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USH933H Expired / Lapsed US ⏱️ 0.0 years remaining

Infrared coherent optical sensor

Assignee: GOVERNMENT OF UNITED STATES UNITED STATES AIR FORCE, Secretary of
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Filing: 1987-01-14
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Granted: 1991-07-02
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Expires: 2007-01-14
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Abstract

Abstract A dual-beam amplitude-modulated laser transmitter/receiver suitable for laser-radar applications is scalable to high powers because there is no active modulator element that the laser beam passes through. The transceiver comprises a laser source with two separate independent laser optical cavities. Each laser cavity is similar, but each operates at its own frequency. Signals from the two cavities are superimposed at a combining beam splitter to form two transmitter output beams with each combined beam intensity modulated at the laser difference frequency. The output consists of two beams separated in elevation and with equal beam powers from each laser cavity the intensity modulation is 100%. Each beam has its own homodyne detector and separate local oscillator. Thus, each beam path is considered to be a distinct homodyne transceiver. If the frequency of one of the laser sources is changed in time, an AM/FM/CW output suitable for absolute range measurements and fine doppler is generated. The laser transmitter does not require internal or external modulators such as acousto-optic or electro-optic cells. Thus, it is not limited by the modulator characteristics.

Inventors

  • 👤 Carl J. Buczek
  • 👤 Vito F. Pizzurro

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 15:15
CPC Classifications
H; H01; H01S; H01S3/00; H01S3/10; H01S3/13; H01S3/139; G; G01; G01S; G01S17/00; G01S17/02; G01S17/06; G01S17/08; G01S17/32; G01S17/36; G01S17/42; G01S7/00; G01S7/48; G01S7/481; G01S7/4814; G01S7/4815; G01S7/491; G01S7/4911; G01S7/4912; G01S7/4917; H01S3/05; H01S3/06; H01S3/07; H01S3/073; H01S3/076; H01S3/23; H01S3/2383

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 143 words
A dual-beam amplitude-modulated laser transmitter/receiver suitable for laser-radar applications that is scalable to high powers, comprising: a laser source with two separate independent laser optical cavities, each operating at its own frequency, a combining beam splitter at which signals from the two cavities are superimposed to form two transmitter output beams with each combined beam intensity modulated at the laser difference frequency, so that the output consists of two beams separated in elevation and with equal beam powers from each laser cavity with intensity modulation of 100%, Optical means following the combining beam splitter for processing and transmitting the two beams, reflected energy from the two beams being received at the optical means and directed to receiving means, in which each beam has its own homodyne detector and separate local oscillator, whereby means associated with each beam path forms a distinct homodyne transceiver.
Claim 2
Dependent Claim 143 words
A dual-beam amplitude-modulated laser transmitter/receiver suitable for laser-radar applications that is scalable to high powers, comprising: a laser source with two separate independent laser optical cavities, each operating at its own frequency, a combining beam splitter at which signals from the two cavities are superimposed to form two transmitter output beams with each combined beam intensity modulated at the laser difference frequency, so that the output consists of two beams separated in elevation and with equal beam powers from each laser cavity with intensity modulation of 100%, Optical means following the combining beam splitter for processing and transmitting the two beams, reflected energy from the two beams being received at the optical means and directed to receiving means, in which each beam has its own homodyne detector and separate local oscillator, whereby means associated with each beam path forms a distinct homodyne transceiver.
Claim 3
Dependent Claim 40 words
A dual-beam amplitude-modulated laser transmitter/receiver according to claim 1, having means for the frequency of one of the laser sources to be changed in time, so that a modulated output suitable for absolute range measurements and fine doppler is generated.
Claim 4
Dependent Claim 28 words
A dual-beam amplitude-modulated laser transmitter/receiver according to claim 1, having means for laser injection locking in conjunction with means for laser frequency tracking to provide laser tracking stability.
Claim 5
Dependent Claim 28 words
A dual-beam amplitude-modulated laser transmitter/receiver according to claim 1, in which said optical means includes azimuth scanning means, elevation scanning means, azimuth pointer means, and an afocal telescope.
Claim 6
Dependent Claim 27 words
A dual-beam amplitude-modulated laser transmitter/receiver according to claim 4, in which said optical means further includes channel combining prism means including a λ/4 plate for each beam.
Claim 7
Dependent Claim 25 words
A dual-beam amplitude-modulated laser transmitter/receiver according to claim 4, in which said optical means further includes dynamic beam combining means including dynamic galvonometer control means.

References Cited (Backward Citations)

US3258597A Cited
US3302027A Cited
US3409369A Cited
US3573463A Cited
US4195221A Cited
US4391515A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1994-07-01 1994-12-31 1995-07-02 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1998-07-01 1998-12-31 1999-07-02 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2002-07-01 2002-12-31 2003-07-02 $7700.00 Window Closed / Lapsed

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