Patents by Inventor Yu-Lung Lo

Yu-Lung Lo has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 11745267
    Abstract: An additive manufacturing (AM) method is provided. The method includes performing a laser powder bed fusion (L-PBF) process on the powder layer. Then, a first surface roughness value of the powder layer after the L-PBF process is obtained to generate a first surface profile. An absorptivity and a set of re-melting process parameters data are used to perform a heat transfer simulation. A second surface profile of the powder layer after laser re-melting is obtained by using the first surface profile and a low-pass filter. Then, the set of re-melting process parameters data is adjusted iteratively to perform the heat transfer simulation until a second surface roughness value predicted from the second surface profile is smaller than or equal to a surface roughness threshold, thereby obtaining optimal values of re-melting process parameters for performing a re-melting process to reduce a surface roughness of a powder layer after the L-PBF process.
    Type: Grant
    Filed: June 24, 2021
    Date of Patent: September 5, 2023
    Assignee: NATIONAL CHENG KUNG UNIVERSITY
    Inventors: Hong-Chuong Tran, Yu-Lung Lo, Haw-Ching Yang, Fan-Tien Cheng
  • Patent number: 11679565
    Abstract: An additive manufacturing (AM) method includes using an AM tool to fabricate a plurality of workpiece products; measuring qualities of the first workpiece products respectively; performing a temperature measurement on each of the melt pools on the powder bed during a fabrication of each of the workpiece products; performing photography on each of the melt pools on the powder bed during the fabrication of each of the workpiece products; extracting a length and a width of each of the melt pools; performing a melt-pool feature processing operation; building a conjecture model by using a plurality of sets of first process data and the actual metrology values of the first workpiece products in accordance with a prediction algorithm; and predicting a virtual metrology value of the second workpiece product by using the conjecture model based on a set of second process data.
    Type: Grant
    Filed: June 6, 2022
    Date of Patent: June 20, 2023
    Assignee: NATIONAL CHENG KUNG UNIVERSITY
    Inventors: Haw-Ching Yang, Yu-Lung Lo, Hung-Chang Hsiao, Shyh-Hau Wang, Min-Chun Hu, Chih-Hung Huang, Fan-Tien Cheng
  • Patent number: 11673339
    Abstract: An additive manufacturing (AM) method includes using an AM tool to fabricate a plurality of workpiece products; measuring qualities of the first workpiece products respectively; performing a temperature measurement on each of the melt pools on the powder bed; performing photography on each of the melt pools on the powder bed; extracting a length and a width of each of the melt pools; performing a melt-pool feature processing operation; first converting each of the workspace images to a gray level co-occurrence matrix (GLCM); building a conjecture model by using a plurality of sets of first process data and the actual metrology values of the first workpiece products in accordance with a prediction algorithm; and predicting a virtual metrology value of the second workpiece product by using the conjecture model based on a set of second process data.
    Type: Grant
    Filed: June 17, 2022
    Date of Patent: June 13, 2023
    Assignee: NATIONAL CHENG KUNG UNIVERSITY
    Inventors: Haw-Ching Yang, Yu-Lung Lo, Hung-Chang Hsiao, Shyh-Hau Wang, Min-Chun Hu, Chih-Hung Huang, Fan-Tien Cheng
  • Publication number: 20220314552
    Abstract: An additive manufacturing (AM) method includes using an AM tool to fabricate a plurality of workpiece products; measuring qualities of the first workpiece products respectively; performing a temperature measurement on each of the melt pools on the powder bed; performing photography on each of the melt pools on the powder bed; extracting a length and a width of each of the melt pools; performing a melt-pool feature processing operation; first converting each of the workspace images to a gray level co-occurrence matrix (GLCM); building a conjecture model by using a plurality of sets of first process data and the actual metrology values of the first workpiece products in accordance with a prediction algorithm; and predicting a virtual metrology value of the second workpiece product by using the conjecture model based on a set of second process data.
    Type: Application
    Filed: June 17, 2022
    Publication date: October 6, 2022
    Inventors: Haw-Ching YANG, Yu-Lung LO, Hung-Chang HSIAO, Shyh-Hau WANG, Min-Chun HU, Chih-Hung HUANG, Fan-Tien CHENG
  • Publication number: 20220297383
    Abstract: An additive manufacturing (AM) method includes using an AM tool to fabricate a plurality of workpiece products; measuring qualities of the first workpiece products respectively; performing a temperature measurement on each of the melt pools on the powder bed during a fabrication of each of the workpiece products; performing photography on each of the melt pools on the powder bed during the fabrication of each of the workpiece products; extracting a length and a width of each of the melt pools; performing a melt-pool feature processing operation; building a conjecture model by using a plurality of sets of first process data and the actual metrology values of the first workpiece products in accordance with a prediction algorithm; and predicting a virtual metrology value of the second workpiece product by using the conjecture model based on a set of second process data.
    Type: Application
    Filed: June 6, 2022
    Publication date: September 22, 2022
    Inventors: Haw-Ching Yang, Yu-Lung Lo, Hung-Chang Hsiao, Shyh-Hau Wang, Min-Chun Hu, Chih-Hung Huang, Fan-Tien Cheng
  • Patent number: 11383446
    Abstract: An additive manufacturing (AM) system, an AM method, and an AM feature extraction method are provided. The AM system includes an AM tool, a product metrology system, an in-situ metrology system, a virtual metrology (VM) system, a compensator, a track planner, a controller, a simulator and an augmented reality (AR) device. The simulator is used to find feasible parameter ranges, while the AR device is used to support operations and maintenance of the AM tool. The product metrology system, the in-situ metrology system and the VM system are integrated to estimate the variation of material on a powder bed of the AM tool. The compensator is used for compensating the process variation by adjusting process parameters. The product metrology system is used to measure the quality of products. The in-situ metrology system is used to collect features of melt pools on the powder bed.
    Type: Grant
    Filed: October 2, 2019
    Date of Patent: July 12, 2022
    Assignee: NATIONAL CHENG KUNG UNIVERSITY
    Inventors: Haw-Ching Yang, Yu-Lung Lo, Hung-Chang Hsiao, Shyh-Hau Wang, Min-Chun Hu, Chih-Hung Huang, Fan-Tien Cheng
  • Patent number: 11383450
    Abstract: An additive manufacturing (AM) system, an AM method, and an AM feature extraction method are provided. The AM system includes an AM tool, a product metrology system, an in-situ metrology system, a virtual metrology (VM) system, a compensator, a track planner, a controller, a simulator and an augmented reality (AR) device. The simulator is used to find feasible parameter ranges, while the AR device is used to support operations and maintenance of the AM tool. The product metrology system, the in-situ metrology system and the VM system are integrated to estimate the variation of material on a powder bed of the AM tool. The compensator is used for compensating the process variation by adjusting process parameters. The product metrology system is used to measure the quality of products. The in-situ metrology system is used to collect features of melt pools on the powder bed.
    Type: Grant
    Filed: April 22, 2020
    Date of Patent: July 12, 2022
    Assignee: NATIONAL CHENG KUNG UNIVERSITY
    Inventors: Haw-Ching Yang, Yu-Lung Lo, Hung-Chang Hsiao, Shyh-Hau Wang, Min-Chun Hu, Chih-Hung Huang, Fan-Tien Cheng
  • Patent number: 11361706
    Abstract: A micro-LED display system is disclosed. The micro-LED display system includes a host, a plurality of row/column drivers and a plurality of ?ICs. The row/column drivers are coupled to the host through serial interfaces and used to provide a plurality of row clock signals and a plurality of column data signals respectively. The ?ICs are arranged as a matrix including columns of ?ICs and rows of ?ICs receiving the column data signals and the row clock signals respectively. All ?ICs in the same column of ?ICs are cascaded in order and all ?ICs in the same row of ?ICs are cascaded in order.
    Type: Grant
    Filed: January 8, 2021
    Date of Patent: June 14, 2022
    Assignee: Raydium Semiconductor Corporation
    Inventors: Kuan-Hsien Lee, Chien-Yu Chan, Yann-Hsiung Liang, Yu-Lung Lo
  • Patent number: 11300560
    Abstract: A system for sensing concentration is provided. A light source emits at least a light ray which passes through a first polarization state changing module and is directed to a biological tissue to generate a response light ray. The response light ray is received by a sensor after passing through a second polarization state changing module. A calculation circuit calculates a Muller matrix corresponding to the biological tissue according to the response light ray, and calculates a depolarization index of the biological tissue according to the Muller matrix, and calculates an optical path length according to the depolarization index, and calculates the concentration of matter of the biological tissue according to the optical path length.
    Type: Grant
    Filed: November 23, 2020
    Date of Patent: April 12, 2022
    Assignee: National Cheng Kung University
    Inventors: Yu-Lung Lo, Chieh-Chen Tsai
  • Publication number: 20220099653
    Abstract: A system for sensing concentration is provided. A light source emits at least a light ray which passes through a first polarization state changing module and is directed to a biological tissue to generate a response light ray. The response light ray is received by a sensor after passing through a second polarization state changing module. A calculation circuit calculates a Muller matrix corresponding to the biological tissue according to the response light ray, and calculates a depolarization index of the biological tissue according to the Muller matrix, and calculates an optical path length according to the depolarization index, and calculates the concentration of matter of the biological tissue according to the optical path length.
    Type: Application
    Filed: November 23, 2020
    Publication date: March 31, 2022
    Inventors: Yu-Lung LO, Chieh-Chen TSAI
  • Publication number: 20210402476
    Abstract: An additive manufacturing (AM) method is provided. The method includes performing a laser powder bed fusion (L-PBF) process on the powder layer. Then, a first surface roughness value of the powder layer after the L-PBF process is obtained to generate a first surface profile. An absorptivity and a set of re-melting process parameters data are used to perform a heat transfer simulation. A second surface profile of the powder layer after laser re-melting is obtained by using the first surface profile and a low-pass filter. Then, the set of re-melting process parameters data is adjusted iteratively to perform the heat transfer simulation until a second surface roughness value predicted from the second surface profile is smaller than or equal to a surface roughness threshold, thereby obtaining optimal values of re-melting process parameters for performing a re-melting process to reduce a surface roughness of a powder layer after the L-PBF process.
    Type: Application
    Filed: June 24, 2021
    Publication date: December 30, 2021
    Inventors: Hong-Chuong TRAN, Yu-Lung LO, Haw-Ching YANG, Fan-Tien CHENG
  • Patent number: 11110651
    Abstract: A method of performing powder bed fusion process is provided. A powder bed and a group of information of the powder bed are obtained. A powder bed simulation is performed to obtain a thickness of the powder bed and a packing density. Then, a group of parameters of a laser is obtained. A Ray Tracing simulation for the powder layer and a heat transfer simulation are performed. A first surrogate model is constructed to obtain first processing maps. The points in the first processing maps with the depths of the melt pool that are greater than a predetermined depth value and smaller than a laser beam radius are a first group of parameter values. A parameter setting operation is performed by using the first group of parameter values. A laser melting operation is performed, and a temperature distribution is measured by using an infrared thermal camera.
    Type: Grant
    Filed: September 12, 2019
    Date of Patent: September 7, 2021
    Assignee: NATIONAL CHENG KUNG UNIVERSITY
    Inventors: Yu-Lung Lo, Hong-Chuong Tran
  • Publication number: 20210217354
    Abstract: A micro-LED display system is disclosed. The micro-LED display system includes a host, a plurality of row/column drivers and a plurality of ?ICs. The row/column drivers are coupled to the host through serial interfaces and used to provide a plurality of row clock signals and a plurality of column data signals respectively. The ?ICs are arranged as a matrix including columns of ?ICs and rows of ?ICs receiving the column data signals and the row clock signals respectively. All ?ICs in the same column of ?ICs are cascaded in order and all ?ICs in the same row of ?ICs are cascaded in order.
    Type: Application
    Filed: January 8, 2021
    Publication date: July 15, 2021
    Inventors: Kuan-Hsien Lee, Chien-Yu Chan, Yann-Hsiung Liang, Yu-Lung Lo
  • Publication number: 20200247064
    Abstract: An additive manufacturing (AM) system, an AM method, and an AM feature extraction method are provided. The AM system includes an AM tool, a product metrology system, an in-situ metrology system, a virtual metrology (VM) system, a compensator, a track planner, a controller, a simulator and an augmented reality (AR) device. The simulator is used to find feasible parameter ranges, while the AR device is used to support operations and maintenance of the AM tool. The product metrology system, the in-situ metrology system and the VM system are integrated to estimate the variation of material on a powder bed of the AM tool. The compensator is used for compensating the process variation by adjusting process parameters. The product metrology system is used to measure the quality of products. The in-situ metrology system is used to collect features of melt pools on the powder bed.
    Type: Application
    Filed: April 22, 2020
    Publication date: August 6, 2020
    Inventors: Haw-Ching YANG, Yu-Lung LO, Hung-Chang HSIAO, Shyh-Hau WANG, Min-Chun HU, Chih-Hung HUANG, Fan-Tien CHENG
  • Publication number: 20200198230
    Abstract: A method of performing powder bed fusion process is provided. A powder bed and a group of information of the powder bed are obtained. A powder bed simulation is performed to obtain a thickness of the powder bed and a packing density. Then, a group of parameters of a laser is obtained. A Ray Tracing simulation for the powder layer and a heat transfer simulation are performed. A first surrogate model is constructed to obtain first processing maps. The points in the first processing maps with the depths of the melt pool that are greater than a predetermined depth value and smaller than a laser beam radius are a first group of parameter values. A parameter setting operation is performed by using the first group of parameter values. A laser melting operation is performed, and a temperature distribution is measured by using an infrared thermal camera.
    Type: Application
    Filed: September 12, 2019
    Publication date: June 25, 2020
    Inventors: Yu-Lung LO, Hong-Chuong TRAN
  • Publication number: 20200147893
    Abstract: An additive manufacturing (AM) system, an AM method, and an AM feature extraction method are provided. The AM system includes an AM tool, a product metrology system, an in-situ metrology system, a virtual metrology (VM) system, a compensator, a track planner, a controller, a simulator and an augmented reality (AR) device. The simulator is used to find feasible parameter ranges, while the AR device is used to support operations and maintenance of the AM tool. The product metrology system, the in-situ metrology system and the VM system are integrated to estimate the variation of material on a powder bed of the AM tool. The compensator is used for compensating the process variation by adjusting process parameters. The product metrology system is used to measure the quality of products. The in-situ metrology system is used to collect features of melt pools on the powder bed.
    Type: Application
    Filed: October 2, 2019
    Publication date: May 14, 2020
    Inventors: Haw-Ching YANG, Yu-Lung LO, Hung-Chang HSIAO, Shyh-Hau WANG, Min-Chun HU, Chih-Hung HUANG, Fan-Tien CHENG
  • Patent number: 10605665
    Abstract: A method for measuring a temperature of a process area is provided. A simulation computation is performed to obtain a simulation temperature. A ratio-pyrometer with two one-color modes is used to measure the temperature of the process area, and a first emissivity value and a second emissivity value are acquired. An emissivity ratio is set to a ratio of the second emissivity value to the first emissivity value, and the ratio-pyrometer in the two-color mode is used to measure the temperature of the process area.
    Type: Grant
    Filed: October 31, 2017
    Date of Patent: March 31, 2020
    Assignees: NATIONAL CHENG KUNG UNIVERSITY, National Chung-Shan Institute of Science & Technology
    Inventors: Yu-Lung Lo, Chi-Guang Ren
  • Publication number: 20190128738
    Abstract: A method for measuring a temperature of a process area is provided. A simulation computation is performed to obtain a simulation temperature. A ratio-pyrometer with two one-color modes is used to measure the temperature of the process area, and a first emissivity value and a second emissivity value are acquired. An emissivity ratio is set to a ratio of the second emissivity value to the first emissivity value, and the ratio-pyrometer in the two-color mode is used to measure the temperature of the process area.
    Type: Application
    Filed: October 31, 2017
    Publication date: May 2, 2019
    Inventors: Yu-Lung LO, Chi-Guang REN
  • Patent number: 10188332
    Abstract: A system for sensing glucose concentration is provided and includes following components. A light source generates a light beam. The system may include a polarization state generator (PSG) for changing the polarization of the light beam, and then the light beam is emitted to a biological tissue. A polarization state analyzer (PSA) receives the light beam reflected from the biological tissue, and the received light beam is used to calculate Stokes vectors. A Mueller matrix is calculated according to the Stokes vectors. In some embodiments, the system includes an optical coherence tomography (OCT) in which the light beam is sensed by a detector for calculating the Mueller matrix. An optical rotation angle and a depolarization index are calculated in accordance with the differential Mueller matrix formalism. The glucose concentration is calculated in accordance with the optical rotation angle and the depolarization index.
    Type: Grant
    Filed: January 4, 2018
    Date of Patent: January 29, 2019
    Assignee: NATIONAL CHENG KUNG UNIVERSITY
    Inventors: Yu-Lung Lo, Quoc-Hung Phan, Chia-Chi Liao
  • Publication number: 20180228415
    Abstract: A system for sensing glucose concentration is provided and includesZZ following components. A light source generates a light beam. The system may include a polarization state generator (PSG) for changing the polarization of the light beam, and then the light beam is emitted to a biological tissue. A polarization state analyzer (PSA) receives the light beam reflected from the biological tissue, and the received light beam is used to calculate Stokes vectors. A Mueller matrix is calculated according to the Stokes vectors. In some embodiments, the system includes an optical coherence tomography (OCT) in which the light beam is sensed by a detector for calculating the Mueller matrix. An optical rotation angle and a depolarization index are calculated in accordance with the differential Mueller matrix formalism. The glucose concentration is calculated in accordance with the optical rotation angle and the depolarization index.
    Type: Application
    Filed: January 4, 2018
    Publication date: August 16, 2018
    Inventors: Yu-Lung LO, Quoc-Hung PHAN, Chia-Chi LIAO