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US4092640A Expired / Lapsed US ⏱️ 0.0 years remaining

Key input means having a switching element made of a light emitting diode

Assignee: Sharp Corp
•
Filing: 1976-09-27
•
Granted: 1978-05-30
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Expires: 1996-09-27
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Abstract

Abstract A light emitting diode has a metal casing connected to the cathode electrode thereof to protect the light emitting diode from the ambient conditions. Detector circuitry is provided for detecting touch operation by an operator to the metal casing of the light emitting diode. A driver is responsive to the output of the detector circuitry for enabling the light emitting diode when the touch operation is effected to the metal casing of the light emitting diode.

Inventors

  • 👤 Masaharu Satoh

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 21:51
CPC Classifications
H; H03; H03K; H03K17/00; H03K17/94; H03K17/965; H03K17/975; H03K17/98

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 82 words
A key input means comprising: a. a light emitting diode; b. a metal cap formed on or around the light emitting diode and electrically connected with the cathode terminal of the light emitting diode; c. a detection means connected to the cathode terminal of the light emitting diode for developing a detection signal when the operator touches the metal cap; and d. a driving means for activating the light emitting diode in response to the detection signal derived from the detection means.
Claim 2
Dependent Claim 82 words
A key input means comprising: a. a light emitting diode; b. a metal cap formed on or around the light emitting diode and electrically connected with the cathode terminal of the light emitting diode; c. a detection means connected to the cathode terminal of the light emitting diode for developing a detection signal when the operator touches the metal cap; and d. a driving means for activating the light emitting diode in response to the detection signal derived from the detection means.
Claim 3
Dependent Claim 57 words
The key input means of claim 1, wherein the light emitting diode comprises a light emitting diode chip, a resin molded onto the light emitting diode chip, and said metal cap includes a transparent metal film formed on the molded resin, the transparent metal film being electrically connected to the cathode terminal of the light emitting diode.
Claim 4
Dependent Claim 20 words
The key input means of claim 2, wherein the transparent metal film is formed through the use of evaporation techniques.
Claim 5
Dependent Claim 51 words
The key input means of claim 1, wherein the detection means comprises an amplifier for detecting the electric potential of a human operator appearing at the cathode terminal of the light emitting diode, and an AND gate for developing the detection signal in response to the output signal of the amplifier.
Claim 6
Dependent Claim 54 words
The key input means of claim 4, which further comprises a shift register connected to receive the output signal of the AND gate and, wherein the AND gate is connected to receive the output signal of the amplifier and a timing signal for controlling the introduction of the detection signal into the shift register.
Claim 7
Dependent Claim 38 words
The key input means of claim 5, which further comprises an exclusive-OR gate through which the detection signal derived from the AND gate is applied to the shift register and the contents of the shift resister are circulated.
Claim 8
Dependent Claim 29 words
The key input means of claim 1, wherein the driving means comprises a switching transistor interposed between the cathode terminal of the light emitting diode and the grounded terminal.
Claim 9
Dependent Claim 93 words
A keyboard means comprising: a. a plurality of light emitting diodes; b. metal caps formed on or around the each of said light emitting diodes and electrically connected with the respective cathode terminals of the light emitting diodes; c. detection means connected to the respective cathode terminals of the light emitting diodes for developing detection signals when the operator touches the metal caps formed on or around the light emitting diodes; and d. driving means for activating the corresponding light emitting diodes in response to the detection signals derived from the detection means.
Claim 10
Dependent Claim 93 words
A keyboard means comprising: a. a plurality of light emitting diodes; b. metal caps formed on or around the each of said light emitting diodes and electrically connected with the respective cathode terminals of the light emitting diodes; c. detection means connected to the respective cathode terminals of the light emitting diodes for developing detection signals when the operator touches the metal caps formed on or around the light emitting diodes; and d. driving means for activating the corresponding light emitting diodes in response to the detection signals derived from the detection means.
Claim 11
Dependent Claim 19 words
The keyboard means of claim 8, wherein the plurality of light emitting diodes are aligned in a matrix pattern.

References Cited (Backward Citations)

US3581124A Cited
US3683370A Cited
US3737670A Cited
US3879618A Cited
US3732389A Cited
US3772685A Cited
US3971013A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1981-05-29 1981-11-28 1982-05-30 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1985-05-29 1985-11-28 1986-05-30 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1989-05-29 1989-11-28 1990-05-30 $7700.00 Window Closed / Lapsed

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