Lockheed Martin Corporation

Lockheed Martin Coherent Technologies, Inc.

Philip Gatt

Brian C Redman

Samuel Trent Thurman

John Glennon

Piotr Konrad Kondratko

Bruce Gregory Tiemann

Brian Krause

Paul J M Suni

Paul J Suni

Derek Hutton

Peter G Wanninger

Keith Stabler Barr

Carl R Anderson

Mark W Phillips

Christopher Michael Ryan

Systems and methods are provided for a digital holography system. The subject system uses wide-bandwidth data, monitor beams, and signal beams to form a digital interference, yielding a reference phase and angle that can be used to compensate DH phase errors. DH systems disclosed herein can provide an ability to sense and correct for phase errors and/or instabilities to perform DH vibrometry. Such a system provides a compact and low-cost solution to improve sensing in, for example, systems that rely on phase stability for precision 3D and/or vibration imaging.

Phase compensation method for digital holography systems

A heterodyne phase-controlled beam-combiner system includes a laser source, a first beam splitter, a plurality of phase modulators, a tiled array and an optical mixer. The laser source generates a light beam, and the first beam splitter splits the light beam into multiple beamlets. A phase modulator tags each beamlet with an arbitrary phase dither signal corresponding to an arbitrary phase setpoint or offset, and a tiled array, including a number of lenslets, combines the tagged beamlets and directs the combined light to a second beam splitter. The optical mixer generates a heterodyne light including tagging information. A first output light of the second beam splitter is a target light directed to a target, and the arbitrary phase offset enables achieving a nonflat phase profile for beamlets to obtain the desired on-axis far-field intensity of the target light.

Phase-controlled beam combiners

A system for determining airborne light detection and ranging (lidar) installation angles includes an airborne platform, a light detection and ranging (lidar) apparatus, a navigation system and a processor. The airborne platform performs a calibration flight in an orbit. The lidar apparatus is installed on the airborne platform for wind-velocity measurement. The navigation system is on board the airborne platform and measures motion data associated with movements of the airborne platform and generates a navigation signal. The processor determines in real time one or more installation angles of the lidar apparatus on the airborne platform to improve accuracy of the wind-velocity measurement.

Method to determine airborne lidar installation angles using ground returns and INS/GPS data

A LIDAR device includes an array of lasers and an array of corresponding receivers. The spatial distribution of the lasers corresponds to that of the receivers. The array of lasers creates an array of beamlets and correlated receiver fields of view for dense three-dimensional point cloud mapping with precise angular spacing defined by lithographically grown transmitter and receiver arrays. A transmitter lens may be provided that maximizes optical throughput in a coaxial LIDAR by crossing the transmitter beamlets at the focus of the transmitter lens, where a transmit and receive combiner is also located. A single transmitter lens may be used to both collimate and steer the transmitter beamlets to generate a desired spot pattern in angle space. Control circuitry for the lasers may include a drive transistor with a power source coupled to a source terminal and an isolated gate driver coupled to a gate terminal.

Laser-array lidar devices

Systems and methods are provided for a digital holography range Doppler receiver. The subject system transmits outgoing electromagnetic radiation to a target, and provides a first reference local oscillator (LO) beam to a first detector and a second reference LO beam to a second detector, based on the outgoing electromagnetic radiation. The system receives reflected electromagnetic radiation from the target through a first optical receiver and a second optical receiver having a smaller diameter, and determines range and velocity of the target simultaneously using an interference with the second reference LO beam. The system applies time and frequency offsets to the first reference LO beam based on the measured range and velocity to align the first reference LO beam with the reflected electromagnetic radiation, and produces an image of the target using the first reference LO beam having the applied time and frequency offsets.

Digital holography range Doppler receiver

A reconfigurable photonic integrated circuit focal plane array (RPIC-FPA) includes detectors and photonic integrated circuit coupled to the detectors that are configured to mix a return signal beam with local oscillator (LO) beams to produce a combined beam and direct the combined beam to the detectors. The LO beams have reconfigurable optical properties enabled by the RTIC-FPA. The LO beams are individually addressed to switch the detectors between a direct detection mode and various coherent detection modes based on adjustments to the optical properties of the LO beams. In the coherent detection mode, the controller is configured to mix the return signal beam with the LO beam having adjusted optical properties to produce the combined beam, and, in the direct detection mode, the controller is configured to disable the LO beams based on adjustments to the optical properties and to direct the return signal beam to the detectors without mixing.

Reconfigurable photonic integrated circuit focal plane array

A reconfigurable photonic integrated circuit focal plane array (RPIC-FPA) includes detectors and photonic integrated circuit coupled to the detectors that are configured to mix a return signal beam with local oscillator (LO) beams to produce a combined beam and direct the combined beam to the detectors. The LO beams have reconfigurable optical properties enabled by the RPIC-FPA. The LO beams are individually addressed to switch the detectors between a direct detection mode and various coherent detection modes based on adjustments to the optical properties of the LO beams. In the coherent detection mode, the controller is configured to mix the return signal beam with the LO beam having adjusted optical properties to produce the combined beam, and, in the direct detection mode, the controller is configured to disable the LO beams based on adjustments to the optical properties and to direct the return signal beam to the detectors without mixing.

A remote sensor capable of imaging vibrations at many simultaneous points using high-speed imaging cameras is disclosed. The preferred embodiment operates in heterodyne detection mode using a single camera to capture signals to recover multi-pixel vibrations. One alternative embodiment employs two cameras and homodyne optical I/Q detection. A second alternative embodiment uses a single camera and temporally phase shifted local oscillator to also carry out homodyne optical I/Q detection. The disclosed sensors are capable of scalability to large numbers of pixels and can capture vibration frequencies over a wide range.

Growing community of inventors

Berthoud, CO, United States of America

Philip Gatt