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US5404240A Expired / Lapsed US ⏱️ 0.0 years remaining

Optical switching system for optical wavelength-division and time-division multiplexed signals

Assignee: NEC Corp
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Filing: 1992-02-14
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Granted: 1995-04-04
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Expires: 2012-02-14
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Abstract

Abstract An optical switching system for optical wavelength-division and time-division multiplexed signals includes a plurality of tunable wavelength filters each of which selects a signal having a desired wavelength from an optical wavelength-division and time-division multiplexed signal, a plurality of optical memory elements each of which is supplied with an output signal of each of the plurality of tunable wavelength filters. Each optical memory element memorizes a light intensity of the output signal by being applied with a first control voltage and supplies an output port with the output signal which is converted to have a predetermined wavelength in a desired time slot. The tunable wavelength filters and optical memory elements may by replaced by wavelength filters and tunable wavelength optical memories.

Inventors

  • 👤 Makoto Nishio
  • 👤 Takahiro Numai

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 02:45
CPC Classifications
H; H04; H04Q; H04Q11/00; H04Q11/0001; H04Q11/0005; H04Q2011/0007; H04Q2011/002

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 223 words
An optical switching system for optical wavelength-division and time-division multiplexed signals, comprising: a plurality (n) of tunable wavelength filters each of which selects a signal having a desired wavelength from an optical wavelength-division and time-division multiplexed signal in every time-slot; and a plurality (n) of optical memory elements each of which is connected to a control electrode and supplied with an output signal of a corresponding one of said plurality (n) of tunable wavelength filters, each of said plurality (n) of optical memory elements capable of memorizing a light intensity and "high" or "low" state of said output signal by being applied with a first control voltage received from the control electrode and having a predetermined time width, and supplying an output port with said output signal which is converted to have a predetermined wavelength in a desired time slot, and each of said plurality (n) of optical memory elements further capable of reading out the memorized "high" or "low" state by being applied with a second control voltage having a time width approximately equal to the predetermined time width, the second control voltage being higher than the first control voltage, and the reading-out of the "high" or "low" state being in the form of the presence or non-presence of an output light having a time width supplied from the optical memory element.
Claim 2
Dependent Claim 223 words
An optical switching system for optical wavelength-division and time-division multiplexed signals, comprising: a plurality (n) of tunable wavelength filters each of which selects a signal having a desired wavelength from an optical wavelength-division and time-division multiplexed signal in every time-slot; and a plurality (n) of optical memory elements each of which is connected to a control electrode and supplied with an output signal of a corresponding one of said plurality (n) of tunable wavelength filters, each of said plurality (n) of optical memory elements capable of memorizing a light intensity and "high" or "low" state of said output signal by being applied with a first control voltage received from the control electrode and having a predetermined time width, and supplying an output port with said output signal which is converted to have a predetermined wavelength in a desired time slot, and each of said plurality (n) of optical memory elements further capable of reading out the memorized "high" or "low" state by being applied with a second control voltage having a time width approximately equal to the predetermined time width, the second control voltage being higher than the first control voltage, and the reading-out of the "high" or "low" state being in the form of the presence or non-presence of an output light having a time width supplied from the optical memory element.
Claim 3
Dependent Claim 224 words
An optical switching system for optical wavelength-division and time-division multiplexed signals, comprising: a plurality (n) of wavelength filters each of which selects a signal having a predetermined wavelength from an optical wavelength-division and time-division multiplexed signal; and a plurality (n) of tunable wavelength optical memory elements each of which is connected to a control electrode and supplied with an output signal of a corresponding one of said plurality (n) of wavelength filters, each of said plurality (n) of tunable wavelength optical memory elements capable of memorizing a light intensity and "high" or "low" state of said output signal by being applied with a first control voltage received from the control electrode and having a predetermined time width, and supplying an output port with said output signal which is converted to have a desired wavelength in a desired time slot, and each of said plurality (n) of tunable wavelength optical memory elements further capable of reading out the memorized "high" or "low" state by being applied with a second control voltage having a time width approximately equal to the predetermined time width, the second control voltage being higher than the first control voltage, and the reading-out of the "high" or "low" state being in the form of the presence or non-presence of an output light having a time width supplied from the optical memory element.
Claim 4
Dependent Claim 224 words
An optical switching system for optical wavelength-division and time-division multiplexed signals, comprising: a plurality (n) of wavelength filters each of which selects a signal having a predetermined wavelength from an optical wavelength-division and time-division multiplexed signal; and a plurality (n) of tunable wavelength optical memory elements each of which is connected to a control electrode and supplied with an output signal of a corresponding one of said plurality (n) of wavelength filters, each of said plurality (n) of tunable wavelength optical memory elements capable of memorizing a light intensity and "high" or "low" state of said output signal by being applied with a first control voltage received from the control electrode and having a predetermined time width, and supplying an output port with said output signal which is converted to have a desired wavelength in a desired time slot, and each of said plurality (n) of tunable wavelength optical memory elements further capable of reading out the memorized "high" or "low" state by being applied with a second control voltage having a time width approximately equal to the predetermined time width, the second control voltage being higher than the first control voltage, and the reading-out of the "high" or "low" state being in the form of the presence or non-presence of an output light having a time width supplied from the optical memory element.
Claim 5
Dependent Claim 242 words
An optical switching system for optical wavelength-division and time-division multiplexed signals, comprising: a plurality (k×l×m) of optical switches each of which selectively supplies an output signal at a desired time slot from an optical wavelength-division and time-division multiplexed signal; a plurality (k×l×m) of tunable wavelength filters each of which selects a signal having a desired wavelength from said optical wavelength-division and time-division multiplexed signal in every time-slot; and a plurality (k×l×m) of optical memory elements each of which is connected to a control electrode and keeps supplying an output signal for a corresponding one of said plurality (k×l×m) of tunable wavelength filters for a desired period, said output signal being converted to have a predetermined wavelength, each of said plurality (k×l×m) of optical memory elements capable of memorizing a light intensity and "high" or "low" state of said output signal by being applied with a first control voltage received from the control electrode and having a predetermined time width, and each of said plurality (k×l×m) of optical memory elements further capable of reading out the memorized "high" or "low" state by being applied with a second control voltage having a time width approximately equal to the predetermined time width, the second control voltage being higher than the first control voltage, and the reading-out of the "high" or "low" state being in the form of the presence or non-presence of an output light having a time width supplied from the optical memory element.
Claim 6
Dependent Claim 242 words
An optical switching system for optical wavelength-division and time-division multiplexed signals, comprising: a plurality (k×l×m) of optical switches each of which selectively supplies an output signal at a desired time slot from an optical wavelength-division and time-division multiplexed signal; a plurality (k×l×m) of tunable wavelength filters each of which selects a signal having a desired wavelength from said optical wavelength-division and time-division multiplexed signal in every time-slot; and a plurality (k×l×m) of optical memory elements each of which is connected to a control electrode and keeps supplying an output signal for a corresponding one of said plurality (k×l×m) of tunable wavelength filters for a desired period, said output signal being converted to have a predetermined wavelength, each of said plurality (k×l×m) of optical memory elements capable of memorizing a light intensity and "high" or "low" state of said output signal by being applied with a first control voltage received from the control electrode and having a predetermined time width, and each of said plurality (k×l×m) of optical memory elements further capable of reading out the memorized "high" or "low" state by being applied with a second control voltage having a time width approximately equal to the predetermined time width, the second control voltage being higher than the first control voltage, and the reading-out of the "high" or "low" state being in the form of the presence or non-presence of an output light having a time width supplied from the optical memory element.

References Cited (Backward Citations)

US5111323A Cited
JPS6330092A Cited
JPS6350194A Cited
US5005166A Cited
US5121381A Cited
US5194977A Cited
US5189542A Cited

USPTO Annuity & Maintenance Windows

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