Nippon Telegraph and Telephone Corporation

Other

Denso Corporation

Hisanobu Dobashi

Shinji Nishimura

Toru Miura

Kiyoshi Takahashi

Masahiro Takiguchi

Tatsuya Hirata

Toshinori Sonehara

Hiromi Sato

Shigeru Date

Tomoaki Ishifuji

Manabu Yamamoto

Tadashi Sato

Kimiaki Ando

Takaya Tanabe

Kikuji Katoh

Ryouzo Yoshino

An IC card whose state of usage can be judged by a user from an appearance of the card, and a relevant IC card system and method are provided. In an IC card fed electricity from an IC card reader-writer via feeding means using one of electromagnetic coupling and electrostatic coupling, and the IC card having an IC chip which communicates with the IC card reader-writer, the possible/impossible state of usage of the card by a user is determined using electric means for disconnecting or non-disconnecting the feeding means or providing another circuit and disconnecting this circuit, and appearance of the IC card is also changed at the time of the change caused by such electric means and thereby the state of usage of the card is indicated to the user.

IC card indicating state of usage and system therefor

A reader/writer (RW) requires identification of anti-collision techniques used by IC cards (A, B, C, and D). The IC cards implement answers to the anti-collision technique identification requirement by the reader/writer at different timings respectively for respective IC cards among the IC cards which use different anti-collision techniques respectively. The reader/writer requires identifications of types of the IC cards in dependence upon the anti-collision techniques in response to the answers by the IC cards. The IC cards return identification data thereof in response to the card type identification requirements by the reader/writer for respective IC cards among the IC cards which use different anti-collision techniques respectively. The reader/writer identifies the types of the IC cards in response to the identification data of the respective IC cards.

Contactless IC card communication system and related method

A reader/writer (RW) requires identification information pieces of respective plural IC cards (A, B, C). The plural IC cards return the respective identification information pieces in response to the requirement by the reader/writer. Logical addresses are assigned to some IC cards among the plural IC cards respectively to cause the reader/writer to select them in response to the return of the identification information pieces by the plural IC cards. The IC cards selected by the reader/writer are controlled. The reader/writer cancels the assignment of the logical address to one of the selected IC cards. The logical address, the assignment of which has been canceled by the reader/writer, is assigned to an IC card among the plural IC cards to which any logical address has not been assigned yet. The IC card to which the logical address has just been assigned is controlled.

Method and system for controlling contactless IC cards

The present invention provides a data readout apparatus and method using optical beams by which high data-recording density for optical recording media and high transfer rate for regenerated data can be realized. The data readout method of the present invention comprises the steps of: making a first optical beam incident on an optical recording medium in a manner such that in three successive tracks n-1, n, and n+1, n being an integer of two or more, on the recording medium, the center of the beam spot of the first optical beam lies, in a transverse direction of the tracks, between the boundary point of tracks n-1 and n and the center of track n-1; making a second optical beam incident on the optical recording medium in a manner such that the center of the beam spot of the second optical beam lies, in the transverse direction of the tracks, between the boundary point of tracks n+1 and n and the center of track n+1; detecting reflected beams of the first and second optical beams from the optical recording medium; and regenerating data recorded on the three tracks in accordance with levels of the detected reflected beams. According to this, data sequences recorded on three successive tracks can be regenerated simultaneously by using two optical beams; thus, even if the track pitch is narrowed, it is possible to detect signals without the influence of crosstalk, and the data transfer rate can be increased. The apparatus for implementing this method allows simpler circuit arrangement.

Optical data readout with two beams on three tracks

Growing community of inventors

Tokyo, Japan

Hisanobu Dobashi