Patent application number | Description | Published |
20090185806 | Broadcasting arrayed waveguide - The invention is a data transmission device that includes: an input Free Propagation Region (FPR) receiving a multi-wavelength signal and a single-wavelength signal, and two sets of arrayed waveguides coupled to the input FPR to carry the multi-wavelength signal and the single-wavelength signal, respectively. The arrayed waveguides demultiplex the multi-wavelength signal and create copies of the single-wavelength signal. The output plane of an output FPR receives the demultiplexed wavelengths and the copies of the single-wavelength signal such that one of the demultiplexed wavelengths and one of the copies of the single-wavelength signal focus onto the same position on the output plane. The device allows data (e.g., video stream) to be broadcast to all subscribers in a Wavelength-Division-Multiplexed Passive Optical Network (WDM-PON) architecture. A multicasting apparatus can be implemented by using a plurality of these devices and using different wavelengths for the single-wavelength signal for the different devices. | 07-23-2009 |
20090214170 | REFLECTIVE PLANAR LIGHTWAVE CIRCUIT WAVEGUIDE - A method of making a planar lightwave circuit (PLC) waveguide capable of being integrated with a surface-mounted component is presented. The method entails etching a silicon substrate to form a slanted wall, forming a nonreflective waveguide portion on the silicon substrate, and depositing a reflective layer on the slanted wall. Light travels through the nonreflective waveguide portion in substantially a first direction, and the light from the nonreflective waveguide portion strikes the reflective layer to be redirected in a second direction. The second direction may be the direction toward the surface-mounted component. A PLC waveguide device made with the above method is also presented. | 08-27-2009 |
20100025361 | REFLECTIVE PLANAR LIGHTWAVE CIRCUIT WAVEGUIDE - A method of making a planar lightwave circuit (PLC) waveguide capable of being integrated with a surface-mounted component is presented. The method entails etching a silicon substrate to form a slanted wall, forming a nonreflective waveguide portion on the silicon substrate, and depositing a reflective layer on the slanted wall. Light travels through the nonreflective waveguide portion in substantially a first direction, and the light from the nonreflective waveguide portion strikes the reflective layer to be redirected in a second direction. The second direction may be the direction toward the surface-mounted component. A PLC waveguide device made with the above method is also presented. | 02-04-2010 |
Patent application number | Description | Published |
20100067357 | MAGNETIC RECORDING DISK DRIVE WITH ROTATIONAL VIBRATION COMPENSATION HAVING ADAPTIVE OPTIMIZATION OF VIBRATION SENSOR GAINS - A disk drive and a method for operating the disk drive compensates for rotational vibration (RV) by adaptively modifying the gains of two separate linear vibration sensors so the sensor gains are optimal under any given condition. The two sensors provide two signals S | 03-18-2010 |
20110085260 | DISK DRIVE AND SERVO CONTROL METHOD FOR THE DISK DRIVE THAT IS RESPONSIVE TO VIBRATION - A disk drive. The disk drive includes an acceleration sensor, a servo controller, a detection determiner, and a handling processor. The acceleration sensor has an associated resonant frequency. The servo controller is configured to perform servo control for head positioning using frequency components that are obtained by cutting off frequency components including the resonant frequency from output of the acceleration sensor. The detection determiner is configured to detect a frequency band including the resonant frequency from the output of the acceleration sensor to determine whether a magnitude of a voltage amplitude of the frequency band is outside of a specified range. The handling processor is configured to execute a corresponding handling operation if the detection determiner determines that the magnitude of the voltage amplitude of the frequency band is outside of the specified range. | 04-14-2011 |
20130033777 | SYSTEM AND METHOD OF SYNCHRONIZED WRITING ON BIT PATTERNED MEDIA WITH READ-WRITE OFFSET - A system and method of establishing write timing in a disk drive using bit patterned media and a magnetic head with read-write offset in which servoing and writing occur on different tracks with timing offsets. Initially, the distance between the servoing and writing tracks is determined for each track/head position in accordance with head geometry and skew angle. The relative timing errors are then measured by iteratively writing data at timing offset increments to determine the optimal timing offset for the servoing/writing track pair, and then writing the offset to sync fields on the servoing tracks of the disk. | 02-07-2013 |
20130141811 | Disk drive with write clock frequency compensation for external vibration disturbance - A disk drive is described that uses a vibration sensor to generate a compensating feed-forward control signal to synchronize the write clock frequency with the modulated data island frequency. A linear vibration sensor is positioned with its sensitivity axis aligned with the tangential direction of a track at the radial position of the write head. The tangential component of the external linear vibration is measured by the sensor. The feed-forward control signal derived from the linear vibration sensor modifies the control voltage input to VCO (voltage controlled oscillator) in the write clock generator to adjust the write clock frequency to compensate for the modulated data island frequency caused by the tangential component of the linear vibration. | 06-06-2013 |
20130250451 | MAGNETIC RECORDING DISK DRIVE WITH THREE SENSORS FOR ROTATIONAL AND LINEAR VIBRATION COMPENSATION - A magnetic recording disk drive has three vibration sensors mounted to the disk drive base to provide feedforward vibration compensation signals. First and second spaced-apart sensors are aligned generally parallel to a radius from the disk rotational axis to a head position on the disk between the inside diameter position (h | 09-26-2013 |