Patent application number | Description | Published |
20080253711 | High speed optical phase modulator - An optical device includes a phase modulator having a waveguide on a substrate. The phase modulator also includes an n-type region having a proximity to a p-type region that causes formation of a depletion region when a bias is not applied to the modulator. The depletion region is at least partially positioned in the light signal carrying region of the waveguide. The phase modulator is tuned by applying a reverse bias to the phase modulator. The reverse bias changes the size of the depletion region. | 10-16-2008 |
20100085992 | Arbitrary Optical Waveform Generation Utilizing Optical Phase-Locked Loops - This invention relates to opto-electronic systems using semiconductor lasers driven by optical phase-locked loops that control the laser's optical phase and frequency. Feedback control provides a means for precise, wideband control of optical frequency and phase, augmented further by four wave mixing stages and digitally stitched independent optical waveforms for enhanced tunability. | 04-08-2010 |
20120262721 | Arbitrary Optical Waveform Generation Utilizing Optical Phase-Locked Loops - This invention relates to opto-electronic systems using semiconductor lasers driven by optical phase-locked loops that control the laser's optical phase and frequency. Feedback control provides a means for precise, wideband control of optical frequency and phase, augmented further by four wave mixing stages and digitally stitched independent optical waveforms for enhanced tunability. | 10-18-2012 |
20130044311 | THREE-DIMENSIONAL TOMOGRAPHIC IMAGING CAMERA - A detection apparatus and method for FMCW LIDAR employ signals whose frequencies are modified so that low-cost and low-speed photodetector arrays, such a can be employed for range detection. The LIDAR is includes a single mode swept frequency laser (SFL), whose optical frequency is varied with time, as a result of which, a target beam reflected back by the target is shifted in frequency from a reference beam by an amount that is proportional to the relative range z to the target. The reflected target beam is combined with the reference beam and detected by the photodetector array. The difference between the frequencies of the reflected target beam and the reference beam is reduced to a level that is within the bandwidth of the photodetector array by first modulating the target and/or reference beam. | 02-21-2013 |
20130044770 | FREQUENCY-CHIRPED SEMICONDUCTOR DIODE LASER PHASE-LOCKED OPTICAL SYSTEM - A chirped diode laser (ChDL) is employed for seeding optical amplifiers and/or dissimilar optical paths, which simultaneously suppresses stimulated Brillouin scattering (SBS) and enables coherent combination. The seed spectrum will appear broadband to suppress the SBS, but the well-defined chirp will have the coherence and duration to allow the active phasing of multiple amplifiers and/or dissimilar optical paths. The phasing is accomplished without optical path-length matching by interfering each amplifier output with a reference, processing the resulting signal with a phase lock loop, and using the error signal to drive an acousto-optic frequency shifter at the front end of each optical amplifier and/or optical path. | 02-21-2013 |
20140104593 | THREE-DIMENSIONAL TOMOGRAPHIC IMAGING CAMERA BASED ON COMPRESSIVE SENSING - A detection apparatus and method for FMCW LIDAR employ signals that are modified so that low-cost and low-speed photodetector arrays, such as CCD or CMOS cameras, can be employed for range detection. The LIDAR is designed to measure the range to one or more targets and includes a single mode swept frequency laser (SFL), whose optical frequency is varied with time, as a result of which, a target beam which is reflected back by the one or more targets is shifted in frequency from a reference beam by an amount that is proportional to the relative range to the one or more targets. The reflected target beam(s) is/are combined with the reference beam and detected by the photodetector array. In the case of a sparse number of targets to be detected, Compressive Sensing (CS) techniques can be employed by a processor to reduce the number of measurements necessary to determine the range of each target. | 04-17-2014 |
20150177380 | THREE-DIMENSIONAL TOMOGRAPHIC IMAGING CAMERA - A detection apparatus and method for FMCW LIDAR employ signals whose frequencies are modified so that low-cost and low-speed photodetector arrays, such as CCD or CMOS cameras, can be employed for range detection. The LIDAR is designed to measure the range z to a target and includes a single mode swept frequency laser (SFL), whose optical frequency is varied with time, as a result of which, a target beam which is reflected back by the target is shifted in frequency from a reference beam by an amount that is proportional to the relative range z to the target. The reflected target beam is combined with the reference beam and detected by the photodetector array. By first modulating at least one of the target and reference beams such that the difference between the frequencies of the reflected target beam and the reference beam is reduced to a level that is within the bandwidth of the photodetector array, the need for high-speed detector arrays for full-field imaging is obviated. | 06-25-2015 |