hitachi Maxell, Limited

Hitachi Maxwell, Ltd.

Hiroyuki Hirata

Osamu Ishizaki

Tsuyoshi Maro

Tatsuo Araki

Hideo Daimon

Masatoshi Hashimoto

Makoto Aihara

Yasuhiko Kokufuda

Masahiro Suzuki

Susumu Shibasaki

Haruo Arai

Hiroyuki Ohta

To implement the alignment of lenses with a simple configuration or by a simple method. A lens unit includes a plurality of lenses each including a lens portion and a flange portion surrounding the lens portion, and a tube portion that holds the plurality of lenses successively arranged along an optical axis. The holder body includes first and second receive portions successively formed along the optical axis. The first receive portion holds the lenses by pressing the side of the flange portion that extends along the optical axis. The second receive portion receives the lens such that the lens can be moved in a direction crossing the optical axis.

Lens unit, camera module and manufacturing method of lens unit

A light shield sheet has an aperture that restricts a range of light transmission. In the light shield sheet, the thickness of the inner circumference in the periphery of the aperture is smaller than the thickness of the outer circumference.

Light shield sheet, optical apparatus, and method of manufacturing light shield sheet

In a lens device, plastic lenses having circular outer periphery are placed in a plastic lens-barrel having an octagonal or more complex polygonal inner surface in such a way that the outer peripheral surfaces of the lenses are press contacted to the inner surface of the polygonal shape. This lens device has press contact portions that are pressed by the lens outer peripheral surface and the lens-barrel inner surface in the vicinity and in both sides of gate traces where optical axis displacement is large so as to suppress the displacement of the gate trace by the press contact portions.

Lens device

A cavity surface-forming plate of a mold for injection-molding a plastic substrate is coarsely polished, and then a surface for defining a cavity is applied with electroless Ni&mdash;P plating. The surface of the plating is polished with abrasive grains to obtain surface roughness of Ra&lE;2.0 nm and Rmax&lE;22 nm. The plastic substrate molded with the mold has smoothness equivalent to the polished plating surface. A concave-convex pattern for forming pits may be formed on the cavity surface. A magnetic disk or an optical disk provided with the substrate makes it possible to realize the near contact system for a magnetic or magneto-optical head. Thus, it is possible to realize high density recording.

Substrate for information recording disk, mold and stamper for injection molding substrate, and method for making stamper, and information recording disk

A recording disk comprises a substrate including a plastic material, and an overlay arranged over the substrate and including a recording substance for recording therein an information, and a radially-outer periphery of the overlay is received within a radially-outer periphery of the substrate as seen in an axial direction of the recording disk.

Recording disk and producing method therefor

A cavity surface-forming plate of a mold for injection-molding a plastic substrate is coarsely polished, and then a surface for defining a cavity is applied with electroless Ni-P plating. The surface of the plating is polished with abrasive grains to obtain surface roughness of Ra.ltoreq.2.0 nm and Rmax.ltoreq.22 nm. The plastic substrate molded with the mold has smoothness equivalent to the polished plating surface. A concave-convex pattern for forming pits may be formed on the cavity surface. A magnetic disk or an optical disk provided with the substrate makes it possible to realize the near contact system for a magnetic or magneto-optical head. Thus, it is possible to realize high density recording.

Growing community of inventors

Ibaraki, Japan

Hiroyuki Hirata