Patent EP0345696A2 successfully refreshed from Google Patents.
EP0345696A2
Expired / Lapsed
EP
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Data reproducing system
Assignee: Mitsubishi Electric Corp
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Filing: 1989-06-05
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Granted: —
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Expires: 2009-06-05
Abstract
Abstract When current is caused to pass between a data carrier (20) and a stylus (23) while causing the latter to approach the former, a tunnel current is produced when the distance between the two is reduced to a certain extent. According to the invention, the data carrier and stylus are made of a conductive material, and a closed circuit for passing current therethrough is formed between the data carrier and stylus. Raised or recessed portions (22) formed on the surface of the data carrier can be read out to reproduce data by detecting the tunnel current flowing through the closed circuit.
Inventors
- 👤 Michihiro C/O Mitsubishi Denki Tadokoro
- 👤 Kazuo C/O Mitsubishi Denki Okada
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 17:04
CPC Classifications
G; G11; G11B; G11B11/00; G11B11/08; G11B11/03; G11B21/00; G11B21/16; G11B21/20; G11B21/21
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
94 words
A data reproducing system comprising an electrically conductive data carrier with data recorded thereon in terms of difference in level, an electrically conductive stylus disposed such that a tunnel current flows between said stylus and data carrier, drive means for controlling the distance between said stylus and data carrier according to a control signal, a first operational circuit for providing said control signal to said drive means such as to hold said tunnel current constant and a second operational circuit for taking out data recorded on said data carrier by processing said control signal.
Claim 2
Dependent Claim
94 words
A data reproducing system comprising an electrically conductive data carrier with data recorded thereon in terms of difference in level, an electrically conductive stylus disposed such that a tunnel current flows between said stylus and data carrier, drive means for controlling the distance between said stylus and data carrier according to a control signal, a first operational circuit for providing said control signal to said drive means such as to hold said tunnel current constant and a second operational circuit for taking out data recorded on said data carrier by processing said control signal.
Claim 3
Dependent Claim
110 words
A data reproducing system comprising an electrically conductive data carrier with data recorded thereon in terms of difference in level, an electrically conductive stylus disposed such that a tunnel current flows through said stylus and data carrier, drive means for controlling the distance between said stylus and data carrier according to a control signal, a low-pass filter for passing a low frequency component of said tunnel current, a first operational circuit for providing said control signal to said drive means such as to hold the output of said low-pass filter constant and a second operational circuit for taking out data recorded on said data carrier by processing said tunnel current.
Claim 4
Dependent Claim
110 words
A data reproducing system comprising an electrically conductive data carrier with data recorded thereon in terms of difference in level, an electrically conductive stylus disposed such that a tunnel current flows through said stylus and data carrier, drive means for controlling the distance between said stylus and data carrier according to a control signal, a low-pass filter for passing a low frequency component of said tunnel current, a first operational circuit for providing said control signal to said drive means such as to hold the output of said low-pass filter constant and a second operational circuit for taking out data recorded on said data carrier by processing said tunnel current.
Claim 5
Dependent Claim
19 words
The data reproducing system according to claim 1 or 2, wherein said drive means consists of a piezoelectric element.
Claim 6
Dependent Claim
27 words
The data reproducing system according to claim 1 or 2, wherein said data carrier consists of a disk having a surface formed with raised or recessed portions.
Claim 7
Dependent Claim
22 words
The data reproducing system according to claim 1 or 2, wherein said first and second operational circuits consist of respective operational amplifiers.
Claim 8
Dependent Claim
45 words
The data reproducing system according to claim 1 or 2, wherein said data carrier is electrically connected to a shaft of a motor for rotating said data carrier, and said tunnel current flowing between said stylus and data carrier is taken out from said shaft.
References Cited (Backward Citations)
No citation records indexed.
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