Patents Assigned to Lightmatter, Inc
  • Publication number: 20220374575
    Abstract: Electronic-photonic packages and related fabrication methods are described. A package may include a plurality of photonic integrated circuits (PICs), where each PIC comprises a photonic accelerator configured to perform matrix multiplication in the optical domain. The package may further include an application specific integrated circuit (ASIC) configured to control at least one of the photonic accelerators. The package further includes an interposer. The plurality of PICs are coupled to a first side of the interposer and the ASIC is coupled to a second side of the interposer opposite the first side. A first thermally conductive member in thermal contact with at least one of the PICs. The first thermally conductive member may include a heat spreader. A second thermally conductive member in thermal contact with the ASIC. The second thermally conductive member may include a lid.
    Type: Application
    Filed: May 19, 2022
    Publication date: November 24, 2022
    Applicant: Lightmatter, Inc.
    Inventors: Carl Ramey, Nicholas C. Harris, Hamid Eslampour
  • Publication number: 20220366308
    Abstract: Methods and apparatus for training a matrix-based differentiable program using a photonics-based processor. The matrix-based differentiable program includes at least one matrix-valued variable associated with a matrix of values in a Euclidean vector space. The method comprises configuring components of the photonics-based processor to represent the matrix of values as an angular representation, processing, using the components of the photonics-based processor, training data to compute an error vector, determining in parallel, at least some gradients of parameters of the angular representation, wherein the determining is based on the error vector and a current input training vector, and updating the matrix of values by updating the angular representation based on the determined gradients.
    Type: Application
    Filed: July 13, 2022
    Publication date: November 17, 2022
    Applicant: Lightmatter, Inc.
    Inventors: Tomo Lazovich, Darius Bunandar, Nicholas C. Harris, Martin B.Z. Forsythe
  • Patent number: 11494541
    Abstract: Aspects relate to a photonic processing system, an integrated circuit, and a method of operating an integrated circuit to control components to modulate optical signals. A photonic processing system, comprising: a photonic integrated circuit comprising: a first electrically-controllable photonic component electrically coupling an input pin to a first output pin; and a second electrically-controllable photonic component electrically coupling the input pin to a second output pin.
    Type: Grant
    Filed: January 14, 2021
    Date of Patent: November 8, 2022
    Assignee: Lightmatter, Inc.
    Inventors: Carl Ramey, Darius Bunandar, Nicholas C. Harris
  • Patent number: 11475367
    Abstract: Methods and apparatus for training a matrix-based differentiable program using a photonics-based processor. The matrix-based differentiable program includes at least one matrix-valued variable associated with a matrix of values in a Euclidean vector space. The method comprises configuring components of the photonics-based processor to represent the matrix of values as an angular representation, processing, using the components of the photonics-based processor, training data to compute an error vector, determining in parallel, at least some gradients of parameters of the angular representation, wherein the determining is based on the error vector and a current input training vector, and updating the matrix of values by updating the angular representation based on the determined gradients.
    Type: Grant
    Filed: June 29, 2020
    Date of Patent: October 18, 2022
    Assignee: Lightmatter, Inc.
    Inventors: Tomo Lazovich, Darius Bunandar, Nicholas C. Harris, Martin B. Z. Forsythe
  • Publication number: 20220317378
    Abstract: Methods and apparatus for tuning a photonics-based component. An opto-electrical detector is configured to output an electrical signal based on a measurement of light intensity of the photonics-based component, the light intensity being proportional to an amount of detuning of the photonics-based component. Analog-to-digital conversion (ADC) circuitry is configured to output a digital signal based on the electrical signal output from the opto-electrical detector. Feedback control circuitry is configured to tune the photonics-based component based, at least in part, on the digital signal output from the ADC circuitry.
    Type: Application
    Filed: June 17, 2022
    Publication date: October 6, 2022
    Applicant: Lightmatter, Inc.
    Inventors: Carlos Dorta-Quinones, Carl Ramey, Omer Ozgur Yildirim, Chithira Ravi, Shashank Gupta, Nicholas C. Harris
  • Publication number: 20220261645
    Abstract: Methods and systems for training neural networks using low-bitwidth accelerators are described. The methods described herein use moment-penalization functions. For example, a method comprises producing a modified data set by training a neural network using a moment-penalization function and the data set. The moment-penalization function is configured to penalize a moment associated with the neural network. Training the neural network in turn comprises quantizing the data set to obtain a fixed-point data set so that the fixed-point data set represents the data set in a fixed-point representation, and passing the fixed-point data set through an analog accelerator. The inventors have recognized that training a neural network using a modified objective function augments the accuracy and robustness of the neural network notwithstanding the use of low-bitwidth accelerators.
    Type: Application
    Filed: February 15, 2022
    Publication date: August 18, 2022
    Applicant: Lightmatter, Inc.
    Inventors: Nicholas Dronen, Tyler J. Kenney, Tomo Lazovich, Ayon Basumallik, Darius Bunandar
  • Patent number: 11409045
    Abstract: Methods and apparatus for tuning a photonics-based component. An opto-electrical detector is configured to output an electrical signal based on a measurement of light intensity of the photonics-based component, the light intensity being proportional to an amount of detuning of the photonics-based component. Analog-to-digital conversion (ADC) circuitry is configured to output a digital signal based on the electrical signal output from the opto-electrical detector. Feedback control circuitry is configured to tune the photonics-based component based, at least in part, on the digital signal output from the ADC circuitry.
    Type: Grant
    Filed: July 1, 2020
    Date of Patent: August 9, 2022
    Assignee: Lightmatter, Inc.
    Inventors: Carlos Dorta-Quinones, Carl Ramey, Omer Ozgur Yildirim, Chithira Ravi, Shashank Gupta, Nicholas C. Harris
  • Patent number: 11398871
    Abstract: Systems and methods for performing signed matrix operations using a linear photonic processor are provided. The linear photonic processor is formed as an array of first amplitude modulators and second amplitude modulators, the first amplitude modulators configured to encode elements of a vector into first optical signals and the second amplitude modulators configured to encode a product between the vector elements and matrix elements into second optical signals. An apparatus may be used to implement a signed value of an output of the linear processor. The linear photonic processor may be configured to perform matrix-vector and/or matrix-matrix operations.
    Type: Grant
    Filed: July 28, 2020
    Date of Patent: July 26, 2022
    Assignee: Lightmatter, Inc.
    Inventors: Darius Bunandar, Nicholas C. Harris, Michael Gould, Carl Ramey, Tomo Lazovich
  • Publication number: 20220229634
    Abstract: A photonic processor uses light signals and a residue number system (RNS) to perform calculations. The processor sums two or more values by shifting the phase of a light signal with phase shifters and reading out the summed phase with a coherent detector. Because phase winds back every 2? radians, the photonic processor performs addition modulo 2?. A photonic processor may use the summation of phases to perform dot products and correct erroneous residues. A photonic processor may use the RNS in combination with a positional number system (PNS) to extend the numerical range of the photonic processor, which may be used to accelerate homomorphic encryption (HE)-based deep learning.
    Type: Application
    Filed: December 6, 2021
    Publication date: July 21, 2022
    Applicant: Lightmatter, Inc.
    Inventors: Eric Hein, Ayon Basumallik, Nicholas C. Harris, Darius Bunandar, Cansu Demirkiran
  • Patent number: 11367711
    Abstract: A memory device is described. The memory device comprises a plurality of stacked memory layers, wherein each of the plurality of stacked memory layers comprises a plurality of memory cells. The memory device further comprises an optical die bonded to the plurality of stacked memory layers and in electrical communication with the stacked memory layers through one or more interconnects. The optical die comprises an optical transceiver, and a memory controller configured to control read and/or write operations of the stacked memory layers. The optical die may be positioned at one end of the plurality of stacked memory layers. The one or more interconnects may comprise one or more through silicon vias (TSV). The plurality of memory cells may comprise a plurality of solid state memory cells. The memory devices described herein can enable all-to-all, point-to-multipoint and ring architectures for connecting logic units with memory devices.
    Type: Grant
    Filed: April 30, 2019
    Date of Patent: June 21, 2022
    Assignee: Lightmatter, Inc.
    Inventors: Nicholas C. Harris, Carl Ramey
  • Publication number: 20220172052
    Abstract: Described herein are techniques of training a machine learning model and performing inference using an analog processor. Some embodiments mitigate the loss in performance of a machine learning model resulting from a lower precision of an analog processor by using an adaptive block floating-point representation of numbers for the analog processor. Some embodiments mitigate the loss in performance of a machine learning model due to noise that is present when using an analog processor. The techniques involve training the machine learning model such that it is robust to noise.
    Type: Application
    Filed: November 29, 2021
    Publication date: June 2, 2022
    Applicant: Lightmatter, Inc.
    Inventors: Darius Bunandar, Ludmila Levkova, Nicholas Dronen, Lakshmi Nair, David Widemann, David Walter, Martin B.Z. Forsythe, Tomo Lazovich, Ayon Basumallik, Nicholas C. Harris
  • Publication number: 20220155996
    Abstract: Aspects of the present disclosure provide an aligned storage strategy for stripes within a long vector for a vector processor, such that the extra computation needed to track strides between input stripes and output stripes may be eliminated. As a result, the stripe locations are located in a more predictable memory access pattern such that memory access bandwidth may be improved and the tendency for memory error may be reduced.
    Type: Application
    Filed: November 15, 2021
    Publication date: May 19, 2022
    Applicant: Lightmatter, Inc.
    Inventors: Nicholas Moore, Gongyu Wang, Bradley Dobbie, Tyler J. Kenney, Ayon Basumallik
  • Publication number: 20220156469
    Abstract: Parallelization and pipelining techniques that can be applied to multi-core analog accelerators are described. The techniques descried herein improve performance of matrix multiplication (e.g., tensor-tensor multiplication, matrix-matrix multiplication or matrix-vector multiplication). The parallelization and pipelining techniques developed by the inventors and described herein focus on maintaining a high utilization of the processing cores. A representative processing systemin includes an analog accelerator, a digital processor, and a controller. The controller is configured to control the analog accelerator to output data using linear operations and to control the digital processor to perform non-linear operations based on the output data.
    Type: Application
    Filed: November 15, 2021
    Publication date: May 19, 2022
    Applicant: Lightmatter, Inc.
    Inventors: Gongyu Wang, Cansu Demirkiran, Nicholas Moore, Ayon Basumallik, Darius Bunandar
  • Publication number: 20220147280
    Abstract: Aspects of the present disclosure are directed to an efficient data transfer strategy in which data transfer is scheduled based on a prediction of the internal memory utilization due to computational workload throughout its runtime. According to one aspect, the DMA transfer may be performed opportunistically: whenever internal buffer memory is available and the additional internal memory usage due to DMA transfer isn't interfering with the processor's ability to complete the workload. In some embodiments, an opportunistic transfer schedule may be found by solving an optimization problem.
    Type: Application
    Filed: November 9, 2021
    Publication date: May 12, 2022
    Applicant: Lightmatter, Inc.
    Inventors: Darius Bunandar, Cansu Demirkiran, Gongyu Wang, Nicholas Moore, Ayon Basumallik
  • Publication number: 20220100973
    Abstract: Techniques for computing matrix operations for arbitrarily large matrices on a finite-sized hybrid analog-digital matrix processor are described. Techniques for gain adjustment in a finite-sized hybrid analog-digital matrix processor are described which enable the system to obtain higher energy efficiencies, greater physical density and improved numerical accuracy. In some embodiments, these techniques enable maximization of the predictive accuracy of a GEMM-based convolutional neural network using low-precision data representations.
    Type: Application
    Filed: December 8, 2021
    Publication date: March 31, 2022
    Applicant: Lightmatter, Inc.
    Inventors: Tyler J. Kenney, Martin B. Z. Forsythe, Tomo Lazovich, Darius Bunandar
  • Publication number: 20220094443
    Abstract: Aspects relate to a photonic processing system, a photonic processor, and a method of performing matrix-vector multiplication. An optical encoder may encode an input vector into a first plurality of optical signals. A photonic processor may receive the first plurality of optical signals; perform a plurality of operations on the first plurality of optical signals, the plurality of operations implementing a matrix multiplication of the input vector by a matrix; and output a second plurality of optical signals representing an output vector. An optical receiver may detect the second plurality of optical signals and output an electrical digital representation of the output vector.
    Type: Application
    Filed: December 1, 2021
    Publication date: March 24, 2022
    Applicant: Lightmatter, Inc.
    Inventors: Darius Bunandar, Nicholas C. Harris, Carl Ramey
  • Patent number: 11281068
    Abstract: A nano-opto-electro-mechanical System (NOEMS) phase shifter is described. The NOEMS may include a multi-slot waveguide structure suspended in air. The multi-slot waveguide structure may include three or more waveguides separated from each other by slots. The width of the slots may be sufficiently small to support slot modes, where a substantial portion of the mode energy is within the slots. For example, the slots may have widths less than 200 nm or less than 100 nm. The multi-slot waveguide structure may be disposed in a trench formed though the upper cladding of a substrate. An undercut may be formed under the multi-slot waveguide structure to enable free motion of the structure. NOEMS phase modulators of the types described herein may be used in connection with photonic processing systems, telecom/datacom systems, analog systems, etc.
    Type: Grant
    Filed: November 24, 2020
    Date of Patent: March 22, 2022
    Assignee: Lightmatter, Inc.
    Inventor: Michael Gould
  • Publication number: 20220085777
    Abstract: Low-noise optical differential receivers are described. Such differential receivers may include a differential amplifier having first and second inputs and first and second outputs, and four photodetectors. A first and a second of such photodetectors are coupled to the first input of the differential amplifier, and a third and a fourth of such photodetectors are coupled to the second input of the differential amplifier. The anode of the first photodetector and the cathode of the second photodetector are coupled to the first input of the differential amplifier. The cathode of the third photodetector and the anode of the fourth photodetector are coupled to the second input of the differential amplifier. The optical receiver may involve two stages of signal subtraction, which may significantly increase noise immunity.
    Type: Application
    Filed: October 26, 2021
    Publication date: March 17, 2022
    Applicant: Lightmatter, Inc.
    Inventors: Nicholas C. Harris, Michael Gould, Omer Ozgur Yildirim
  • Patent number: 11256029
    Abstract: Photonic packages are described. One such photonic package includes a photonic chip, an application specific integrated circuit, and optionally, an interposer. The photonic chip includes photonic microelectromechanical system (MEMS) devices. A photonic package may include a material layer patterned to include recesses. The recesses are aligned with the photonic MEMS devices so as to form enclosed cavities around the photonic MEMS devices. This arrangement preserves the integrity of the photonic MEMS devices.
    Type: Grant
    Filed: October 15, 2019
    Date of Patent: February 22, 2022
    Assignee: Lightmatter, Inc.
    Inventors: Sukeshwar Kannan, Carl Ramey, Michael Gould, Nicholas C. Harris
  • Publication number: 20220043474
    Abstract: Systems and methods for performing matrix operations using a path-number balanced optical network are provided. The optical network is formed as an array including active optical components and passive optical components arranged at a substantially central location of the array. The optical network includes at least NM active optical components which are used to implement a first matrix of any size N×M by embedding the first matrix in a second matrix of a larger size. The optical network performs matrix-vector and matrix-matrix operations by propagating one or more pluralities of optical signals corresponding to an input vector through the optical network.
    Type: Application
    Filed: October 21, 2021
    Publication date: February 10, 2022
    Applicant: Lightmatter, Inc.
    Inventors: Darius Bunandar, Martin B.Z. Forsythe, Michael Gould, Tomo Lazovich