Panasonic Corporation

Panasonic Intellectual Property Management Co., Ltd.

Toshiaki Takasu

Takeharu Yamamoto

Toshiyasu Tanaka

Yasuo Ueda

Noriaki Terahara

Yoshiyuki Hashimoto

Hiroaki Suzuki

Yoshihisa Takahashi

Takahiro Yamada

Kenichi Tanaka

Suguru Nakao

Hiroto Inoue

Makoto Iyoda

Yukihiro Iwata

Yasuo Yokota

Kouretsu Boku

Takeshi Ohta

Akinori Yuba

Satoshi Obase

Seiji Hoshi

Hirotaka Endou

An information recording apparatus includes: a first memory which stores synchronization data for updating data on a recordable optical disc and/or adding data to the recordable optical disc; a second memory which stores erasure information indicating data to be erased; and a controller which controls addition, update, and erasure of data on the optical disc. The controller records the synchronization data onto the optical disc. After recording the synchronization data, the controller records, onto the optical disc, management information indicating the state of the optical disc on which the synchronization data has been recorded and the state of the optical disc resulting from erasure according to the erasure information. Subsequently, the controller closes the session. After closing the session, the controller physically erases the data to be erased which has been recorded on the optical disc.

Apparatus and method for recording and erasing user data on a recordable optical disc

An information recording device including a controller records information in a write-once optical disk group including one or a plurality of write-once optical disks. When recording new data, the controller calculates a residual quantity of an alternate area. The calculation of the residual quantity of the alternate area corresponds to a subtraction of a first consumption size and a second consumption size from a size of the alternate area of the write-once optical disk group. The first consumption size is a size of the alternate area already consumed when the data recorded in the write-once optical disk group was erased. The second consumption size is an estimated size of the alternate area to be consumed when the data recorded in the write-once optical disk group is erased. The controller records the new data when the residual quantity is greater than or equal to a third consumption size.

Information recording device and information recording method

A data erasing method of the present disclosure is a data erasing method for erasing data stripe-recorded in a plurality of write-once optical discs constituting a redundant arrays of inexpensive disks (RAID) system and each including a plurality of data recording blocks and a redundant data block. In the data erasing method, alternate recording of at least one target block and the redundant data block is performed in a predetermined alternate area. The target block is one of the data recording blocks in which target data as erase target data is recorded. The target block is overwritten such that the target data is not correctly read.

Data erasing method

In an electronic device including a temperature sensor and an electronic component which is a heat generation source, the temperature is measured while the influence of heat from the electronic component is reduced. The electronic device includes: a base formed of a resin material; a board which is disposed at one side of the base, and includes an electronic component and a temperature sensor; and a heat sink which is disposed at the other side of the base for dissipating heat generated by the electronic component. The heat sink includes an extension part extending from the other side of the base toward a position of the board at which the electronic component is provided.

Electronic device

In an optical pickup device, a supporting basethat has a main-shaft bearingwith two concentric round holes to pass a main shaftthrough is formed out of a synthetic resin. On the other hand, an optical base, which has a sub-shaft bearingto pass a sub-shaftthrough and which supports a light emitter, a beam splitter, a collimator lensand a photodetector, is formed by metal die casting process. And a pickup frameis formed by bonding the supporting baseand the optical basetogether with an adhesive.

Pickup frame and optical pickup device

An optical pickup device has a DVD/CD laser diode for emitting a DVD/CD laser beam as linear polarized light, and a BD laser diode for emitting a BD laser beam. The optical pickup device has a dichroic mirror that regularly reflects a part of the DVD/CD laser beam, transmits a part of the DVD/CD laser beam, and transmits return light of the BD laser beam. The dichroic mirror is formed so that a product of reflectance of outward light of the DVD/CD laser beam and transmittance of return light of the DVD/CD laser beam becomes 20% or more to 25% or less. A light receiving element receives the return light of the DVD/CD laser beam transmitted through the dichroic mirror or the return light of the BD laser beam transmitted through the dichroic mirror.

Optical pickup device

By providing a coloring agent, which is brought in contact with the liquid fuel leaked from an outer peripheral portion of the liquid fuel holding section that is configured to hold the liquid fuel and by which the contact portion is changed in color, in at least part of the outer peripheral portion, the leakage of the liquid fuel from the liquid fuel holding section can be visually detected swiftly and easily without providing any special detection device.

Liquid fuel container, fuel cell system, and portable information terminal device

Growing community of inventors

Osaka, Japan

Toshiaki Takasu