Patents by Inventor David M. Pepper

David M. Pepper has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 11953776
    Abstract: A diffraction-limited, programmable pulse shaping network using a virtually integrated phased array (VIPA)-grating pair, integrated with a 2-d transmissive phase-only spatial light modulator (SLM) and a retro-array phase-conjugate mirror (RA-PCM). A high-temporal resolution, broadband pulse shaping network is realized using a 2-D VIPA-grating dispersive element pair, with a programmable SLM at a common Fourier transform plane. True wavefront reversal (“time reversal”) is realized using a self-starting RA-PCM, which compensates for system path distortions, misalignment, beam wander, vibrations and optical aberrations. Upon reverse transit through the system, the RA-PCM wavefront matches the set of virtual images emerging from the VIPA. The RA-PCM is a self-starting, low-power device, without frequency shifts, doesn't require pump beams and/or the need for high-intensity stimulated scattering threshold conditions to be met.
    Type: Grant
    Filed: January 26, 2022
    Date of Patent: April 9, 2024
    Inventor: David M. Pepper
  • Publication number: 20230236455
    Abstract: A diffraction-limited, programmable pulse shaping network using a virtually integrated phased array (VIPA)-grating pair, integrated with a 2-d transmissive phase-only spatial light modulator (SLM) and a retro-array phase-conjugate mirror (RA-PCM). A high-temporal resolution, broadband pulse shaping network is realized using a 2-D VIPA-grating dispersive element pair, with a programmable SLM at a common Fourier transform plane. True wavefront reversal (“time reversal”) is realized using a self-starting RA-PCM, which compensates for system path distortions, misalignment, beam wander, vibrations and optical aberrations. Upon reverse transit through the system, the RA-PCM wavefront matches the set of virtual images emerging from the VIPA. The RA-PCM is a self-starting, low-power device, without frequency shifts, doesn't require pump beams and/or the need for high-intensity stimulated scattering threshold conditions to be met.
    Type: Application
    Filed: January 26, 2022
    Publication date: July 27, 2023
    Inventor: David M. Pepper
  • Publication number: 20230216266
    Abstract: A spatially and spectrally distributed long-laser system. Spatially separated phase-conjugate mirrors (PCMs) define a long-laser resonator cavity. The PCMs define, respectively, a power transmitting unit (master), and a power receiving unit (slave), as well as providing a secure two-way communications link between the units. The long-laser is mode-locked, minimizing third-party interception and detection. A wavefront-reversal device, using a MEMS spatial phase modulator, integrated with a retroreflector array, provides a true phase-conjugate (time-reversed) replica of the beam at each end of the system, providing auto-alignment, diffraction-limited performance, compensation for static and dynamic phase and polarization distortions, minimizing the FOV and scattering. The retroreflecting array initiates the oscillation mode. The SPM adaptive optical system bootstraps the retro-array by forming a simultaneous closed-loop system.
    Type: Application
    Filed: December 30, 2021
    Publication date: July 6, 2023
    Inventor: David M. Pepper
  • Patent number: 8681421
    Abstract: An IR laser source providing light in the IR spectrum, the laser source comprising a pump laser operating at a frequency equivalent to wavelength shorter than 2 ?m and at a predetermined power, and an optic fiber coupled to the pump laser. The optic fiber has at least a section of a hollow core photonic crystal fiber, the at least a section of hollow core photonic crystal fiber being designed to have at least a passband in the IR spectrum and being filled with a molecular gas for triggering at least one Stoke's shift in the light entering the at least a section of hollow core photonic crystal fiber for the particular power of the pump laser, the at least one Stoke's shift be selected to cause the light entering the at least a section of hollow core photonic crystal fiber to shift in frequency into the passband in the IR spectrum of the hollow core photonic crystal fiber.
    Type: Grant
    Filed: September 17, 2010
    Date of Patent: March 25, 2014
    Assignee: HRL Laboratories, LLC
    Inventors: David M. Pepper, Hans Bruesselbach, Bryan Fong
  • Patent number: 8228582
    Abstract: An optical MEMS retro-reflective apparatus with modulation capability having a retro-reflecting structure including a pair of reflective surfaces; and a MEMS device for moving at least one of the reflective surfaces of said pair of reflective surfaces relative to another one of the reflective surfaces of said pair of reflective surfaces a distance which causes the pair of reflective surfaces to switch between a reflective mode of operation and a transmissive mode of operation. A substrate and a moveable grating structure may be substituted for the reflective surfaces.
    Type: Grant
    Filed: April 9, 2010
    Date of Patent: July 24, 2012
    Assignee: HRL Laboratories, LLC
    Inventors: David M. Pepper, Keyvan Sayyah
  • Patent number: 8229304
    Abstract: A coherent laser receiver for receiving encoded light which may have propagated over an aberrated path, situated between a source of the encoded light and the coherent receiver. The coherent laser receiver comprises a bundle of optical fibers arranged in an array to receive light, as encoded from a distant optical transmitter or reflective surface, the encoded light from the distant optical transmitter or reflective surface is received by at least a majority of the fibers in the array. A plurality of light amplifiers is provided for amplifying the received encoded light.
    Type: Grant
    Filed: April 30, 2009
    Date of Patent: July 24, 2012
    Assignee: HRL Laboratories, LLC
    Inventors: David M. Pepper, Monica Minden
  • Patent number: 8030122
    Abstract: A method and apparatus for a photoinduced electromotive force sensor. The sensor has an active substrate formed of a semi-insulating photoconductor with sufficient carrier trap density to form an effective charge grating and pairs of electrodes disposed on the active substrate, where the sensor is configured to reduce the photovoltaic effect caused by the incident light in the vicinity of the electrodes. The shape or composition of the electrodes may be selected to reduce the photovoltaic effect or the electrodes may be disposed on the substrate to average out the photovoltaic effect arising from each one of the electrodes.
    Type: Grant
    Filed: February 25, 2010
    Date of Patent: October 4, 2011
    Assignee: HRL Laboratories, LLC
    Inventors: David M. Pepper, Gilmore J. Dunning, Marvin B. Klein, Gerald David Bacher, Bruno Pouet
  • Patent number: 7821704
    Abstract: An IR laser source providing light in the IR spectrum, the laser source comprising a pump laser operating at a frequency equivalent to wavelength shorter than 2 ?m and at a predetermined power, and an optic fiber coupled to the pump laser. The optic fiber has at least a section of a hollow core photonic crystal fiber, the at least a section of hollow core photonic crystal fiber being designed to have at least a passband in the IR spectrum and being filled with a molecular gas for triggering at least one Stoke's shift in the light entering the at least a section of hollow core photonic crystal fiber for the particular power of the pump laser, the at least one Stoke's shift be selected to cause the light entering the at least a section of hollow core photonic crystal fiber to shift in frequency into the passband in the IR spectrum of the hollow core photonic crystal fiber.
    Type: Grant
    Filed: May 21, 2007
    Date of Patent: October 26, 2010
    Assignee: HRL Laboratories, LLC
    Inventors: David M. Pepper, Hans Bruesselbach, Bryan Fong
  • Patent number: 7729572
    Abstract: An optical time delay module has a plurality of time delay elements connected in a series and a plurality an optical output couplers wherein each of said optical output couplers is operationally connected between one or more time delay elements in said series, the optical output couplers providing a plurality of optical outputs from said module with different optical delays controlled by an analog voltage.
    Type: Grant
    Filed: July 8, 2008
    Date of Patent: June 1, 2010
    Assignee: HRL Laboratories, LLC
    Inventors: David M. Pepper, David Sumida, Richard P. Berg
  • Patent number: 7729030
    Abstract: An optical MEMS retro-reflective apparatus with modulation capability having a retro-reflecting structure including a pair of reflective surfaces; and a MEMS device for moving at least one of the reflective surfaces of said pair of reflective surfaces relative to another one of the reflective surfaces of said pair of reflective surfaces a distance which causes the pair of reflective surfaces to switch between a reflective mode of operation and a transmissive mode of operation. A substrate and a moveable grating structure may be substituted for the reflective surfaces.
    Type: Grant
    Filed: September 11, 2003
    Date of Patent: June 1, 2010
    Assignee: HRl Laboratories, LLC
    Inventors: David M. Pepper, Keyvan Sayyah
  • Patent number: 7724994
    Abstract: An optical time delay module has a plurality of time delay elements connected in a series and a plurality an optical output couplers wherein each of said optical output couplers is operationally connected between one or more time delay elements in said series, the optical output couplers providing a plurality of optical outputs from said module with different optical delays controlled by a digital control word.
    Type: Grant
    Filed: February 4, 2008
    Date of Patent: May 25, 2010
    Assignee: HRL Laboratories, LLC
    Inventors: David M. Pepper, David Sumida
  • Patent number: 7701027
    Abstract: A method and apparatus for a photoinduced electromotive force sensor. The sensor has an active substrate formed of a semi-insulating photoconductor with sufficient carrier trap density to form an effective charge grating and pairs of electrodes disposed on the active substrate, where the sensor is configured to reduce the photovoltaic effect caused by the incident light in the vicinity of the electrodes. The shape or composition of the electrodes may be selected to reduce the photovoltaic effect or the electrodes may be disposed on the substrate to average out the photovoltaic effect arising from each one of the electrodes.
    Type: Grant
    Filed: March 3, 2006
    Date of Patent: April 20, 2010
    Assignee: HRL Laboratories, LLC
    Inventors: David M. Pepper, Gilmore J. Dunning, Marvin B. Klein, Gerald David Bacher, Bruno Pouet
  • Patent number: 7486893
    Abstract: The disclosed technology provides a dynamic interconnection system which allows to couple a pair of optical beams carrying modulation information. In accordance with the disclosed technology, two optical beams emanate from transceivers at two different locations. Each beam may not see the other beam point of origin (non-line-of-sight link), but both beams can see a third platform that contains the system of the disclosed technology. Each beam incident on the interconnection system is directed into the reverse direction of the other, so that each transceiver will detect the beam which emanated from the other transceiver. The system dynamically compensates for propagation distortions preferably using closed-loop optical devices, while preserving the information encoded on each beam.
    Type: Grant
    Filed: August 15, 2005
    Date of Patent: February 3, 2009
    Assignee: HRL Laboratories, LLC
    Inventors: David M. Pepper, Richard P. Berg
  • Patent number: 7471454
    Abstract: In some embodiments, a dynamic optical tag communication system is provided which includes high and low index CCR, both having a modulator, such as TCFP-MQWs on a first side of the CCR configured to modulate in a first temperature range, and a modulator on a second side of the CCR to modulate in a second temperature range. In some embodiments another high index CCR having corresponding first and second temperature range modulators is provided. In some embodiments, a CCR may have three modulators, such as MQWs, one configured to modulate in a first temperature range, another to modulate in a second temperature range, and yet another to modulate in a third temperature range. In some embodiments, a dynamic optical tag communication system has CCRs which include a high index CCR having a DDG modulator and a low index CCR having a DDG modulator.
    Type: Grant
    Filed: January 24, 2008
    Date of Patent: December 30, 2008
    Assignee: HRL Laboratories, LLC
    Inventors: Keyvan Sayyah, David M. Pepper
  • Patent number: 7382465
    Abstract: A vibrometer system for determining the vibration spectrum of an object under examination. The vibrometer includes a bundle of optical fibers arranged in an array, wherein a majority of the fibers in the array are arranged to receive light reflected from the object under examination and a minority of the fibers in the array are arranged to transmit light to illuminate the object under examination, wherein the light reflected from the object under test by received by the majority of fibers was transmitted by the minority of fibers; a plurality of light amplifiers and detectors for amplifying and detecting the received light; and a coherent detector responsive to the detected light and to the transmitted light for providing an output signal representative of the vibration spectrum of the object under examination.
    Type: Grant
    Filed: August 25, 2006
    Date of Patent: June 3, 2008
    Assignee: HRL Laboratories, LLC
    Inventor: David M. Pepper
  • Patent number: 7345804
    Abstract: In some embodiments, a dynamic optical tag communication system is provided which includes high and low index CCR, both having a modulator, such as TCFP-MQWs on a first side of the CCR configured to modulate in a first temperature range, and a modulator on a second side of the CCR to modulate in a second temperature range. In some embodiments another high index CCR having corresponding first and second temperature range modulators is provided. In some embodiments, a CCR may have three modulators, such as MQWs, one configured to modulate in a first temperature range, another to modulate in a second temperature range, and yet another to modulate in a third temperature range. In some embodiments, a dynamic optical tag communication system has CCRs which include a high index CCR having a DDG modulator and a low index CCR having a DDG modulator.
    Type: Grant
    Filed: June 19, 2006
    Date of Patent: March 18, 2008
    Assignee: HRL Laboratories, LLC
    Inventors: Keyvan Sayyah, David M. Pepper
  • Patent number: 7330665
    Abstract: An optical frequency modulated transmitter includes a plurality of separately phased-controlled slave lasers, the outputs of which are combined to form a single output beam of the transmitter. A master optical oscillator outputs an optical signal for injection locking the plurality of slave lasers, the optical signal being frequency modulated directly in the master optical oscillator or externally thereof. Additionally, a method of frequency modulating an optical beam is disclosed using a plurality of slave lasers. Each of the slave lasers has an output, the outputs of which are combined to form the optical beam. The plurality of slave lasers is injection locked to an optical output of a master oscillator. The optical output of the master oscillator is frequency modulated before the optical output is applied to the plurality of lasers. Each slave laser of the plurality is phased controlled relative to other slave lasers of the plurality.
    Type: Grant
    Filed: July 29, 2003
    Date of Patent: February 12, 2008
    Assignee: HRL Laboratories, LLC
    Inventors: Daniel Yap, David M. Pepper, Gilmore J. Dunning
  • Patent number: 7292791
    Abstract: In a method and apparatus for converting optical wavelength division multiplexed channels to wireless channels, the information carrying optical carriers are first de-multiplexed and each optical carrier is then extracted from the data using an optical channelizing technique. The optical frequency of each of the extracted optical carriers is then shifted by an amount equal to the desired wireless carrier frequencies in the broadband wireless channels. Optical heterodyning of the frequency-shifted extracted lightwave carriers with the original data-containing optical signals, which are mutually in phase coherence, in a photodetector results in a set of wireless carriers each modulated with the data carried by the corresponding optical channel.
    Type: Grant
    Filed: June 21, 2004
    Date of Patent: November 6, 2007
    Assignee: HRL Laboratories, LLC
    Inventors: Keyvan Sayyah, Hossein Izadpanah, David M. Pepper
  • Patent number: 7283751
    Abstract: A method and apparatus for compensating for phase fluctuations incurred by an optical beam travelling through free space, especially a turbulent atmosphere. A transmitting station transmits a plurality of uniquely tagged optical beams through free space. The plurality of uniquely tagged optical beams are received at a receiving station, where a parameter of each uniquely tagged optical beam is quantified. Information associated with the quantified parameter for each uniquely tagged optical beam is then sent back to the transmitting station via a wireless feedback link. Using the information, the transmitting station adjusts at least one uniquely tagged optical beam to compensate for phase fluctuations.
    Type: Grant
    Filed: January 15, 2004
    Date of Patent: October 16, 2007
    Assignee: HRL Laboratories, LLC
    Inventors: Hans W. Bruesselbach, Monica Minden, Metin S. Mangir, Cris Jones, David M. Pepper
  • Patent number: 7262861
    Abstract: A laser ultrasonic inspection apparatus and method which enables remote sensing of thickness, hardness, temperature and/or internal defect detection is disclosed. A laser generator impinges a workpiece with light for generating a thermo-elastic acoustic reaction in a workpiece. A probe laser impinges the workpiece with an annularly-shaped probe light for interaction with the acoustic signal in the workpiece resulting in a modulated return beam. A photodetector having a sensitive region for detecting an annularly-shaped fringe pattern generated by an interaction of a reference signal and with the modulated return beam at said sensitive region.
    Type: Grant
    Filed: May 24, 2004
    Date of Patent: August 28, 2007
    Assignee: MRL Laboratories, LLC
    Inventors: David M. Pepper, Thomas R. O'Meara