US3766393A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical data transmission system employing polarization-shift, multiple-cavity laser
Assignee: RCA Corp
•
Filing: 1971-11-22
•
Granted: 1973-10-16
•
Expires: 1991-11-22
Abstract
Abstract An internally-modulated laser in which first, second and third reflectors and a polarization means are oriented with respect to each other both to provide a first optical resonant cavity, defined by the first and second reflectors, and a second optical resonant cavity, defined by the first and third reflectors. A laser medium is located in the common portion of the cavities between the first reflector and the polarization means, and an individual data-signal-responsive modulator is situated in each respective individual portion of the cavities between the polarization means and the respective second or third reflector. The first cavity supports a given polarization and the second cavity supports a polarization orthogonal to the given polarization. The modulated output wave energy provided by this apparatus includes two separate orthogonally polarized data channels.
Inventors
- 👤 D Herzog
- 👤 C Reno
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 23:03
CPC Classifications
H; H01; H01S; H01S3/00; H01S3/10; H01S3/106; H01S3/107; H01S3/1075; H01S3/05; H01S3/08; H01S3/081; H01S3/082; H01S3/11; H01S3/1103; H01S3/1106; H01S3/1109
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
300 words
In an optical data transmission system of the type comprising three reflectors for reflecting light of certain wavelengths, an active lasing medium effective when pumped and when located in an optical resonant cavity for generating light of at least one of said certain wavelengths, and polarization means; wherein said active lasing medium is located between a first of said reflectors and said polarization means, a second of said reflectors is located with respect to said polarization means and said first reflector to form a first optical resonant cavity for a first component of said light having a first polarization which passes from said first reflector through said lasing medium and polarization means toward said second reflector, a third of said reflectors is located with respect to said polarization means and said first reflector to form a second optical resonant cavity for a second component of said light having a second polarization in quadrature with said first polarization which passes from said first reflector through said lasing medium and polarization means toward said third reflector; the improvement therein, comprising: modulation means including a signal-controlled polarization shifter located in said first cavity between said polarization means and said second reflector for rotating the polarization of said light which passes therethrough by an amount determined in accordance with the level of a control signal applied to said polarization shifter, wherein said polarization means is oriented with respect to said polarization shifter to eject as an output from said cavities that component of said light having said second polarization which has passed from said second reflector through said polarization shifter to said polarization means, and wherein the length of each of said first and second cavities is substantially equal to an integral number of half-wavelengths of the same given one of said certain wavelengths.
Claim 2
Dependent Claim
300 words
In an optical data transmission system of the type comprising three reflectors for reflecting light of certain wavelengths, an active lasing medium effective when pumped and when located in an optical resonant cavity for generating light of at least one of said certain wavelengths, and polarization means; wherein said active lasing medium is located between a first of said reflectors and said polarization means, a second of said reflectors is located with respect to said polarization means and said first reflector to form a first optical resonant cavity for a first component of said light having a first polarization which passes from said first reflector through said lasing medium and polarization means toward said second reflector, a third of said reflectors is located with respect to said polarization means and said first reflector to form a second optical resonant cavity for a second component of said light having a second polarization in quadrature with said first polarization which passes from said first reflector through said lasing medium and polarization means toward said third reflector; the improvement therein, comprising: modulation means including a signal-controlled polarization shifter located in said first cavity between said polarization means and said second reflector for rotating the polarization of said light which passes therethrough by an amount determined in accordance with the level of a control signal applied to said polarization shifter, wherein said polarization means is oriented with respect to said polarization shifter to eject as an output from said cavities that component of said light having said second polarization which has passed from said second reflector through said polarization shifter to said polarization means, and wherein the length of each of said first and second cavities is substantially equal to an integral number of half-wavelengths of the same given one of said certain wavelengths.
Claim 3
Dependent Claim
45 words
The output data transmission system defined in claim 1, further including an analog signal source coupled to said polarization shifter to provide said control signal thereto for rotating the polarization of said light passing therethrough in accordance with the instantaneous level of said analog signal.
Claim 4
Dependent Claim
132 words
The Optical data transmission system defined in claim 2, further including a second analog signal source, a second signal-controlled polarization shifter having said second signal source coupled thereto to provide said control signal thereto, said second polarization shifter being located in said second cavity between said polarization means and said third reflector for rotating the polarization of said light which passes therethrough by an amount determined in accordance with the instantaneous level of the analog signal applied thereto from said second analog signal source, and wherein said polarization means is oriented with respect to said second polarization shifter to eject as a second output from said cavities that component of said light having said first polarization which has passed from said third reflector through said second polarization shifter to said polarization means.
Claim 5
Dependent Claim
96 words
The optical data transmission system defined in claim 1, wherein said modulation means further includes mode-locking means, and wherein system further includes a periodic signal generator coupled to provide an input to said mode-locking means, said generator generating a frequency substantially equal to an integral multiple of the speed of light divided by twice the length of said first cavity to thereby effect mode-locking with said generated frequency, and a data bit stream source synchronized with said generated frequency, said data bit stream source being coupled to said polarization shifter to provide said control signal thereto.
Claim 6
Dependent Claim
170 words
The optical data transmission system defined in claim 4, wherein said first and second cavities have substantially the same length, and wherein said system further includes a second data bit stream source synchronized with said generated frequency, second modulation means comprising a second signal-controlled polarization shifter having said second data bit stream source coupled thereto to provide said control signal thereto and a second mode-locking means having said generated frequency applied thereto, said second modulation means being located in said second cavity between said polarization means and said third reflector for rotating the polarization of said light which passes through said second polarization shifter by an amount determined by said data bit stream applied thereto from said second data bit stream source, and wherein said polarization means is oriented with respect to said second polarization shifter to eject as a second output from said cavities that component of said light having said first polarization which has passed from said third reflector through said second polarization shifter to said polarization means.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-10-15 | 1977-04-16 | 1977-10-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-15 | 1981-04-16 | 1981-10-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-15 | 1985-04-16 | 1985-10-16 | $7700.00 | Window Closed / Lapsed |