Rotational geometric phase hologram with application for fabricating geometric phase optical element

    公开(公告)号:US10983262B2

    公开(公告)日:2021-04-20

    申请号:US16136371

    申请日:2018-09-20

    摘要: A rotational geometric phase hologram has geometric phase optical elements (GPOEs) serially cascaded along a common optical axis to form a GPOE cascade used for receiving a linearly-polarized light beam and generating output light beams at an exit surface of the last GPOE. Interference occurred in the output light beams creates a polarization interference pattern on the exit surface. A photoalignment substrate, when positioned in close proximity to the exit surface, records the pattern. Advantageously, each GPOE is rotatable about the common optical axis. Respective rotation angles of the GPOEs are determined according to a spatially-varying linear polarization orientation distribution selected to be generated for the polarization interference pattern. Particularly, the respective rotation angles are reconfigurable to provide the periodicity required for the spatially-varying linear polarization orientation distribution over a range of allowed periodicities while keeping the periodicity of spatially-varying optic axis orientation distribution of each GPOE to be fixed.

    Advanced multi-gain calibration for direct modulation synthesizer

    公开(公告)号:US10862427B1

    公开(公告)日:2020-12-08

    申请号:US16857804

    申请日:2020-04-24

    发明人: Tat Fu Chan

    摘要: A two-point modulation Phase-Locked Loop (PLL) has a dual-input Voltage-Controlled Oscillator (VCO). A digital data modulation signal is combined with a carrier and input to a feedback divider. The data modulation signal is also input to an offset Digital-to-Analog Converter (DAC) to generate an analog voltage to a second input of the VCO. The loop path through the VCO has a higher gain than the DAC path through the VCO, which has better linearity. A calibration unit divides the VCO output and counts pulses. The offset DAC has a data input and a gain input. During calibration, the data input of the DAC is set to minimum and then maximum values and VCO output pulses counted, and repeated for two values of the gain input to the DAC. From the four counts a K(DAC) calculator calculates the calibrated gain to apply to the gain input of the offset DAC.

    APPARATUS AND METHOD OF HIGH DIMENSIONAL DATA ANALYSIS IN REAL-TIME

    公开(公告)号:US20200293945A1

    公开(公告)日:2020-09-17

    申请号:US16354207

    申请日:2019-03-15

    摘要: A method of high dimensional data analysis in real-time comprising executing dimension-reducing an input historical data set under a t-SNE model and determining from the resulting dimension-reduced data set a recent; further dimension-reducing the recent group data set under a PCA model; statistical analyzing the further dimension-reduced data set to determine a threshold group for distinguishing abnormal data from normal ones in a real-time data stream. The method may further include training a classifier using the abnormal or normal data set for predicting anomaly in the real-time data source system. Alternatively, a discrepancy training data set is computed from one of the normal and abnormal data sets and be used to train one of independent normal and abnormal data regression models; with the other one trained by transfer learning based on the trained one. The trained regression models are then used to predict discrepancy values.

    Silicon-carbide shielded-MOSFET embedded with a trench Schottky diode and heterojunction gate

    公开(公告)号:US10777689B1

    公开(公告)日:2020-09-15

    申请号:US16657376

    申请日:2019-10-18

    摘要: A shielded Schottky heterojunction power transistor is made from a Silicon-Carbide (SiC) wafer with SiC epitaxial layers including a N+ source and a Silicon N-epitaxial layer under the gate with higher channel mobility than SiC. The bulk of the wafer is a N+ SiC drain contacted by backside metal. A trench is formed between heterojunction transistors. Metal contacting the N+ source is extended into the trench to form a Schottky diode with the N-SiC substrate. P+ taps on the sides of the trench connect the metal to a P-SiC body diode under the heterojunction gate, and also prevent the Schottky metal from directly contacting the P body diode. Buried P pillars with P+ pillar caps are formed under the trench Schottky diode and under the heterojunction transistors. The P pillars provide shielding by balancing charge with the N substrate, acting as dielectrics to reduce the E-field above the pillars.

    Single-temperature-point temperature sensor sensitivity calibration

    公开(公告)号:US10677664B1

    公开(公告)日:2020-06-09

    申请号:US16416390

    申请日:2019-05-20

    IPC分类号: G01K15/00

    摘要: A single-temperature-point temperature-sensitivity sensor assumes that all sensitivity lines converge at absolute zero temperature, so during calibration measurement is needed at only one temperature. A sensor output voltage is generated by current from a mirrored current source flowing through a variable resistor. During calibration, the resistance of the variable resistor and the mirror ratio of the mirrored current source are adjusted. An error amplifier compares voltages generated by unit currents generated by unit current sources to adjust the unit current sources and the mirrored current source. Each unit current flows through a grounded-base PNP transistor. A switchable PNP transistor is in parallel with one of the grounded-base PNP transistors and has its base switched on and off to adjust the PNP current for two measurements. The difference between the two measurements is compared to a calibration target to adjust the variable resistor and mirror ratio during calibration at a single temperature.

    Semiconductor Device Modeling Using Input Pre-Processing and Transformed Targets for Training a Deep Neural Network

    公开(公告)号:US20190385047A1

    公开(公告)日:2019-12-19

    申请号:US16011787

    申请日:2018-06-19

    发明人: Yuan LEI Xiao HUO

    IPC分类号: G06N3/063 G06N3/10 G06N3/08

    摘要: A deep neural network models semiconductor devices. Measurements of test transistors are gathered into training data including gate and drain voltages and transistor width and length, and target data such as the drain current measured under the input conditions. The training data is converted by an input pre-processor that can apply logarithms of the inputs or perform a Principal Component Analysis (PCA). Rather than use measured drain current as the target when training the deep neural network, a target transformer transforms the drain current into a transformed drain current, such as a derivative of the drain current with respect to gate or drain voltages, or a logarithm of the derivative. Weights in the deep neural network are adjusted during training by comparing the deep neural network's output to the transformed drain current and generating a loss function that is minimized over the training data.

    Duty cycle controller with calibration circuit

    公开(公告)号:US10418978B1

    公开(公告)日:2019-09-17

    申请号:US16253446

    申请日:2019-01-22

    IPC分类号: H03K3/017

    摘要: An integrator in a duty-cycle adjustment circuit has an adjustable charging current provided by a switched current-source array in response to configuration signals from the calibration logic. The integrator's ramp voltage is compared to a threshold voltage by a comparator to generate an output clock. A tunable voltage reference generates a reference voltage that can be tuned by configuration signals from the calibration logic. The reference voltage is divided by a tunable voltage divider, which selects different fractions of the reference voltage for use as the threshold voltage. During calibration, calibration logic repeatedly raises the reference voltage or reduces the charging current from the switched current-source array until a peak voltage of the ramp voltage equals the reference voltage, when a zero duty onset detector detects that the output clock has stopped pulsing. The configuration signals at the zero duty onset condition are stored and used for normal operation.

    FLEXIBLE INTEGRATING RECOGNITION AND SEMANTIC PROCESSING

    公开(公告)号:US20190156156A1

    公开(公告)日:2019-05-23

    申请号:US16191501

    申请日:2018-11-15

    IPC分类号: G06K9/62 G06K9/46 G06K9/72

    摘要: A method for character recognition and semantic for natural language processing comprising extracting a sequence of feature vectors from a sequence of input character images by a convolutional neural network (CNN) feature extractor. The sequence of feature vectors comprises a plurality of feature vectors, each feature vector representing an approximate-match of its corresponding input character in the sequence of input character images. The method further comprises applying a sequential classifier sequentially as a sliding window of a size of a plurality consecutive feature vectors upon the sequence of feature vectors from a first feature vector in the sequence of feature vectors to the last feature vector in the sequence of feature vectors; and recognizing an output character for a targeted feature vector among the applied-upon consecutive feature vectors within the sliding window as it is sliding across the sequence of feature vectors.

    Compact device for sensing a liquid with energy harvesting from liquid motion

    公开(公告)号:US10161861B2

    公开(公告)日:2018-12-25

    申请号:US15377643

    申请日:2016-12-13

    摘要: A compact device useful for measuring an absorption spectrum of a liquid, such as water with organic contaminants, is provided. The device comprises an array of light emitting diodes (LEDs) each emitting light with a unique spectral peak. A reflector shaped as a half ellipsoid reflects the emitted light to form a reference beam. The reflector has an opening to allow part of the emitted light to form a measurement beam after passing through the liquid. Two photodetectors measure the reference beam and the measurement beam to give a reference intensity and a measured intensity, respectively. The LEDs sequentially emit showers of light one-by-one, giving plural pairs of reference and measured intensities for estimating the absorption spectrum. The device receives energy from a separate power-providing device through wireless power transfer. The power-providing device harvests motional energy of the flowing liquid to generate electrical energy.